Table of Content

01 April 2021, Volume 37 Issue 2

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Editorial

Themed Issue on Advanced Battery Material Chemistry

ZHANG Xinbo, ZHANG Qiang

2021, 37(2):  1-2.  doi:10.1007/s40242-021-2000-y

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Contents

Chemical Research in Chinese Universities Vol.37 No.2 December 2021

2021, 37(2):  1-4. 

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Reviews

Recent Progress and Perspectives of Sodium Metal Anodes for Rechargeable Batteries

FANG Hengyi, GAO Suning, ZHU Zhuo, REN Meng, WU Quan, LI Haixia, LI Fujun

2021, 37(2):  189-199.  doi:10.1007/s40242-021-0449-3

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Sodium metal anodes have attracted significant attention due to their high specific capacity, low redox potential and abundant resources. However, the dendrites and unstable solid electrolyte interphase(SEI) of sodium anodes restrict the development of sodium metal batteries. This review includes the recent progress on the Na anode protection in sodium metal batteries. The strategies are summarized as modified three-dimensional current collectors, artificial solid electrolyte interphases, and electrolyte modifications. Conclusions and perspectives are envisaged for the further understanding and development of Na metal anodes.



Recent Progress on Modification Strategies of Alloy-based Anode Materials for Alkali-ion Batteries

WU Ying, YAO Yu, WANG Lifeng, YU Yan

2021, 37(2):  200-209.  doi:10.1007/s40242-021-0001-5

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Alkali-ion batteries, including lithium-ion batteries(LIBs), sodium-ion batteries(NIBs) and potassium-ion batteries (KIBs), with alloy-based anodes exhibit huge potential in high energy density due to the natural abundance, high theoretical capacity as well as suitable operating voltages. However, the practical application is severely hindered by the huge volume variation based on the alloying mechanism and inferior conductivity, especially for red phosphorus(P) and silicon(Si) anodes, which induces poor rate capability and fast capacity decay. Herein, we will briefly review fundamental advantages and challenges of alloy-based anode materials. Then, effective modification strategies of alloy-based anode materials for boosting the performance would be emphasized and discussed. Finally, we will share our perspectives and some opportunities to obtain high-performance alloy-based anode materials for further application.



Challenges and Development of Composite Solid Electrolytes for All-solid-state Lithium Batteries

LIU Li, ZHANG Dechao, XU Xijun, LIU Zhengbo, LIU Jun

2021, 37(2):  210-231.  doi:10.1007/s40242-021-0007-z

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All-solid-state lithium batteries are considered to be a new battery system with great development potential and application prospects due to the advantages of high energy density and high security. As a key component of all-solid-state lithium batteries, the development of solid-state electrolytes has received extensive attention in recent years, but most solid electrolytes still exhibit problems, such as low ion conductivity and poor interface compatibility. The design of composite solid-state electrolyte materials with both excellent electrochemical and mechanical properties is an effective way to develop all-solid-state lithium batteries. This review introduces different types of pure component solid electrolytes and analyzes their respective advantages and characteristics firstly. Furthermore, the research progress of composite electrolytes in preparation method, ionic conduction, suppression of lithium dendrites, and the improvement of electrochemical performances are reviewed from the perspective of composite electrolyte structure design, which is to meet different performance requirements. And the future development direction and trend of composite electrolytes are prospected.



Strategies with Functional Materials in Tackling Instability Challenges of Non-aqueous Lithium-Oxygen Batteries

WANG Huanfeng, LI Jingjing, LI Fei, GUAN Dehui, WANG Xiaoxue, SU Wenhua, XU Jijing

2021, 37(2):  232-245.  doi:10.1007/s40242-021-0026-9

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The instabilities of the battery including cathode corrosion/passivation, shuttling effect of the redox mediators, Li anode corrosion, and electrolyte decomposition are major barriers toward the practical implementation of lithium-oxygen(Li-O₂) batteries. Functional materials offer great potential in high performance Li-O₂ batteries owing to their functional tailorability of chemical modification for alleviating side reactions and improving catalysis activity, well-defined properties for discharge products storage, and fast mass and electron transfer paths. In this review, instability problems of non-aqueous Li-O₂ batteries and recent stu-dies related to the functional materials in tackling the instability issues from rational cathode construction, inhibition of redox mediators(RMs) shuttling, anode protection and novel electrolyte design are illustrated. Future research directions to overcome the critical issues are also proposed for this promising battery technology. The instability issues and the related strategies with functional materials based on the comprehensive consideration of all battery components proposed in this review provide the systematic, deep understanding and rational design of functional materials for Li-O₂ batte-ries, which is beneficial to achieving the practical Li-O₂ batteries.



