Morphological impact of ZnO nanoparticle on MEHPPV:ZnO based hybrid solar cell

Abstract

In this study, we have synthesized semiconducting ZnO nanoparticles (NP) of different morphology in solvothermal route, by using different capping reagents and applied it as an acceptor in poly(2-methoxy-5(2-ethylhexyloxy)-phenylene-vinylene (MEHPPV):ZnO NP based hybrid photovoltaic devices. Material properties of ZnO NP of different morphology and the compositions were studied with the help of X-ray diffraction, scanning electron microscopy, fourier transform infrared and thermo gravimetric analysis. The direct band gap energies of flower, sphere and rod-like ZnO NP were calculated as 3.68, 3.15 and 3.25 eV by using Tauc’s plot with the help of UV–Vis absorption. We have studied different material properties of MEHPPV:ZnO composite to check their applicability as an active layer of hybrid solar cell. Photo-luminescence (PL) spectra of the composite materials were recorded to check PL energy quenching which is quite noticeable in case of sphere-like nanoparticle. Finally the hybrid solar cell of the structure ITO/PEDOT:PSS/MEHPPV:ZnO/Al has been fabricated and studied. From the current density (J)–voltage (V) characteristic, we have found that the solar cell fabricated with ZnO sphere-like structure gives better result.