Table of Content

01 April 2022, Volume 38 Issue 2

Previous Issue    Next Issue

Editorial

Special Column on Covalent Organic Framework

Qianrong Fang, Yong Cui, Wei Wang

2022, 38(2):  1-4.  doi:10.1007/s40242-022-2000-6

Abstract ( )   PDF (204KB) ( )  

Related Articles | Metrics

Content

Chemical Research in Chinese Universities Vol.38 No.2 April 2022

2022, 38(2):  1-10. 

Abstract ( )   PDF (1956KB) ( )  

Related Articles | Metrics

Reviews

Two-dimensional Covalent Organic Frameworks: Tessellation by Synthetic Art

WANG Lu, WANG Dong

2022, 38(2):  265-274.  doi:10.1007/s40242-022-1489-z

Abstract ( )  

References | Related Articles | Metrics

Covalent organic frameworks(COFs) featuring designable nanoporous structures exhibit many fascinating properties and have attracted great attention in recent years for their intriguing application potential in sensing, catalysis, gas storage and separation, optoelectronics, etc. Rational design of twodimensional(2D) COFs through judiciously selecting chemical building blocks is critical to acquiring predetermined skeleton and pore structures. In this perspective, we review the reticular synthesis of 2D COFs with different topologies, highlighting the important role of various characterization techniques in crystal structure determination. 2D COFs with simple tessellations have been widely investigated, while the synthesis of complex tessellated COFs is still a great challenge. Some recent examples of 2D COFs with novel topological structures are also surveyed.



Covalent Organic Frameworks for Photocatalytic Organic Transformation

LI Jiali, ZHANG Zhenwei, JIA Ji, LIU Xiaoming

2022, 38(2):  275-289.  doi:10.1007/s40242-022-1434-1

Abstract ( )  

References | Related Articles | Metrics

Photocatalytic organic transformation is an efficient, energysaving and environmentally friendly strategy for organic synthesis. The key to developing a green and economical route for photocatalytic organic synthesis lies in the construction of optimal photocatalysts. Covalent organic frameworks(COFs), a kind of porous crystalline materials with characteristics of high surface area, excellent porosity, and superior thermo-chemical stability, have driven people to explore their potential as photocatalysts in photocatalytic organic transformations by virtue of their structural versatility and designability. Furthermore, the insolubility of COFs makes it possible to recycle the catalysts by simple technical means. In recent years, researchers have made great efforts to develop both the design strategies of COFs as heterogeneous photocatalysts and the reaction types of photocatalytic organic transformations. In this review, we focus on the design of COF-based photocatalytic materials and analyze the influence factors of photocatalytic performance. Moreover, we summarize the application of COFbased photocatalysts in photocatalytic organic conversion. Finally, the perspectives on new opportunities and challenges in the field are discussed.



Covalent Organic Frameworks(COFs) for Sequestration of⁹⁹TcO₄^–

DI Zhengyi, MAO Yining, YUAN Heng, ZHOU Yan, JIN Jun, LI Cheng-Peng

2022, 38(2):  290-295.  doi:10.1007/s40242-022-1447-9

Abstract ( )  

References | Related Articles | Metrics

Covalent organic frameworks(COFs), as a class of crystalline porous materials with periodic lattices and porous structures, have received extensive attention in the fields of gas storage and separation, energy storage, catalysis and optoelectronics and so on. However, COFs are still in their infancy in the field of nuclear waste treatment, especially for sequestration of long-live problematic radionuclides, such as ⁹⁹Tc. Battle of decontamination of pertechnetate(TcO₄^–), a main existence of ⁹⁹Tc under aerobic environments, is far from finished. In this review, recent progresses of COFs and some relative materials in the sequestration of pertechnetate, and perspective on surmounting the unmet issues are elucidated.



Ionic Covalent Organic Framework: What Does the Unique Ionic Site Bring to Us?

FU Yu, LI Yinhui, ZHANG Wenxiang, LUO Chen, JIANG Lingchang, MA Heping

2022, 38(2):  296-309.  doi:10.1007/s40242-022-1448-8

Abstract ( )  

References | Related Articles | Metrics

Ionic covalent organic frameworks featuring both crystallinity and charged sites have arose tremendous attention from scientific community. The adjustable textural structures, well-defined channels and abundant charged sites of ionic COFs facilitate great potential in diverse aspects, such as separation, ion conduction, sensing, catalysis and energy storage. In this review, we first introduced the design and construction of ionic covalent organic frameworks(COFs), and classified them according to the types of charged sites. We focused on the various applications of ionic COFs in diverse fields. The structure-function relationship was also explored in detail. Finally, the opportunities and challenges of ionic COFs were summarized to provide guidance for better design and application of ionic COFs.



Covalent Triazine Frameworks(CTFs) for Photocatalytic Applications

SUN Ruixue, TAN Bien

2022, 38(2):  310-324.  doi:10.1007/s40242-022-1468-4

Abstract ( )  

References | Related Articles | Metrics

Covalent triazine frameworks(CTFs) as a new type of porous organic polymers(POPs) with nitrogen-rich content, high chemical stability, visible light sensitive, metal-free and fully conjugated structure, have gained considerable attention in the last ten years owing to their great potential in extensive applications, especially for photocatalysis systems. In this review, we propose to provide current progress in the design and synthesis of CTFs, along with an emphasis on their photocatalytic applications. Firstly, a brief background including the development of photocatalytic areas is provided. Then, synthetic strategies of CTFs are described and compared. Furthermore, the evolution of CTF materials in photocatalysis fields and strategies for enhancing photocatalytic performance is presented. Finally, some perspectives and challenges on synthesizing high crystalline CTFs and designing excellent catalytic performance of CTF materials are discussed, inspiring the development of CTF materials in photocatalytic applications.



Microstructure Manipulation of Covalent Organic Frameworks (COFs)-based Membrane for Efficient Separations

MA Hanze, WANG Shaoyu, REN Yanxiong, WANG Yuhan, ZHU Ziting, HE Guangwei, JIANG Zhongyi

2022, 38(2):  325-338.  doi:10.1007/s40242-022-1474-6

Abstract ( )  

References | Related Articles | Metrics

Covalent organic framework(COF) membranes have exhibited great potential to become the next-generation membranes for efficient separations due to the diverse structures, ordered framework pores, tunable functionality and excellent stability. This review presents the microstructure manipulation strategies for separation performance enhancement of COF membranes in recent years. Based on the three mechanisms of molecular sieving, surface diffusion, and facilitated transport, the structural modulation methods to enhance the selectivity of COF membranes are analyzed in detail. Next, strategies of realizing ultrashort mass transfer pathways and ultralow mass transfer resistance for the permeability enhancement are elaborated. Furthermore, the framework stability in COFs, interlayer stability between COF nanosheets and interfacial stability between COF layer and substrate are discussed. Finally, we discuss the existing challenges and perspectives on the future development of COF membranes, targeting at identifying the most promising strategies and directions for the engineering of COF membranes.