Combination of Organic and Inorganic Electrolytes for Composite Membranes Toward Applicable Solid Lithium Batteries

MU Shuang, BI Zhijie, GAO Shenghan, GUO Xiangxin

2021, 37(2):  246-253.  doi:10.1007/s40242-021-1054-1

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To meet the demand for long-range electric vehicles with high-energy-density batteries, the solid-state batteries(SSBs) have attracted ever-increasing attention due to their enormous potential in affording the energy density greater than 400 W·h/kg. As the key materials, the solid electrolytes can be classified as inorganic electrolyte and organic electrolyte. The former usually has high ionic conductivity, good stability and mechanical properties, whereas being heavy and brittle. The latter is usually flexible, light and easy to mass produce, nevertheless has poor ionic conductivity and stability. Thus, the combination of the organic and the inorganic electrolytes for the composite membranes has become the inevitable trend to achieve the high energy density and safety of lithium batteries. From the perspective of practical application, this paper discusses how to construct the ideal organic-inorganic composite solid electrolyte with low areal specific resistance, thin texture, wide electrochemical window and high safety for applicable SSBs. Furthermore, the critical challenges and future development directions are prospected for the composite solid electrolytes.



Letter

Hierarchical Porous Carbon Nanotube Spheres for High-performance K-O₂ Batteries

DOU Yaying, ZHANG Yantao, GUO Feng, SHEN Yanbin, CHEN Gang, WEI Yingjin, XIE Zhaojun, ZHOU Zhen

2021, 37(2):  254-258.  doi:10.1007/s40242-021-0423-0

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In view of the ever-growing pressure for green gas emission reduction, there is an urgent need for renewable energy systems. Rechargeable alkali metal-oxygen batteries, especially lithium-oxygen(Li-O₂) batteries, are deemed the most promising energy storage systems because of their higher theoretical energy density than that of current lithium-ion batteries^[1—5]. However, their practical application is seriously hindered by the active oxygen intermediates(O₂^-, LiO₂, and ¹O₂) and the insulating Li₂O₂ product^[6,7]. The former is destructive to carbon materials, and the latter is dependent on electrocatalysts or redox mediators^[8—10]. Therefore, although carbon-based materials have many unique properties, such as high electronic conductivity, light mass and low cost, they are not practical air cathodes for Li-O₂ batteries. Instead of forming peroxide species, potassium-oxygen(K-O₂) and sodium-oxygen(Na-O₂) batteries enable a single-electron redox process of M⁺+O₂+ e^-←→MO₂(M=K or Na). This provides an elegant strategy to enhance the oxygen reduction reaction(ORR) and oxygen evolution reaction(OER) kinetics, thereby greatly decreasing overpotential and improving round-trip efficiency(>90%) even without any electro-catalyst^[11—15]. Obviously, it paves an exciting avenue to use carbon materials in metal-O₂ batteries, which can significantly reduce the cost and further increase the energy density of batteries. Besides, the replacement of Li with abundant Na and K also makes large-scale implementation more feasible^[16]. Unlike Na-O₂ batteries, where the discharge products(NaO₂, Na₂O₂, Na₂O₂·H₂O, or mixtures) vary significantly with the operating conditions, KO₂ with higher stability(ΔG_r of KO₂: -239.4 kJ/mol) has been identified as the sole discharge product in K-O₂ batteries^[15,17]. A recent review has systema-tically summarized the characteristics and advantages of K-O₂batteries^[18], and emphasized that K-O₂ batteries are the only system that does not produce ¹O₂, which reduces the parasitic reactions related to electrolyte/electrode decomposition. Therefore, K-O₂ batteries offer unique advantages in the family of superoxide-based metal-O₂ batteries.



