Electrochimica Acta, Vol.142, 68-75, 2014
PEDOT:PSS and glucose assisted preparation of molybdenum disulfide/single-wall carbon nanotubes counter electrode and served in dye-sensitized solar cells
A flower-like structure complexes of molybdenum disulfide/single-wall carbon nanotubes (MoS2/SWCNTs) are for the first time synthesized with glucose and poly (3, 4-ethylenedioxythiophene): poly (styrenesulfonate) (PEDOT:PSS) assisted (G-P-A) by the use of an in situ hydrothermal route, and proposed as counter electrode (CE) catalyst for Pt-free dye-sensitized solar cells (DSSCs). The DSSC assembled with the (G-P-A) MoS2/SWCNTs CE exhibits a high photo-electric conversion efficiency of 8.14% under the illumination of 100 mW.cm(-2), comparable to that of the DSSC Pt-based (7.78%). Furthermore, the surface morphology of the (G-P-A) MoS2/SWCNTs complexes with flower-like structure is confirmed by using the scanning and transmission electron microscopes (SEM). The superior structural characteristic along with 3D large interconnected interstitial volume is advantageous fast mass transport for the electrolyte, and enables the (G-P-A) MoS2/SWCNTs CE to speed up the reduction of triiodide to iodide. The electrochemical performance of the sample is analyzed from cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). It indicates that the (G-P-A) MoS2/SWCNTs CE possesses excellent electrocatalytic activity in iodide/triiodide electrolyte and lower charge transfer resistance of 1.46 Omega.cm(2) compared to the Pt electrode (2.44 Omega.cm(2)). Sum up, the (G-P-A) MoS2/SWCNTs CE can be considered as a promising alternative CE for Pt-free DSSCs. (C) 2014 Elsevier Ltd. All rights reserved.
Keywords:Poly (3;4-ethylenedioxythiophene):poly(styrenesulfonate);molybdenum disulfide;single-wall carbon nanotubes;dye-sensitized solar cell;photo-electric conversion efficiency