Recent Advances of Covalent Organic Frameworks in Chemical Sensing

XU Kai, HUANG Ning

2022, 38(2):  339-349.  doi:10.1007/s40242-022-1476-4

Abstract ( )  

References | Related Articles | Metrics

With the rapid development of reticular chemistry, an increasing number of covalent organic frameworks(COFs) have been designed and synthesized over the past decades. Owing to the large surface areas, numerous active sites, and high chemical stability, recent effects gradually were made to investigate the interaction with various small molecules. Among the reported application areas, sensorics is an attractive field, where COFs have exhibited tremendous potential and acquired high- performance sensitivity and selectivity due to their structural merits. In this review, we highlighted the recent progress of COFs as sensors for the detection of various analytes, mainly depending on the analysis of change of fluorescence signals. The basic principles of physics for fluorescence-based sensors were briefly discussed for better understanding of the relationship between structures and functions of COFs. Moreover, we reviewed various classes of small molecule analytes that have been successfully detected by COFs, including explosives, gases, humidity, metal ions, pH, and biological molecules. In this work, we detailedly discussed the components of COFs, functional sites, and sensing performance in each sensing application, aiming to disclose their intrinsic connection. This review also concluded with several issues to be solved and provided the outlook for the future development direction for practical applications.



Recent Advances of Covalent Organic Frameworks for Chiral Separation

HOU Bang, LI Ziping, KANG Xing, JIANG Hong, CUI Yong

2022, 38(2):  350-355.  doi:10.1007/s40242-022-1490-6

Abstract ( )  

References | Related Articles | Metrics

Covalent organic frameworks(COFs), orderly assembled from the building blocks via covalent bonds, are a novel type of porous materials with rich functional sites and permanent porosity. At present, most of COFs are achiral networks, nevertheless, chiral COFs(CCOFs) have become a research hotspot in recent years, due to their unique chiral sites and microenvironment. As one of the most important applications of CCOFs, chiral separation has attracted huge attention for the convenient, rapid and efficient feature. In this review, recent progresses of covalent organic frameworks for chiral separation are covered. And we also present the challenges and outlooks of CCOFs in the future for this field.



Energy Storage in Covalent Organic Frameworks: From Design Principles to Device Integration

DING Huimin, MAL Arindam, WANG Cheng

2022, 38(2):  356-363.  doi:10.1007/s40242-022-1494-2

Abstract ( )  

References | Related Articles | Metrics

Covalent organic frameworks(COFs) have received profound attention in recent years owing to their tailor-made porosity, large surface area and robust stability. More specifically, 2D COFs with redox-active and π electron-rich units allow efficient charge carriers hopping and ion migration, thus offering great potentials in energy storage. Herein, we present a systematic and concise overview of the recent advances in 2D COFs related to the electrochemical energy field, including supercapacitors, fuel cells, rechargeable lithium batteries, lithium-sulfur batteries, and other metal-ion batteries. In addition, a brief outlook is proposed on the challenges and prospects of COFs as electrode materials for energy storage.



Pore Engineering for Covalent Organic Framework Membranes

YAO Jin, LU Ya, SUN Huihui, ZHAO Xin

2022, 38(2):  364-372.  doi:10.1007/s40242-022-1507-1

Abstract ( )  

References | Related Articles | Metrics

Membrane technology is of particular significance for the sustainable development of society owing to its potential capacity to tackle the energy shortage and environmental pollution. Membrane materials are the core part of membrane technology. Researchers have always been pursuing predictable structures of advanced membrane materials, which provides a possibility to fully unlock the potential of membranes. Covalent organic frameworks(COFs), with the advantage of controllable pore microenvironment, are considered to be promising candidates to achieve this design concept. The customizable function of COF membranes through pore engineering does well in the enhancement of selective permeability performance, which offers COF membranes with great application potentials in separation and transportation fields. In this context, COF-based membranes have been developed rapidly in recent years. Herein, we present a brief overview on the strategies developed for pore engineering of COF membranes in recent years, including skeleton engineering, pore surface engineering, host-guest chemistry and membrane fabrication. Moreover, the features of transmission or separation of molecules/ions based on COF membranes and corresponding applications are also introduced. In the last part, the challenges and prospects of the development of COF membranes are discussed.



Two-dimensional Covalent Organic Frameworks: Intrinsic Synergy Promoting Photocatalytic Hydrogen Evolution

LIU Shujing, GUO Jia

2022, 38(2):  373-381.  doi:10.1007/s40242-022-2007-z

Abstract ( )  

References | Related Articles | Metrics

Covalent organic frameworks(COFs) are emerging photocatalysts for hydrogen evolution in water splitting in recent years. They offer a pre-designable platform to design tailor-made structures and chemically adjustable functionality in terms of photocatalysis. In this review, we summarize the recent striking progress of COF-based photocatalysts in design and synthesis. Firstly, different approaches to functionalizing building blocks, diversifying linkages, extending π-conjugation and establishing D-A conjugation are illustrated for enhancing photocatalytic activity. Next, post-modification of backbones and pores is detailed for emphasizing the synergistic catalytic uniqueness of COFs. Besides, the strategy of preparing COF-related composites with various semiconductors is outlined for optimizing the electronic properties. Finally, we conclude with the current challenges and promising opportunities for the exploration of new COF-based photocatalysts.



Covalent Organic Frameworks with trans-Dimensionally Vinylene-linked π-Conjugated Motifs

BI Shuai, MENG Fancheng, ZHANG Zixing, WU Dongqing, ZHANG Fan

2022, 38(2):  382-395.  doi:10.1007/s40242-022-2010-4

Abstract ( )  

References | Related Articles | Metrics

Vinylene-linked covalent organic frameworks(COFs) are a class of promising porous organic materials that feature fully π-conjugated structures, high crystallinity, permanent porosity, ultrahigh chemical stability, and extraordinary optoelectronic properties. Over the past 5 years, this kind of material has been witnessed rapid development either in chemical synthesis or in potential applications. In this review, we summarize the chemistry to synthesize vinylene-linked COFs, especially the synthetic strategies involving activation of aryl methyl groups for condensation reaction. We then scrutinize the state-of-the-art development in properties and functions of this kind of COFs. Our own opinions on the further development of the vinylene-linked COFs are also presented for discussion.



Articles

Stable Thiophene-sulfur Covalent Organic Frameworks for Oxygen Reduction Reaction(ORR)

CHANG Shunkai, LI Cuiyan, LI Hui, ZHU Liangkui, FANG Qianrong

2022, 38(2):  396-401.  doi:10.1007/s40242-022-1465-7

Abstract ( )  

References | Related Articles | Metrics

Exploring novel materials deriving from earth resources to substitute for platinum(Pt) electrocatalyst to promote oxygen reduction reaction(ORR) of fuel cell cathode is very important. Herein, we have exploited two crystallographic thiophene-sulfur covalent organic frameworks(COFs), termed JUC-607 and JUC-608, as electrocatalysts that exhibited good ORR performances. These thiophene-sulfur COFs exhibited high stability, and their functional groups acting as active centers in the ORR can be precisely determined. Notably, due to a larger aperture for mass transfer and electrons transport, JUC-608 displayed a growing electrochemical performance, leading to a better ORR activity. Thus, this study will provide a new strategy for designing heteroatom-based COF materials for high-performance electrochemical catalysis.