Articles

Self-crystallized Interlayer Integrating Polysulfide-adsorbed TiO₂/TiO and Highly-electron-conductive TiO for High-stability Lithium-Sulfur Batteries

YANG Xinzhe, QIN Tingting, ZHANG Xiaoyu, LIU Xiaofei, WANG Zizhun, ZHANG Wei, ZHENG Weitao

2021, 37(2):  259-264.  doi:10.1007/s40242-020-0310-0

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Low-cost lithium sulfur(Li-S) batteries afford preeminent prospect as a next-generation high-energy storage device by virtue of great theoretical capacity. Nevertheless, their applications are restricted by some challenging technical barriers, such as weak cycling stability and low poor-conductivity sulfur loading ori-ginated in notorious shuttling effect of polysulfide intermediates. Herein, free of any complicated compositing process, we design an interlayer of carbon fiber paper supported TiO₂/TiO to impede the shuttle effect and enhance the electrical conductivity via physical isolation and chemical adsorption. Such a self-crystallized homogeneous interlayer, where TiO₂/TiO enables absorbing lithium polysulfides(LiPSs) and TiO plays a key role of high-electron-conductivity exhibited ultrahigh capacities(1000 mA·h/g at 0.5 C and 900 mA·h/g at 1 C) and outstanding capacity retention rate(97%) after 100 cycles. Thus, our design provides a simple route to suppress the shuttle effect via self-derived evolution Li-S batteries.



Design and Construction of 3D Porous Na₃V₂(PO₄)₃/C as High Performance Cathode for Sodium Ion Batteries

HOU Baoxiu, MA Linlin, ZANG Xiaohuan, SHANG Ningzhao, SONG Jianmin, ZHAO Xiaoxian, WANG Chun, QI Jian, WANG Jiangyan, YU Ranbo

2021, 37(2):  265-273.  doi:10.1007/s40242-021-0433-y

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An easy and delicate approach using cheap carbon source as conductive materials to construct 3D sequential porous structural Na₃V₂(PO₄)₃/C(NVP/C) with high performance for cathode materials of sodium ion battery is highly desired. In this paper, the NVP/C with 3D sequential porous structure is constructed by a delicate approach named as “cooking porridge” including eva-poration and calcination stages. Especially, during evaporation, the viscosity of NVP/C precursor is optimized by controlling the adding quantity of citric acid, thus leading to a 3D sequential porous structure with a high specific surface area. Furthermore, the NVP/C with a 3D sequential porous structure enables the electrolyte to interior easily, providing more active sites for redox reaction and shortening the diffusion path of electron and sodium ion. Therefore, benefited from its unique structure, as cathode material of sodium ion batteries, the 3D sequential porous structural NVP/C exhibits high specific capacities(115.7, 88.9 and 74.4 mA·h/g at current rates of 1, 20 and 50 C, respectively) and excellent cycling stability(107.5 and 80.4 mA·h/g are remained at a current density of 1 C after 500 cycles and at a current density of 20 C after 2200 cycles, respectively).



Improved Initial Charging Capacity of Na-poor Na_0.44MnO₂ via Chemical Presodiation Strategy for Low-cost Sodium-ion Batteries

ZHOU Xi, LAI Yangyang, WU Xiangjiang, CHEN Zhongxue, ZHONG Faping, AI Xinping, YANG Hanxi, CAO Yuliang

2021, 37(2):  274-279.  doi:10.1007/s40242-021-0438-6

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Sodium-ion batteries(SIBs) are promising for grid-scale energy storage applications due to the natural abundance and low cost of sodium. Among various Na insertion cathode materials, Na_0.44MnO₂ has attracted the most attention because of its cost effectiveness and structural stability. However, the low initial charge capacity for Na-poor Na_0.44MnO₂ hinders its practical applications. Herein, we developed a facile chemical presodiated method using sodiated biphenly to transform Na-poor Na_0.44MnO₂ into Na-rich Na_0.66MnO₂. After presodiation, the initial charge capacity of Na_0.44MnO₂ is greatly enhanced from 56.5 mA·h/g to 115.7 mA·h/g at 0.1 C(1 C=121 mA/g) and the excellent cycling stability(the capacity retention of 94.1% over 200 cycles at 2 C) is achieved. This presodiation strategy would open a new avenue for promoting the practical applications of Na-poor cathode materials in sodium-ion batteries.



