The role of graphene oxide in ZnO:Al/silicon solar cells

A widely used approach to reduce the charge recombination and improve the performance of a silicon based Schottky barrier solar cell (SBSC) is to use an interfacial layer between metal and Si. In the present work we have investigated the role of graphene oxide (GO) as interfacial layer for p doped Si (p-Si) based SBSC utilizing AZO (Aluminum doped ZnO) as transparent top contact. The not obvious compatibility of the different layers combined in the solar device results clear from the improvement of all the electrical parameters measured in the AZO/GO/p-Si solar cell respect to the simple AZO/p-Si device used as reference. In particular dark IV characterization put in evidence the majority carrier blocking properties of the GO in this type of structure, with an increment of 140 meV in the barrier height respect to the device without GO, resulting in a 100% enhancement in the final solar cell efficiency.