Construction of a Three-dimensional Covalent Organic Framework via the Linker Exchange Strategy

CUI Yumeng, MIAO Zhuang, LIU Qi, JIN Fenchun, ZHAI Yufeng, ZHANG Lingyan, WANG Wenli, WANG Ke, LIU Guiyan, ZENG Yongfei

2022, 38(2):  402-408.  doi:10.1007/s40242-021-1295-z

Abstract ( )  

References | Related Articles | Metrics

Covalent organic framework(COF) is a porous crystalline material with a well-controlled structure and a wide range of potential applications. However, the construction of new COF faces huge challenges, including the design and synthesis of structural unit monomers, the choice of reaction solvent system, and the study of reaction time and temperature. So, it’s particularly important to widen the application scope of synthetic methods and further promote the development of COFs. Here, we performed structural transformations in a three-dimensional(3D) COF(COF-300), and Fourier transform infrared spectroscopy(FTIR), power X-ray diffraction analysis(PXRD) and nitrogen adsorption isotherms confirmed the chemical principles and the successful realization of these exchanges. At the same time, we found that the interpenetrating structure in 3D COF can be changed through the conversion of linkers. The structure simulation successfully proved the transformation of COF from five-fold to seven-fold interpenetration. In addition, in order to prove the versatility of this strategy, we used the same method to convert COF-300 into a high crystallinity 3D COF(TJNU-COF-302) that is also seven-fold interpenetrating and has not been reported. This simple strategy not only makes it easy to obtain a 3D COF connected with imines, which greatly promotes the development of COF, but also provides a new way to develop 3D COFs with complex interpenetrating structures.



Construction of Tetrathiafulvalene-based Covalent Organic Frameworks for Superior Iodine Capture

WANG Guangbo, XIE Kehui, ZHU Fucheng, KAN Jinglan, LI Sha, GENG Yan, DONG Yubin

2022, 38(2):  409-414.  doi:10.1007/s40242-022-1417-2

Abstract ( )  

References | Related Articles | Metrics

The effective capture of radioiodine species during nuclear fuel reprocessing and nuclear accidents is of primary importance but remains challenging for the sustainable development of nuclear energy. Herein, we report two newly designed two-dimensional(2D) and three-dimensional(3D) covalent organic frameworks by introducing tetrathiafulvalene functional groups into the building units for the simultaneous physisorption and chemisorption capture of iodine molecules. Remarkably, the obtained 3D TTF-TAPT-COF material exhibited a superior iodine vapor adsorption capacity of up to 5.02 g/g at 348 K and under ambient pressure and an adsorption kinetics of 0.515 g/(g∙h), surpassing most of other materials reported so far. The strong physiochemical interactions between iodine molecules and the frameworks of the obtained COFs were revealed by a set of experimental techniques. This study provides a feasible approach for the rational design and the construction of novel and effective COF-based adsorbents for iodine enrichment and related environmental remediation.



An Eosin Y Encapsulated Cu(I) Covalent Metal Organic Framework for Efficient Photocatalytic Sonogashira Cross-coupling Reaction

YOU Peiye, WEI Rongjia, NING Guohong, LI Dan

2022, 38(2):  415-420.  doi:10.1007/s40242-021-1444-4

Abstract ( )  

References | Related Articles | Metrics

Sonogashira cross-coupling reaction is significant for the formation of C―C bonds and the creation of new substance in organic synthesis, which is usually catalyzed using noble metal, such as palladium or non-precious metal, such as copper under harsh reaction conditions. Herein, we report the encapsulation of an organic dye(i.e., Eosin Y, EY) into a Cu(I) cyclic trinuclear unit(CTU) based covalent-metal organic framework(CMOF), namely EY@JNM-1, which demonstrates outstanding photocatalytic performance for the Sonogashira cross-coupling reaction of iodobenzene with alkynes. The EY@JNM-1 not only exhibited high catalytic activity for the alkynes(>99% conversion) and excellent selectivity for the cross-coupling product(>99%) under mild conditions, but also displayed excellent stability and recyclability.



Predicting of Covalent Organic Frameworks for Membrane-based Isobutene/1,3-Butadiene Separation: Combining Molecular Simulation and Machine Learning

CAO Xiaohao, HE Yanjing, ZHANG Zhengqing, SUN Yuxiu, HAN Qi, GUO Yandong, ZHONG Chongli

2022, 38(2):  421-427.  doi:10.1007/s40242-022-1452-z

Abstract ( )  

References | Related Articles | Metrics

Efficient separation of C4 olefins is of critical importance and a challenging task in petrochemical industry. Covalent organic frameworks(COFs) could be used as promising candidates for membrane-based isobutene/1,3-butadiene(i-C₄H₈/C₄H₆) separation. Owing to large amounts of COFs appearing, however, the rapid prediction of optimal COFs is imperative before experimental efforts. In this work, we combine molecular simulation and machine learning to study COF membranes for efficient isolation of i-C₄H₈ over C₄H₆. Using molecular simulation, four potential COF membranes, which possess both high membrane performance score (MPS) value and moderate membrane selectivity were screened out and the mechanism of membrane separation further revealed is an adsorption dominated process. Further, random forest(RF) model with high prediction accuracy(R²>0.84) was obtained and used for elucidating key factors in controlling the membrane selectivity and i-C₄H₈ permeability. Ultimately, the optimal COF features were obtained through structure-performance relationship study. Our results may trigger experimental efforts to accelerate the design of novel COFs with better i-C₄H₈/C₄H₆separation performance.



Dimeric Calix[4]resorcinarene-based Porous Organic Cages for CO₂/CH₄ Separation

YANG Miao, WANG Wenjing, SU Kongzhao, YUAN Daqiang

2022, 38(2):  428-432.  doi:10.1007/s40242-022-1454-x

Abstract ( )  

References | Related Articles | Metrics

Investigating gas separation by emerging porous organic cage(POC) solids is still on its initial stage. In this work, two novel [2+4] organic cages with distinguished structures have been prepared based on the Schiff-based condensation reaction between tetraformyl-functionalized calix[4]resorcinarene building blocks and xylylenediamine(XDA) isomers. Specifically, the use of para-position XDA affords lantern-shaped cage(CPOC-105) with a medium cavity of ca. 0.526 nm³, while the meta-position produces peanut-shaped structure(CPOC-106) with two small cavities of ca. 0.181 nm³. Both CPOC-105 and CPOC-106 exhibit high selectivity capture of CO₂ over CH₄ with calculated selectivity coefficients of 4.5 and 3.1, respectively, under ambient conditions, and are capable of separating CO₂/CH₄ mixtures by fixed-bed column breakthrough experiments.



Decorating Covalent Organic Frameworks with High-density Chelate Groups for Uranium Extraction

QIN Xudong, TANG Xiaohui, MA Yu, XU Hong, XU Qing, YANG Weiting, GU Cheng

2022, 38(2):  433-439.  doi:10.1007/s40242-022-1463-9

Abstract ( )  

References | Related Articles | Metrics

The extraction of uranium from aqueous solution is highly desirable for sustaining the increasing demand for environmental safety and nuclear fuel. Herein, we report a strategy using a two-step covalent modification for the synthesis of covalent organic frameworks(COFs) with high-density amidoxime chelate groups at periphery. The introduction of dense amidoxime groups plays a pivotal role in uranium adsorption. The resulting COF exhibits strong affinity with the distribution coefficient of 5.2×10⁴ mL/g and a high adsorption capacity of 319.9 mg/g. The strategy could be expanded to identify and remove different contaminants by introducing special functional groups.



Ultrathin 2D Covalent Organic Framework Film Fabricated via Langmuir-Blodgett Method with a “Two-in-One” Type Monomer

MENG Weijia, LI Yang, ZHAO Ziqiang, SONG Xiaoyu, LU Fanli, CHEN Long

2022, 38(2):  440-445.  doi:10.1007/s40242-022-1477-3

Abstract ( )  

References | Related Articles | Metrics

In recent years, covalent organic frameworks(COFs) are evolving as a novel kind of porous materials for catalysis and molecular separation, gas adsorption, etc. Various functional building blocks have been explored to tune the pore channels, including the pore size and structures. In this article, a new terphenyl(TP) based COF(TP-COF) was developed via a “two-in-one” strategy by using a symmetric A₂B₂monomer, i.e., 4,4''-diamino-2',5'-diformyl-1,1':4',1''-terphenyl(DADFTP). The pore size of TP-COF was only 0.99 nm by shortening the arm length of the DADFTP monomer. Freestanding, continuous and ultrathin COF films could be facilely prepared at the air-liquid interface through the modified Langmuir-Blodgett(LB) method. TP-COF films exhibited high rejection of over 90% for dyes removal.