Synthesis and Electrochemical Investigation of O3-Type High-nickel NCM Cathodes for Sodium-ion Batteries

CHEN Yawei, WANG Shiyang, JIE Yulin, LEI Zhanwu, CAO Ruiguo, JIAO Shuhong

2021, 37(2):  280-285.  doi:10.1007/s40242-021-0441-y

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S odium ion batteries(SIBs) are promising energy storage devices for smart grid applications due to their low cost and the high abundance of sodium, but few cathode materials of SIBs with high energy density are available for practical applications. Herein, a series of NaNCM ternary materials(NCM=nickel-cobalt-manganese) is obtained by solid- phase reaction with well-regulated temperature and other reaction conditions. XRD results show that impure NiO phase is more likely to occur under high nickel content. The cross-section SEM indicates that the primary particles in the electrode materials are radially distributed along the radial direction, and the internal porous structure is conducive to the infiltration of electrolyte. The initial specific capacities of Na[Ni_0.68Co_0.10Mn_0.22]O₂(NaNCM712), Na[Ni_0.6Co_0.2Mn_0.2]O₂(NaNCM622) and Na[Ni_0.4Co_0.3Mn_0.3]O₂(NaNCM433) at 0.2 C are 165.5, 153.1 and 146.8 mA·h/g, and the corresponding capacity retention rates are 63.2%, 78.5% and 71.7% after 100 cycles. NaNCM712 possesses the highest initial specific capacity, and NaNCM433 delivers the best rate capability. The rate capabilities of high-nickel and low-cobalt NaNCM cathodes need to be further improved. Moreover, ex-situ XRD pattern reveals the structure evolution (from O3 type to P2 type) during a long cycling charge and discharge process.



Multilayer Porous Vanadium Nitride Microsheets Anodes for Highly Stable Na-ion Batteries

HU Tao, YANG Weiwei, WANG Cheng, BU Yali, JIN Feng, ZHANG Dongwen, GU Min, LIU Wenhui, LIANG Qinghua, LIU Ruiqing, FENG Xiaomiao, MA Yanwen

2021, 37(2):  286-292.  doi:10.1007/s40242-021-0443-9

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Sodiumion batteries(SIBs) have attracted intensive attention as promising alternative to lithium-ionbatteries(LIBs) for large scale energy storage systems because of low cost of sodium, similar energy storage mechanism and the reasonable performance. However, it is still a great challenge to search and design a robust structure of anode materials with excellent cycling stability and high rate capability for SIBs. Herein, multilayer porous vanadium nitride (VN) microsheets are synthesized through a facile and scalable hydrothermal synthesis-nitrogenization strategy as an effective anode material for SIBs. The multilayer porous VN microsheets not only offer more active sites for fast Na⁺ insertion/extraction process and short diffusion pathway, but also effectively buffer the volume change of anode due to more space in the multilayer porous structure. The large proportions of capacitive behavior imply that the Na⁺ charge storage depends on the intercalation pseudocapacitive mechanism. The multilayer porous VN microsheets electrodes ma-nifest excellent cycling stability and rate capability, delivering a discharge capacity of 156.1 mA·h/g at 200 mA/g after 100 cycles, and a discharge capacity of 111.9 mA·h/g at 1.0 A/g even after 2300 cycles with the Coulombic efficiency of nearly 100%.



Improving the Catalytic Efficiency of NiFe-LDH/ATO by Air Plasma Treatment for Oxygen Evolution Reaction

LEI Chong, LI Wenzheng, WANG Gongwei, ZHUANG Lin, LU Juntao, XIAO Li

2021, 37(2):  293-297.  doi:10.1007/s40242-021-0447-5

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Developing efficient catalysts toward the oxygen evolution reaction(OER) is important for water splitting and rechar-geable metal-air batteries. Although NiFe oxides are consi-dered as potentially applicable catalysts in the alkaline media, there are still a limited numbers of researches working on membrane electrode assembly(MEA) fed with pure water due to their poor electrical conductivity. In this work, antimony doped tin oxide(ATO) has been employed as conductive supports where NiFe layered double hydroxide uniformly dispersed[named NiFe-LDH(layered double hydroxide)/ATO]. The catalysts have been synthesized by a one-step co-precipitation method, and then NiFe-LDH/ATO-air plasma was obtained through mild air plasma treatment. According to XPS analysis, binding energies of Ni_2p and Fe_2p were shifted negatively. Moreover, a new signal of low oxygen coordination appeared on O_1s spectrum after air plasma treatment. These XPS results indicated that oxygen vacancies(O_v) were generated after air plasma treatment. Electrochemical mea-surement indicated that the vacancy-rich NiFe-LDH/ATO-air plasma exhibited better performance than NiFe-LDH/ATO not only in 1 mol/L KOH solutions but also in an alkaline polymer electrolyte water electrolyzer(APEWE) fed with deionized water. This work provides a feasible way to design practical catalysts used in electrochemical energy conversion systems by choosing corrosion resistance supports and defect engineering.



