Chemical Research in Chinese Universities ›› 2013, Vol. 29 ›› Issue (3): 596-599.doi: 10.1007/s40242-013-2461-8

• Articles • Previous Articles     Next Articles

Synthesis and Photovoltaic Properties of Non-fullerene Solution Processable Small Molecule Acceptors

LI Hui, LIU Zhao-yang, ZHANG Xiao-yu, YAO Shi-yu, WEN Shan-peng, TIAN Wen-jing   

  1. State Key Laboratory of Supramolecular Structure and Materials, Jilin University, Changchun 130012, P. R. China
  • Received:2012-11-29 Revised:2013-01-28 Online:2013-06-01 Published:2013-05-15
  • Contact: Wenjing Tian E-mail:wjtian@jlu.edu.cn
  • Supported by:

    Supported by the State Key Development Program for Basic Research of China(No.2009CB623605), the National Natural Science Foundation of China(No.20874035), the “111” Project of China(No.B06009) and the Project of Organic Polymer/Inorganic Nanocomposite Solar Cell Materials of Jilin Province, China(No.20080305).

Abstract:

Two non-fullerene small molecules, BT-C6 and BT-C12, based on the vinylene-linked benzothiadiazole- thiophene(BT) moiety flanked with 2-(3,5,5-trimethylcyclohex-2-en-1-ylidene)malononitrile have been synthesized and characterized by solution/thin film UV-Vis absorption, photoluminescence(PL), and cyclic voltammetry(CV) measurements. The two molecules show intense absorption bands in a wide range from 300 nm to 700 nm and low optical bandgaps for BT-C6(1.60 eV) and for BT-C12(1.67 eV). The lowest unoccupied molecular orbital(LUMO) levels of both the molecules are relatively higher than that of [6,6]-phenyl C61 butyric acid methyl ester(PCBM), promising high open circuit voltage(Voc) for photovoltaic application. Bulk heterojunction(BHJ) solar cells with poly(3-hexylthiophene) (P3HT) as the electron donor and the two molecules as the acceptors were fabricated. Under 100 mW/cm2 AM 1.5 G illumination, the devices based on P3HT:BT-C6(1:1, mass ratio) show a power conversion efficiency(PCE) of 0.67%, a short-circuit current(Jsc) of 1.63 mA/cm2, an open circuit voltage(Voc) of 0.74 V, and a fill factor(FF) of 0.56.

Key words: Non-fullerene small molecule, Electron acceptor, Bulk heterojunction