Functionalized COFs with Quaternary Phosphonium Salt for Versatilely Catalyzing Chemical Transformations of CO₂

WANG Tianxiong, MU Zhenjie, DING Xuesong and HAN Baohang

2022, 38(2):  446-455.  doi:10.1007/s40242-022-1495-1

Abstract ( )  

References | Related Articles | Metrics

Currently, it encounters great challenges to accomplish catalyzing various kinds of carbon dioxide(CO₂) conversion reactions efficiently with single catalyst, let alone control the interplay among catalytic efficiency and selectivity evenly. Here, we prepared a functional covalent organic framework, [PTPP]_X%-TD-COF[PTPP=3-bromopropyltriphenylphosphonium; TD=1,3,5-tri(4-aminophenyl)benzene-1,4-diformylbenzene], by immobilizing the quaternary phosphonium salt onto the skeleton of COFs through a post-synthesis strategy for versatilely catalyzing reduction of CO₂ and CO₂ fixation on epoxide and aziridine facilely. With the typical features of COFs(such as porosity and ordered structure) and catalytic activity of the quaternary phosphonium salt, [PTPP]_X%-TD-COF possesses an intensely synergistic effect for catalyzing the chemical transformations of CO₂. Noteworthily, the quaternary phosphonium salt functionalized COFs catalyze the CO₂ reduction reaction with amine and phenylsilane to produce formylated and methylated products under gentle reaction conditions with high selectivity and efficiency. Furthermore, [PTPP]_X%-TD-COF shows high catalytic ability in CO₂ chemical fixation reactions.



A Two-dimensional Covalent Organic Framework for Iodine Adsorption

ZHANG Jianhui, LIU Jianchuan, LIU Yaozu, WANG Yujie, FANG Qianrong, QIU Shilun

2022, 38(2):  456-460.  doi:10.1007/s40242-022-1513-3

Abstract ( )  

References | Related Articles | Metrics

Radioactive iodine is a notorious pollutant in gas radioactive nuclear waste due to its radiation hazard, volatility, chemical toxicity, and high mobility. Therefore, developing a material with high efficiency-specific iodine capture is significant. Covalent organic framework(COF) has attracted significant attention as a new crystalline porous organic material. Due to its large specific surface and high chemical stability, it is an excellent alternative to adsorbents. Herein, we report a chemically stable two-dimensional COF(termed JUC-609) with specific adsorption of iodine. Adsorption experiments show that JUC-609 has an excellent iodine adsorption capacity as high as 5.9 g/g under 353 K and normal pressure condition, and iodine adsorption after multiple cycles is still maintained. Our study thus promotes the potential application of COFs in the field of environment-related applications.



Stepwise Fabrication of Proton-conducting Covalent Organic Frameworks for Hydrogen Fuel Cell Applications

JIA Shuping, ZHAO Peng, LIU Qi, CHEN Yao, CHENG Peng, YANG Yi, ZHANG Zhenjie

2022, 38(2):  461-467.  doi:10.1007/s40242-022-1514-2

Abstract ( )  

References | Related Articles | Metrics

Exploring new materials to manufacture proton-conducting membranes(PEMs) for fuel cells is highly significant. In this work, we fabricated two robust and highly crystalline porous covalent organic frameworks(COFs) via a stepwise synthesis strategy. The synthesized COF structures are integrated into high-density azo and amino groups, which allow to anchor acids for accelerating proton conduction. Moreover, the COFs exhibit good chemical stability and high hydrophilicity. These features make them potential platforms for proton conduction applications. Upon loaded with H₃PO₄, the COFs(H₃PO₄@COFs) deliver a high proton conductivity of 3.15×10^‒2 S/cm at 353 K under 95% relative humidity(RH). Furthermore, membrane electrode assemblies are fabricated using H₃PO₄@COF-26 as the solid electrolyte for a single fuel cell outputting a maximum power density of 18 mW/cm².



Laser-induced Synthesis of Ultrafine Gold Nanoparticles in Covalent Organic Frameworks

ZHANG Yin, MA Shengqian

2022, 38(2):  468-471.  doi:10.1007/s40242-022-2002-4

Abstract ( )  

References | Related Articles | Metrics

Metal nanoparticles in porous supports are of great importance for catalysis, separation and sensing, but their controllable preparation is still largely unmet. Herein, we describe a simple laser-induced synthesis of ultrafine gold nanoparticles in the covalent organic framework. Gold nanoparticles are well embedded, and they are about (1±0.1) nm in size. This work is universal for the preparation of well-dispersed and ultrafine metal nanoparticles in porous supports.



A Two-dimensional Dual-pore Covalent Organic Framework for Efficient Iodine Capture

WEN Zhongliang, WANG Shenglin, FU Siyao, QIAN Jiaying, YAN Qianqian, XU Huanjun, ZUO Kaiming, SU Xiaofang, ZENG Chaoyuan, GAO Yanan

2022, 38(2):  472-477.  doi:10.1007/s40242-022-2057-2

Abstract ( )  

References | Related Articles | Metrics

Effectively capturing volatile radioiodine generated during the nuclear fission process is considered to be a safe way to the utilization of nuclear power. Here we report a new two-dimensional covalent organic framework(2D COF), ETTA-PyTTA-COF, as a highly efficient iodine adsorbent, which is constructed through the condensation reaction between 4,4’,4’’,4’’’-(ethene-1,1,2,2-tetrayl)-tetrabenzaldehyde(ETTA) and 1,3,6,8-tetrakis(4-aminophenyl)pyrene(PyTTA). The ETTA-PyTTA-COF possesses a permanent 1D channel porous structure with a high Brunauer-Emmet-Teller(BET) surface area of 1519 m²/g and excellent chemical and thermal stability. It shows ultrahigh iodine adsorption capability, which can reach up to 4.6 g/g in vapor owing to its high BET surface area, large π-conjugated structure and plenty of imine groups in the skeleton of the COF as effective iodine sorption sites.



Configurational Selectivity Study of Two-dimensional Covalent Organic Frameworks Isomers Containing D_2h and C₂ Building Blocks

ZHENG Xuhan, ZHANG Lin, XIE Chenxiao, WANG Hui, LIU Hui, PAN Qingyan, ZHAO Yingjie

2022, 38(2):  639-642.  doi:10.1007/s40242-022-2001-5

Abstract ( )  

References | Related Articles | Metrics

The isomerization of covalent organic frameworks(COFs) materials is still a mysterious and attractive topic. Diversified monomer structures are still urgently needed to explore the in-depth mechanism of isomerization in these special COFs. This work provides a new D_2h monomer for the construction of [D_2h+C₂] 2D COFs isomers. A new D_2h monomer adopted here was proven to tend to form a single pore framework structure.



