Fabrication of dye sensitized solar cells with cost-effective quaternary sulfide counter electrode

Abstract

The objective of the present study is to develop a platinum (Pt)-free counter electrodes with quaternary sulfide Cu2ZnSnS4 (CZTS) and also to study the effect of compact layer on device performance. CZTS nanoparticles were synthesized by solvothermal process and extensive characterization using XRD, Raman Spectroscopy, FEG-SEM and FEG-TEM was carried out. Synthesized CZTS particles were in the form of nanosheets, consisting of nanorods, which was confirmed by FEG-TEM. CZTS films were coated on FTO (Fluorine doped tin oxide) substrate by inexpensive drop casting method. Electrochemical catalytic activity of CZTS counter electrode was studied using cyclic voltammetry. Dye sensitized solar cells (DSSC) fabricated with CZTS as counter electrode showed photo conversion efficiency of 7.56% as compared to Pt based counter electrode 8.34 % efficiency. The charge transport at CZTS-electrolyte interface was studied with the help of electrochemical impedance spectroscopy.