Fabrication of PEDOT films via a facile method and their application in Pt-free dye-sensitized solar cells

作者:Li, Yin-Chang; Jia, Song-Ru; Liu, Zhi-Yan; Liu, Xue-Qin*; Wang, Yang; Cao, Ya; Hu, Xiao-Qin; Peng, Cheng-Long; Li, Zhen*
来源:Journal of Materials Chemistry A, 2017, 5(17): 7862-7868.
DOI:10.1039/c7ta00990a

摘要

Poly(3,4-ethylenedioxythiophene) (PEDOT) has attracted much attention in the application of dyesensitized solar cells (DSSCs) due to its outstanding photovoltaic property. PEDOT films were synthesized in a three-electrode system with a direct-current power supply to control the polymerization process, leading to a simplification of the electrochemical polymerization procedure. The morphology of PEDOT can be represented as a micro-sphere with three-dimensional network-like structures aggregated with plenty of nanoparticles. The polymerization voltage, polymerization time and the concentration of 3,4-ethylenedioxythiophene (EDOT) exhibited a significant influence on the photovoltaic characteristics of PEDOT films. Impressively, the DSSCs with optimum PEDOT films as counter electrodes (CEs) reached the highest power conversion efficiency (eta) of 6.401%, which was comparable to that of a cell with platinum (Pt) CEs (6.493%). After modification by reduced graphene oxide (rGO), DSSCs equipped with PEDOT/rGO CEs reached an eta of 7.115%, with an enhancement of 9.58% compared to that of Pt CEs. Thus, the rGO-coated network-like PEDOT can be considered as an economical alternative component to expensive Pt electrodes.