Synthesis of metal free organic dyes: Experimental and theoretical approach to sensitize one-dimensional cadmium sulphide nanowires for solar cell application

Abstract

Synthesis of metal-free organic dyes PDR and PDP based on the phenothiazine core unit have been attempted through solution chemistry approach and anchored on to one dimensional cadmium sulphide nanowires (CdS NWs) to be used as light harvesters in dye sensitized solar cell (DSSC) device application. Simple and cost effective solution chemistry approach leads to enable CdS NWs interconnected nano network. Synthesized dyes have been investigated through optical and electrochemical studies in addition to theoretical calculations using density functional theory (DFT). Dye anchored CdS films cover wider light absorption than bare CdS in the visible part of solar spectrum. The complete device configuration has been assembled as FTO/CdS compact/CdS NWs/Organic dye/electrolyte/Platinum electrode. PDR and PDP sensitized CdS NWs yield 0.24 and 0.28% efficiency which are 2.36 and 2.77 times as compared to bare CdS NWs (0.10%) with sun light of standard conditions of illuminations. External quantum efficiency enhancement is well supported with the obtained results and correlated well with the absorption studies. The present work successfully demonstrates the use of novel synthesized organic dyes as light harvesters.