Graphene nanoparticle incorporated CuO thin film for solar cell application

A thin cupric oxide film (CuO), straddled with graphene nanoparticles, is proposed as a promising absorber layer for solar cell application. The influence of the graphene nano-particles on the optical, electrical, and photovoltaic properties of the CuO thin film is investigated in detail. Graphene nano-particles incorporated CuO (G-CuO) film, grown via sol-gel deposition, shows a reduction in the optical transmittance and reflectance, and an enhancement in its electrical conductivity. Photovoltaic properties, investigated through a p-(G-CuO)/n-Si heterojunction cell, shows a significant increase in short circuit current from 0.12 mA/cm2 to 0.82 mA/cm2. The fill factor was also found to increase to 40% from 20%. The significant improvement in efficiency of the G-CuO solar cell is attributed to the synergetic effect provided by graphene in enhancing the absorption of visible light and increasing its electrical conductivity, while concurrently suppressing charge recombination in the bulk semiconductor.