Highlight

A New Chemical Trick to Prevent House from Collapsing by Bacterial Pathogens

QIU Jiazhang, LUO Zhao-Qing

2022, 38(2):  478-480.  doi:10.1007/s40242-022-2028-7

Abstract ( )  

References | Related Articles | Metrics

Metazoans often induce cell death as an ultimate strategy to prevent disastrous damage to the body under circumstances when insults, such as infection are impossible to clear. Inflammatory cell death or pyroptosis not only eliminates the replicative niche for the pathogen but also stimulates effective immune protection. A recent study by Shao, Liu and colleagues found that the Shigella flexneri effector OspC3 inactivates an inflammasome by a novel posttranslational modification termed ADP-riboxanation. This finding has greatly expanded the chemical tool box of pathogens in their manipulation of host function, which may be used to probe unrecognized signaling mechanisms.



Review

Magnetic-Optical Imaging for Monitoring Chemodynamic Therapy

WANG Youjuan, YE Zhifei, SONG Guosheng, LIU Zhuang

2022, 38(2):  481-492.  doi:10.1007/s40242-021-1315-z

Abstract ( )  

References | Related Articles | Metrics

Chemodynamic therapy kills cancer cells with reactive oxygen species generated by endogenous triggers in the tumor microenvironment. Although chemodynamic therapy is blossoming in recent years, their therapy process still faces a series of hampers. The unknown catalytic activity of chemodynamic therapy reagents may lead to unpredictable therapy effects, so it is necessary to reveal the therapeutic mechanism of chemodynamic therapy and develop self-monitoring probes. In this mini-review, we summarize and illustrate the most recent progress of chemodynamic therapy, focusing on the applications of magnetic imaging and optical imaging probe for monitoring cancer chemodynamic therapy. Furthermore, we also discuss the potential challenges and the further directions of this field.



Letters

A Neglected Issue in Testing Particles in the Solution

ZHANG Xiaojin, DAI Yu, XIA Fan

2022, 38(2):  493-496.  doi:10.1007/s40242-021-1243-y

Abstract ( )  

References | Related Articles | Metrics



Observation of a 3-in-1 Russian-doll-like Complex in Solution

JIANG Jian

2022, 38(2):  497-499.  doi:10.1007/s40242-021-1146-y

Abstract ( )  

References | Related Articles | Metrics



Visualization of Bulk Polymerization by Fluorescent Probe with Aggregation-induced Emission Characteristics

NIU Junfeng, SUN Haiya, XIA Housheng, ZHU Yinbang, CHEN Jialing, ZHU Chengye, BAI Wei

2022, 38(2):  500-504.  doi:10.1007/s40242-021-1216-1

Abstract ( )  

References | Related Articles | Metrics



Catalyst-free Photochemical Bromination of Unprotected Aromatic Amino Acid Derivatives by Using a Rotating Ultraviolet Photoreactor

ZHANG Tingting, LUO Pan, LAI Can, LIU Zheyi, JIN Yan, WANG Fangjun

2022, 38(2):  505-509.  doi:10.1007/s40242-021-1413-y

Abstract ( )  

References | Related Articles | Metrics



Articles

Influence of SAM Quality on the Organic Semiconductor Thin Film Gas Sensors

ZHU Lunan, WANG Zi, LU Jie, ZHOU Xu, ZENG Zhoufang, HUANG Lizhen, CHI Lifeng

2022, 38(2):  510-515.  doi:10.1007/s40242-021-1167-6

Abstract ( )  

References | Related Articles | Metrics

Gas sensors based on organic semiconductors receive tremendous attentions owing to their advantages on high selectivity and room temperature operation. However, until now, most organic semiconductor based sensors still suffered from problems, such as low sensitivity, slow response/recovery speed and poor stability. In addition, a clear correlation between the sensing performance and the film property is still absent. Herein, we report the investigation on sensing performance of a series of organic films with various morphologies. By simply adjusting the quality of self-assembled monolayer(SAM) on the silicon wafer surface, we obtain organic semiconductor 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene) films with varied morphologies and different charge transport abilities. The film with a small grain size and a continuous morphology presents the highest sensing performance to NO₂, with a sensitivity up to 730%/ppm(ppm=parts per million, vo-lume ratio). We thus reveal that the high sensitivity of the organic film is evident related with the charge transport ability and initial conductivity of the films, as well as the morphologies of both modification layer and the active films.



Thermal- and Light-driven Metathesis Reactions Between Different Diselenides

KANG Xiaoying, YUAN Yuan, XU Huaping, CHEN Yulan

2022, 38(2):  516-521.  doi:10.1007/s40242-021-1149-8

Abstract ( )  

References | Related Articles | Metrics

Thermal- and light-driven diselenide metathesis reactions with different types of diselenides are investigated systematically. Their exchange reaction rates and equilibrium conversions are compared in the aspects of the different diselenide structures, activation conditions and solvents. As a result, the metathesis reactions between diselenide small molecules are demonstrated with high dynamic and sensitive features, which can be broadly tuned by varying the electron affinity and aromaticity of the diselenide substituents and external conditions(e.g., solvent, stimulus mode). The current work thus will not only advance our understanding on diselenide metathesis chemistry, but also promote concrete and impactful studies in selenium-containing materials.



Nanocomposites Facilitate the Removal of Aβ Fibrils for Neuroprotection

CHAI Jingshan, LI Qiushi, ZHAO Yu, LIU Yang

2022, 38(2):  522-528.  doi:10.1007/s40242-021-1372-3

Abstract ( )  

References | Related Articles | Metrics

Accumulation of β-amyloid(Aβ) fibrils in the brain is one of the main culprits in Alzheimer’s disease(AD) progression, which initiates the neuronal damage and subsequent neurodegeneration. Various anti-Aβ agents have shown the potentials to dissociate Aβ fibrils. However, these approaches can’t facilitate the removal of Aβ fibrils, resulting in a disappointing therapeutic effect. Herein, we demonstrate an integrated polymer nanocomposite(NP-GLVFF-IgG) that can dissociate Aβ fibrils into fragments and activate microglia to remove the fragments via Fc receptors-mediated phagocytosis. NP-GLVFF-IgG is constructed by an albumin/polymer hybrid nanoparticle with Gly-Leu-Val-Phe-Phe (GLVFF) peptides and Immunoglobulin G(IgG) molecules on the surface. In this design, NP-GLVFF-IgG achieves to dissociate the Aβ fibrils by the strong hydrogen-bonding interactions between Aβ fibrils and GLVFF peptides. Then, NP-GLVFF-IgG activates the microglial phagocytosis, thereby achieving an enhanced phagocytic removal of Aβ fibrils for neuroprotection. Moreover, NP-GLVFF-IgG achieves to trigger the effective removal of Aβ fibrils even under inflammatory condition that usually suppressed phagocytosis. Therefore, NP-GLVFF-IgG has great potential as a novel therapeutic platform for effective AD therapy.



Palladium Nanoparticles/Graphdiyne Oxide Nanocomposite with Excellent Peroxidase-like Activity and Its Application for Glutathione Detection

LAN Weifei, HU Ruifeng, HUANG Danrong, DONG Xu, SHEN Gangyi, CHANG Shan, DAI Dongsheng

2022, 38(2):  529-534.  doi:10.1007/s40242-021-1038-1

Abstract ( )  

References | Related Articles | Metrics

In this study, palladium nanoparticles loaded graphdiyne oxide (Pd/GDYO) nanocomposite were fabricated by in-situ reduction of palladium chloride in the dispersion of GDYO, and characte-rized by Raman spectra, transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The synthesized Pd/GDYO was first found to have catalytic activities similar to those of the peroxidase enzyme, which can catalyze the oxidation of peroxidase substrate 3,3',5,5'-tetramethylbenzidine(TMB) in the presence of hydrogen peroxide(H₂O₂). Steady-state kinetic studies showed that the catalytic reaction of Pd/GDYO follows a ping-pong mechanism, and Pd/GDYO has a stronger activity to TMB with a Michaelis constant(K_m) value of 5.32×10^-4 mmol/L. Based on the shielding effect of glutathione(GSH) on the Pd/GDYO-H₂O₂-TMB reaction system, a colorimetric detection method for GSH was deve-loped with a wide linear range from 0.1 μmol/L to 40 μmol/L and a limit of detection of 0.1 μmol/L. The method was successfully applied for fast and accurate detection of GSH in injection powder drugs. It was expected that this peroxidase-like Pd/GDYO nano- composite would have wide applications in the fields of biomedicine and environmental chemistry.



