EFFICIENCY STUDIES OF GALINSOGA PARVIFLORA PIGMENTS AS A SENSITIZER IN PT FREE GRAPHENE OXIDE/NICKEL OXIDE COUNTER ELECTRODE: DYE SENSITIZED SOLAR CELL APPLICATIONS

Abstract

An easily available Galinsoga Parviflora (GP) natural dye has been used as natural sensitizers for dye sensitized solar cell (DSSC). Graphene oxide (GO) is one of the most efficient materials for solar cells, supercapacitor and sensing applications because of its unique properties. It is prepared from natural graphite flakes by modified Hummer’s method. Graphene oxide/nickel oxide (GO/NiO) nanocomposites are prepared by chemical precipitation method. The different concentrations of nickel oxide nanoparticles (5:1, 5:2 and 5:3) are embellished on the GO surface. The synthesis of these nanocomposites are confirmed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), energy dispersive X-ray spectroscopy (EDX), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM) and high resolution transmission electron microscopy (HR-TEM). The XRD results confirmed that the nickel oxide nanoparticles are coated on the graphene oxide surface and the crystallite size of GO/NiO (5:1, 5:2 and 5:3) nanocomposites are found to be around 19 nm, 21.3 nm and 23 nm respectively. The electrochemical activity of the prepared nanocomposites is investigated by cyclic voltammetry (CV) technique. The power conversion efficiency is measured using a light source simulated with an intensity of 100 mW/cm2. The conversion efficiency of prepared sandwich type dye sensitized solar cell (5:1, 5:2 and 5:3) is 0.9%, 1.3% and 1.65% respectively.