Stabilizing the Electrochemistry of Lithium-Selenium Battery via In situ Gelated Polymer Electrolyte: A Look from Anode

WANG Wen-Peng, ZHANG Juan, LI Xue-Ting, YIN Ya-Xia, XIN Sen, GUO Yu-Guo

2021, 37(2):  298-303.  doi:10.1007/s40242-021-0448-4

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Li metal possesses a high theoretical specific capacity, high electronic conductivity, and a low electrochemical potential, making it a promising anode material for building next-gene-ration rechargeable metal batteries. In case conventional liquid electrolytes were used, and the anode using Li metal has been hindered by unstable(electro)chemistry at Li/electrolyte interface and the accompanied dendrite issue. Specifically, for the Li-Se batteries, the dissolution and shuttle of polyselenide intermediates lead to the deposition of poorly-conductive species on the anode, which further aggravates the chemical environment at the anode. In this work, we proposed to stabilize the Li-Se electrochemistry by constructing a gel polymer electrolyte via in situ gelations of conventional ether-based electrolytes at room temperature. The results demonstrate that the in situ gelated electrolyte helps to build electrochemically stable electrode/electrolyte interfaces and promote the efficient transfer of charge carriers across the interface. Compared with the liquid electrolytes, the gelated electrolyte shows improved chemical compatibility with the Li metal anode, which effectively alleviates the unfavorable side reactions and dendrite formation at the anode/electrolyte interface, and the polyselenide shuttle from the cathode to the anode. As a result, the Li-Se battery shows a higher Coulombic efficiency and improved cycling performance.



Small Things Make a Big Difference: the Small-molecule Cross-linker of Robust Water-soluble Network Binders for Stable Si Anodes

WANG Dong, LI Zhenwei, ZHANG Qian, LIU Jie, YANG Yu, HAN Jishu, WANG Lei

2021, 37(2):  304-310.  doi:10.1007/s40242-021-1003-z

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Silicon(Si) with high theoretical capacity has attracted tremendous attention as the next-generation anode material for Li-ion batteries, but the huge expansion during cycling restricts its practical application. Designing a low-cost, accessible robust network binder is a facile and effective approach to suppress the volume change effect and achieve the commercial application of Si anodes. Different previous studies focused on the network binder macromolecule main chain, this manuscript pays attention to the study of small-molecule cross-linker. Herein, cross-linked network binders using alginate acid and two kinds of cross-linkers, i.e., D-sorbitol and isosorbide(Alg-DS and Alg-IS binders) are synthesized. It was found that not only the chemical structure of the cross-linker but also the physicochemical property, such as melting point affect greatly the mechanical properties of the network binder. As a result, the Si anode with an Alg-DS binder dried below the melting point of DS shows the best cycling stability with a high capacity of 2249.8 mA·h/g and a retention rate as high as 95.9% after 100 cycles. This study gives a new view to design robust network binders for stable Si anodes.



Synthesis of SnS₂ Ultrathin Nanosheets as Anode Materials for Potassium Ion Batteries

HU Rong, FANG Yongzheng, LIU Xiaoyu, ZHU Kai, CAO Dianxue, YI Jin, WANG Guiling

2021, 37(2):  311-317.  doi:10.1007/s40242-021-0017-x

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Potassium(K) ion batteries present their promising application for large-scale energy storage systems with cost-effective characteristic. Unfortunately, the large K ion radius results in sluggish K ion diffusion kinetics and volume expansion of the electrode during the K ion insertion/extraction process. It is a challenge to explore capable anode materials with remarkable K ion storage ability. Herein, we design and prepare SnS₂ ultrathin nanosheets via a facile hydrothermal process. When severing as anode materials for K ion batteries with optimized electrolyte, SnS₂ presents an improved capacity and rate ability. The capable electrochemical performance is ascribed to the reduced ion diffusion pathway and capacitor-dominated K-ion storage process. In addition, the K ion storage mechanism of SnS₂ is investigated by the ex-situ X-ray diffraction technique.