Molecular Modification of Benzophenone Derivatives for Lower Bioenrichment and Toxicity Through the Pharmacophore Model

XIAO Jiapeng, ZHANG Wenhui, ZHANG Shujing, LI Yu

2022, 38(2):  535-545.  doi:10.1007/s40242-021-1044-3

Abstract ( )  

References | Related Articles | Metrics

In this study, we used the improved extreme-difference normalization method to calculate the comprehensive evaluation values of bioenrichment and toxicity of benzophenone UV light absor-bers(BPs). Based on this parameter, a 3D-QSAR(QSAR=quantitative structure activity relationship) pharmacophore model was constructed using Discovery Studio software and applied to the mole-cular modification of BPs. With three commonly used ingredients in sunscreen 2-hydroxy-4-methoxybenzophenone(BP-3), 2,2'-dihydroxy-4,4'-dimethoxybenzophenone(BP-6) and 2,2'-dihydroxy-4-methoxybenzophenone(BP-8) as target molecules, we performed BPs substitution reaction based on the binding positions of characteristic elements of the pharmacophore model and designed BP derivatives with reduced bioenrichment and toxicity. Stability and function evaluation showed that while the stability of 6 BP derivatives was enhanced, the light absorption capacity was also significantly enhanced(from 9.16% to 43.16%). Molecular dynamics simulation results showed that the binding ability of BP-609 molecule with serum albumin was reduced by 16.37% compared with BP-6, and the binding with collagen could not occur spontaneously, which could be used as an explanation for the simultaneous reduction of its bioenrichment and toxicity. Besides, through the simulation of human metabolism, it was found that the liver metabolites of BP-609 were less toxic, which reduced the potential risk of human metabolism. It proved that the molecular modification scheme of BPs was environment-friendly.



Improved Method for the Total Synthesis of Azaperone and Investigation of Its Electrochemical Behavior in Aqueous Solution

Mohammad Javad TAGHIZADEH, Maryam Saleh MOHAMMADNIA, Masoumeh GHALKHANI, Esmail SOHOULI

2022, 38(2):  546-551.  doi:10.1007/s40242-021-1061-2

Abstract ( )  

References | Related Articles | Metrics

Azaperone, with anti-anxiety and anti-aggressive activities used in veterinary medicine, is a member of the butyrophenone class. It is ordinarily utilized for a wide range of indications, such as sedation, obstetrics, and anesthesia. In this research, an improved synthetic route is presented for azaperone using a phase-transfer catalyst(PTC). In general, it was synthesized as a dopamine antagonist in four steps. The bis(2-chloroethyl) amine intermediate is easily obtained after the conversion of the alcohol groups into the chloride leaving group using thionyl chloride(95% yields). The alkylation of commercially available 2-amino pyridine in the presence of PTC was then carried out, giving 1-(pyridin-2-yl) piperazine with 75% yield. 1-(Pyridin-2-yl) piperazine was finally alkylated using 4-chloro-1-(4-fluorophenyl) butan-1-one to achieve azaperone with 60% yield. The butyrophenone intermediate was obtained via the Friedel-Crafts reaction of fluorobenzene with 4-chlorobutyryl chloride in the presence of AlCl₃. High efficiency, gentle reaction conditions, and fast and simple procedure are the advantages of this method. Also, the electrochemical oxidation behaviour of azaperone was investigated using cyclic and differential pulse voltammetry techniques. Cyclic voltammetric studies indicated an irreversible process for azaperone electro-oxidation with a peak potential of 0.78 V in a phosphate buffer solution(pH=7.0) vs. Ag/AgCl(saturated KCl) electrode. The value of the peak current vs. the azaperone concentration was enhanced linearly in the range of 10―70 μmol/L, and the detection limit was found to be 3.33 μmol/L.



Multiwalled Carbon Nanotubes Modified with Silylated-salicylaldimine Co(II) and Pd(II) Complexes as Precatalysts in Ethylene Oligomerization

XUE Jingqi, LI Feng, ZHAI Xue, LI Dan, GUO Lijun, LI Cuiqin

2022, 38(2):  552-561.  doi:10.1007/s40242-021-1067-9

Abstract ( )  

References | Related Articles | Metrics

MWCNTs-Co(II) and Pd(II) were prepared through grafting silylated-salicylaldimine Pd(II) and Co(II) on multiwalled carbon nanotubes(MWCNTs) for ethylene oligomerization. The structures of the two MWCNTs-supported catalysts were characterized by means of scanning electron microscopy(SEM), X-ray diffraction(XRD), Fourier transform infrared(FTIR) spectroscopy, thermogravimetric analyses(TGA) and nitrogen adsorption and desorption. And the influence of the supported pattern on the catalytic properties for ethylene oligomerization was investigated. The results revealed that the silylated-salicylaldimine complexes were grafted on the inner and outer surfaces of the carbon nanotubes and the pore size and BET surface area of MWCNTs decreased. Compared with the homogeneous catalysts, the two MWCNTs-supported catalysts had higher selectivity for hexene and 1-hexene in the presence of diethylaluminum chloride(DEAC) with a small molecule size due to confinement effect. MWCNTs-Pd exhi-bited higher activity and higher selectivity for C₈⁺ olefin compared to MWCNTs-Co due to electronic factors. The catalytic activities of MWCNTs-Pd and MWCNTs-Co decreased from 24.18×10⁵g·(mol Pd·h)^–1 and 20.57×10⁵g·(mol Co·h)^–1 to 19.79×10⁵g·(mol Pd·h)^–1 and 13.14×10⁵g·(mol Co·h)^–1 after the third recycle reaction, respectively.



Cell Membrane-camouflaged Multi-functional Dendritic Large Pore Mesoporous Silica Nanoparticles for Combined Photothermal Therapy and Radiotherapy of Cancer

WU Liting, XIN Yujia, GUO Zhaoyang, GAO Wei, ZHU Yanpeng, br, WANG Yinsong, RAN Ruixue, YANG Xiaoying

2022, 38(2):  562-571.  doi:10.1007/s40242-021-1068-8

Abstract ( )  

References | Related Articles | Metrics

Combining photothermal therapy and radiotherapy(PTT-RT) with reducing tumor hypoxia acts as an important antitumor modality. However, it is a great challenge to realize photothermal therapy, radiotherapy and exogenous oxygen supply in one nanosystem. To realize a combination of the three functions, we fabricated a red blood cell membrane(RBCm)-camouflaged, red blood cell content(RBCc) and the copper sulfide(CuS) co-loaded dendritic large pore mesoporous silica nanoparticle(DLMSN/CuS/RBCc/ RBCm). The cell membrane coating endowed the nanoparticles with good stability in the physiological environment, and CuS allowed the nanoparticle exhibiting good photothermal and radiosensitization properties. RBCc loaded nanoparticle DLMSN/CuS/RBCc enhanced superior anti-tumor effect than DLMSN/CuS during combined PTT-RT therapy because the introduction of RBCc increased the exogenous oxygen supply. The in vitro study further demonstrated that the combination of photothermal therapy and radiotherapy induced superior antitumor efficacy than single therapy. Our work thus presents a unique multifunctional nanoscale platform favorable for combined PTT and RT.



