Dye-sensitized solar cell employing chitosan-based biopolymer electrolyte

Abstract

Conductivity and transport properties of a cost-effective and environment friendly chitosan based solid biopolymer electrolytes which form mechanically robust thick film, have been reported here. A maximum ionic conductivity of ∼ 10-4 S/cm has been achieved by optimizing the concentrations of the salt (LiClO4) and the plasticizer (EC) in the biopolymer electrolyte. Ion transport properties of the biopolymer electrolytes are studied from Raman spectroscopy. A dye-sensitized solar cell (DSSC), with a sandwich structure, is fabricated with chemically synthesized ZnO (∼ 60 nm) as the nanoporous semiconductor material coated with Rose Bengal dye as a photosensitizer, the chitosan biopolymer as electrolyte and platinum as counter electrode. Linear Sweep Voltammetry analysis of the DSSCs illustrates the photovoltaic performance of these cells. Without any external addition of redox couple in the biopolymer electrolytic system, a maximum short-circuit current density of JSC = 0.556 mA/cm2 and open-circuit voltage Voc = 0.605 V with power conversion efficiency 0.051 % is achieved by the DSSC.