Hexagonal FeNi₂Se₄@C Nanoflakes as High Performance Anode Materials for Sodium-ion Batteries

MA Cui, QIU Licheng, BAO Jian, ZHOU Yongning

2021, 37(2):  318-322.  doi:10.1007/s40242-021-1030-9

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Metal selenides have drawn significant attention as pro-mising anode materials for sodium-ion batteries(SIBs) owing to their high electronic conductivity and reversible capacity. Herein, hexagonal FeNi₂Se₄@C nanoflakes were synthesized via a facile one-step hydrothermal method. They deliver a reversible capacity of 480.7 mA·h/g at 500 mA/g and a high initial Coulombic efficiency of 87.8%. Furthermore, a discharge capacity of 444.8 mA·h/g can be achieved at 1000 mA/g after 180 cycles. The sodium storage mechanism of FeNi₂Se₄@C is uncovered. In the discharge process, Fe and Ni nanoparticles are generated and distri-buted in Na₂Se matrix homogeneously. In the charge process, FeNi₂Se₄ phase is formed reversibly. The reversible phase conversion of FeNi₂Se₄@C during cycling is responsible for the excellent electrochemical performance and enables FeNi₂Se₄@C nanoflakes promi-sing anode materials for SIBs.



Solution-based Preparation of High Sulfur Content Sulfur/Graphene Cathode Material for Li-S Battery

ZHANG Chen, LIU Donghai, GENG Chuannan, HUA Wuxing, TANG Quanjun, LING Guowei, YANG Quan-Hong

2021, 37(2):  323-327.  doi:10.1007/s40242-021-0036-7

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Practical Li-sulfur batteries require the high sulfur loading cathode to meet the large-capacity power demand of electrical equipment. However, the sulfur content in cathode materials is usually unsatisfactory due to the excessive use of carbon for improving the conductivity. Traditional cathode fabrication strategies can hardly realize both high sulfur content and homogeneous sulfur distribution without aggregation. Herein, we designed a cathode material with ultrahigh sulfur content of 88%(mass fraction) by uniformly distributing the water dispersible sulfur nanoparticles on three-dimensionally conductive graphene framework. The water processable fabrication can maximize the homogeneous contact between sulfur nanoparticles and graphene, improving the utilization of the interconnected conductive surface. The obtained cathode material showed a capacity of 500 mA·h/g after 500 cycles at 2.0 A/g with an areal loading of 2 mg/cm². This strategy provides possibility for the mass production of high-performance electrode materials for high-capacity Li-S battery.



Anti-corrosive Hybrid Electrolytes for Rechargeable Aqueous Zinc Batteries

WANG Jia, QIU Huayu, ZHAO Zhiming, ZHANG Yuchen, ZHAO Jingwen, MA Yinglei, LI Jiedong, XING Min, LI Guicun, CUI Guanglei

2021, 37(2):  328-334.  doi:10.1007/s40242-021-1041-6

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Aqueous zinc(Zn)-metal cells with cost-effective components and high safety have long been a promising large-scale energy storage system, but Zn anodes are intrinsically unstable with common aqueous electrolytes, causing substantial underutilization of the theoretical capacity. In this work, we report a strictly neutral aqueous Zn electrolyte at a low cost by leveraging the dynamic hydrolysis equilibrium of a dual-salt Zn(Ac)₂/NaAc(Ac: CH₃COO^-) formulation. With the pH regulation, the corrosion and hydrogen evolution encountered in Zn anodes can be suppressed significantly. This hybrid aqueous electrolyte not only enables dendrite-free Zn plating/stripping at a nearly 95% Coulombic efficiency[an increase of 24% compared to that of the single-salt 1 mol/L Zn(Ac)₂ electrolyte], but also supports the reversible operation of Zn cells paired with either Na₃V₂(PO₄)₃ or iodine cathodes—the former delivers a high output voltage of 1.55 V with an energy level of 99.5 W·h/kg(based on the mass of the cathode), and the latter possesses a high specific capacity of 110.9 mA·h/g while yielding long-term cyclability(thousands of cycles). These findings open up a new avenue of modifying practical electrolytes having targeted properties to stabilize multivalent metal anodes.



Highlight

A Mechanical Single-molecule Potentiometer Based on Foldamer

ZHAO Zhikai, WANG Qingling, XIANG Dong

2021, 37(2):  335-336.  doi:10.1007/s40242-021-1094-6

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Molecular potentiometers that can indicate displacement-conductance relationship and predict the molecular conductance are of significant importance towards the real application of molecule-based devices but rarely developed so far. To this end, Li et al. design a single-molecule potentiometer based on ortho-pentaphenylene derivatives. They demonstrated that these pseudoelastic molecules can be stretched and compressed by the mechanical force of the Au electrode along with a dramatically variable conductance by up to two orders of magnitude, demonstrating the great potential as angstrom-scale single-molecule potentiometers. This work has been published in Nature Communications, 2021.