Conformation Changes of Enkephalin in Coordination with Pb²⁺ Investigated by Gas Phase Hydrogen/Deuterium Exchange Mass Spectrometry Combined with Theoretical Calculations

HAN Jiaru, WU Fangling, YANG Shutong, WU Xiaonan, TANG Keqi, LI Zhenhua, DING Chuan-Fan

2022, 38(2):  572-578.  doi:10.1007/s40242-021-1069-7

Abstract ( )  

References | Related Articles | Metrics

In this study, the effects of lead ions(Pb²⁺) on the conformations of leucine encephalin(LE) and methionine encephalin(ME) in gas phase were studied using hydrogen/deuterium exchange mass spectrometry(HDX-MS) and quantum chemistry theoretical calculations at the molecular level. The HDX-MS result revealed that the complexes with the monovalent compounds [LE+Pb–H]⁺ and [ME+Pb–H]⁺had a 1:1 stoichiometric ratio, and different HDX reactivates were observed in a follow of [ME+H]⁺>[LE+H]⁺>[LE+Pb–H]⁺> [ME+Pb–H]⁺. Combining the collision-induced dissociation energies of the complexes and their HDX results, it was found that the more stable the complex, the harder it was for HDX. In addition, the favo-rable conformations of the complexes were obtained by theoretical calculations, revealing that the similar coordination type with diffe-rent bond lengths was obtained. Then, the proton affinity(PA) values of the optimized complexes were calculated to interpret the HDX observations, indicating that the higher the PA values, the more difficult it was for HDX. Overall, the experiments and theoretical calculations revealed that Pb²⁺ could induce conformational changes of LE and ME, and generate ME into a more rigid conformation than LE. The results will prompt further fundamental investigations on the conformational properties of LE/ME in coordination with Pb²⁺.



Theoretical Studies on the Electronic Structure of Nano-graphenes for Applications in Nonlinear Optics

CHEN Kaichun, ZHENG Xuelian, YANG Cuicui, TIAN Wei Quan, LI Weiqi, YANG Ling

2022, 38(2):  579-587.  doi:10.1007/s40242-021-1090-x

Abstract ( )  

References | Related Articles | Metrics

In this work, azulene is introduced into nano-graphene with coronene center to enhance the second-order nonlinear optical (NLO) properties. The sum-over-states(SOS) model based calculations demonstrate that dipolar contributions are larger than octupolar contributions to the static first hyperpolarizability(〈β₀〉) in most nano-graphenes except those with high symmetry(e.g., a C_2v nano-graphene has octupolar contributions Φ^J=3 up to 59.0% of the 〈β₀〉). Nano-graphenes containing two parallel orientating azulenes (i.e., Out-P and Out-P_s) have large dipole moments, while their ground state is triplet. Introducing B/N/BN atoms into the positions with a high spin density transfers the ground state of Out-P and Out-P_s to closed-shell singlet, and the Out-P_s-2N has a large 〈β₀〉 of 1621.67×10⁻³⁰ esu. Further addition of an electron donor(NH₂) at the pentagon end enhances the 〈β₀〉 to 1906.22×10⁻³⁰ esu. The two-dimensional second-order NLO spectra predicted by using the SOS model find strong sum frequency generations and difference frequency generations, especially in the near-infrared and visible regions. The strategies to stabilize the electronic structure and improve the NLO properties of azulene-defect carbon nanomaterials are proposed, and those strategies to engineer nano-graphenes to be semiconducting while maintaining the π-framework are exten-dable to other similar systems.



Highly Stable CsPbBr₃ Nanocrystal Phosphors by Surface Passivation and Encapsulation

SHANG Zheliang, XUE Weinan, WANG Wei, LI Yan

2022, 38(2):  588-595.  doi:10.1007/s40242-021-1153-z

Abstract ( )  

References | Related Articles | Metrics

The colloidal all-inorganic CsPbX₃(X=I, Br, Cl) perovskite nanocrystals(NCs) with unique optical properties have attracted considerable attention in the field of semiconductor nanocrystals, but their application is hindered by stability issues caused by surface defects and environmental factors. Usually with inert layer encapsulation, the stability of CsPbX₃ NCs can be significantly enhanced. However, due to the loss of highly dynamic oleic acid/oleylamine ligands, it is usually accompanied by a decrease in the photoluminescence quantum yield(PLQY). Herein, we report a facile method for preparing CsPbBr₃ NCs based green phosphors with high stability and bright emission. With modification of colloidal CsPbBr₃ NCs by di-dodecyldimethylammonium bromide and sequent encapsulation in the as-synthesized mesoporous MOF-5, the green emitting phosphors with enhanced stability and a PLQY of 77% were obtained. The phosphors exhibit enhanced resistance against ambient oxygen, UV light, heat treatment and water. These excellent properties show the potential value of our prepared NCs as stable phosphors in light-emitting devices.



Optimization of Electrical Conductivity of SA-graphene Nanocomposites Using Response Surface Methodology

Hakan, AHAL, Gülben TORĞUT, Erdal CANPOLAT

2022, 38(2):  596-602.  doi:10.1007/s40242-021-1154-y

Abstract ( )  

References | Related Articles | Metrics

Synthesis and characterization of 4-{(E)-[(5-bromo-2-hydroxyphenyl)methylidene]amino}-N-carbamimidoylbenzene-1-sulfonamide(SA) and its composites with graphene(SA-GF) were performed. Compound SA and SA-GF were characterized by FTIR and ¹H NMR. The GF dispersion in the composites was analyzed by means of scanning electron microscopy(SEM) for morphology. Thermal properties of SA and nanocomposites were investigated using differential thermal analysis(DTA) and thermogravimetric analysis(TGA). The optimum electrical conductivity of the new sulfonamide-based Schiff base was determined to be 1.78×10^–5 S/cm at a frequency of 9923 Hz, an applied voltage of –19 V, a mass fraction of 9.38% for graphene loading using a central composite design in the response surface methodology. The significance of the selected parameters(frequency, voltage and GF amount) in the model was determined by the analysis of variance(ANOVA). The results showed that frequency and graphene loading represent important model terms and have considerable effects on the conductivity of SA.



N-Doped Carbon Nanofibers Encapsulating CoO@Co₉S₈ Nanoparticles: Preparation from S-Rich Co₃₂ Coordination Cluster Precursors by Electrospinning and Application for Superior Li-ion Storage

YANG Siran, AI Feixue, LI Ziping, ZHAO Guiyan, BI Yanfeng

2022, 38(2):  603-608.  doi:10.1007/s40242-021-1157-8

Abstract ( )  

References | Related Articles | Metrics

Thiacalixarene-supported Co₃₂nanoclusters encapsulated in polyacrylonitrile nanofibers(Co₃₂@PAN-NFs) by electrospinning have been utilized as precursors to fabricate N-doped CoO@Co₉S₈ carbon nanofibers(CoO@Co₉S₈@CNFs) for superior Li-ion storage. The S-rich Co₃₂ clusters capped by organic sheets afforded the well dispersed cobalt oxide/sulfide nanoparticles embedded in carbon nanofiber composites by direct calcination. The N-doped CoO@Co₉S₈@CNFs nanocomposites have been utilized as anode materials for lithium ion battery with the reversible capabilities being of 1051.8, 967.6, 894.7, 782.7, 669.5 and 525.4 mA·h/g at 0.1, 0.2, 0.5, 1, 2 and 3 A/g, respectively. The CoO@Co₉S₈@CNFs also showed a relatively high stable capacity of 551.7 mA·h/g at the current density of 1 A/g after 200 cycles of rate experiments. The as-obtained N-doped CoO@Co₉S₈@CNFs nanocomposites exhibited superior reversible capacity, rate performance, Coulomb efficiency(74.5% vs. 63.9%) and cyclic stability comparing with the CoO@Co₉S₈@C derived from simple annealing of Co₃₂ templates.



A Long-wavelength Emissive Phenothiazine Derived Fluorescent Probe for Detecting HOCl Upregulation in 5-FU Stimulated Living Cells

WANG Bingya, GUO Xiaomei, LIU Zuodong, WU Yongquan, HOU Ji-Ting

2022, 38(2):  609-615.  doi:10.1007/s40242-021-1173-8

Abstract ( )  

References | Related Articles | Metrics

The endogenous hypochlorous acid(HOCl) has been evidenced in a variety of cellular courses. However, the role of HOCl in most pathophysiological processes still keeps unclear because of the limited detecting tools. In this work, we presented the pre- paration of a phenothiazine-derived fluorescent probe ClO-1 for HOCl detection with a cyanopyridinium moiety to improve its water solubility and lengthen its emission wavelength. The HOCl-promoted oxidation of sulfur atom in the probe resulted in a 460-fold emission intensity enhancement at 635 nm with high selectivity and sensitivity(detection limit: 1.12 nmol/L). The rapid response(5 s) also endowed the probe with real-time detection ability. Successfully, ClO-1 was devoted to the bioimaging of endogenous HOCl in inflamed RAW 264.7 cells and 5-fluorouracil-treated MCF-7 cells.



Study on the Mechanism of Asphaltenes Reducing Oil-Water Interfacial Tension

WANG Yuwen, CHENG Tiexin, ZHOU Guangdong

2022, 38(2):  616-621.  doi:10.1007/s40242-021-1178-3

Abstract ( )  

References | Related Articles | Metrics

As high polar components of crude oil, asphaltenes play a significant role in reducing oil-water interfacial tension(IFT). In this paper, the effects of asphaltenes on reducing IFT in the presence of surfactant were compared, and the mechanism of asphaltenes reducing the IFT was studied by the dynamic interfacial tension(DIFT) equation. Whether asphaltenes were added to the oil or 2,5-dimethyl-4-(4-dodecyl) benzene sodium sulfonate(p-S14-4) was added to the water phase, either of all results in the IFT reducing and the IFT is related to the coverage and the mass of asphaltenes adsorption at the interface. In the presence of asphaltenes, the adsorption of the active substances to the interface is not entirely dependent on diffusion, and the process can be divided into three regions. Region I: the IFT rapidly reducing, this process is controlled by diffusion of surfactant; Region II: the IFT reducing slowly, resulted from the lower diffusion rate that is limited due to the aggregates formed by the interaction of asphaltene-asphaltene; Region III: the interaction of asphaltene-asphaltene is broken by the interaction of surfactant-asphaltene. The asphaltene aggregates are reduced and adsorbed rapidly at the interface. Furthermore, the results reveal that the asphaltenes concentration affects the coverage rate and adsorption at the interface.



Theoretical Study on the Structures, Spectral Properties, and Drugability of Xenicane-type Diterpenoids from Dictyota dichotoma

HUANG Luoyi, SUN Xiang, CHEN Mengyi, YAN Pengcheng, WANG Chaojie

2022, 38(2):  622-631.  doi:10.1007/s40242-021-1296-y

Abstract ( )  

References | Related Articles | Metrics

There are few reports on the relationship between the biological activity and structure of secondary metabolites from Dictyota dichotoma. In this work, the geometric and electronic structures, infrared spectra, ultraviolet spectra, ¹³C and ¹H NMR spectra of 16 xenicane-type diterpenoids extracted from Dictyota dichotoma were studied by the density functional theory ωB97XD/6-311+G(2d,p) method. The analysis of the reactivity indices was carried out via the conceptual density functional theory. Furthermore, a pharmacodynamic evaluation was performed using ADME/Tox. The geometric structure analysis found that all 16 diterpenoids had the same unsaturated, branched chains and could be divided into two categories according to the ring size, including nine-membered and eight-membered rings. A hydroxyl group on the lactone ring reduced the stability of the compound. In contrast, a hydroxyl group on the parent ring had little effect on the compound's stability. The electrostatic potential results preliminarily predicted active sites for nucleophilic/electrophilic reactions. The fitting results of infrared and nuclear magnetic resonance(NMR) data showed that the theoretical values obtained by this method were consistent with the experimental values. The UV-visible absorption spectra showed that the solvent effects caused different redshifts of the absorption peaks. The absorption strength was enhanced. The sixteen diterpenoids displayed a strong absorption peak in the range of 180―200 nm, but the compound containing a carbonyl group presents a weaker absorption peak in the field of 200―240 nm. Compounds 9―11, 14, and 15 have better stability and reactivity with lower chemical potentials and higher electronegativity, electrophilic index, and hardness values. The local reactivity descriptors further identified nucleophilic/electrophilic reaction sites for the sixteen compounds. Finally, the pharmacodynamic evaluation results predicted that compounds 2, 4, 8, 11, and 14―16 have optimal drugability. The theoretical results of this work may provide a rich data information for the other experimental study on the cembrane diterpenoids in medicine.



Comprehensive Analysis of Differential Gene Expression Profile via RNA Sequencing in the Human Ovarian Cancer SKOV3 Cells Treated with Simvastatin

LIU Qianyu, DU Zhenwu, ZHU He, ZHAO Tianyu, PAN Ying

2022, 38(2):  632-638.  doi:10.1007/s40242-022-1325-5

Abstract ( )  

References | Related Articles | Metrics

The experimental studies have demonstrated that some statins have an anticancer effect against ovarian cancer in vitro and in vivo, however, the potential molecular mechanism is still unclear. In the present study, high throughput RNA sequencing(RNA-seq) technology was applied to exploring the mRNA changes treated with Simvastatin in the human ovarian cancer SKOV3 cell line. The result of CCK-8 assay shows that Simvastatin inhibits significantly SKOV3 cell viability in a concentration-dependent manner, and cell cycle according to the flow cytometry analysis result shows cell cycle arrest of G1 phase is induced in SKOV3 cells with 10 μg/mL simvastatin added for 24 h. The differential expression genes(DEGs) analysis of RNA-seq data shows that there are a total of 372 DEGs found in the Simvastatin group, of which 150 mRNAs are up-regulated and 222 mRNAs are down-regulated(fold change>2.0, q value < 0.05). Real time reverse transcription-polymerase chain reaction(qRT-PCR) experiment has validated that the expression of KLF2, RHOB and CIDEB is up-regulated while that of DKK1, AMOTL2 and ANKRD1 is down-regulated. The DEGs are enriched in thirteen significant KEGG pathways including cell cycle, DNA replication, apoptosis, etc. This study provides supported useful information about transcriptome profiles of SKOV3 cell treated with simvastatin, and offers an application basis for the further researches on the mechanism of Simvastatin in the treatment of ovarian cancer.