Enhanced photocurrent generation of bio-inspired graphene/ZnO composite films

A bio-inspired photoelectrode was developed by self-assembly of honeycomb graphene oxide films, followed by reduction and in situ growth of ZnO nanorods (NRs). In the nanocomposite film, the graphene substrate shows an elegant macroporous structure of an ordered honeycomb pattern, with uniformly and densely deposited ZnO NRs. In a photoelectric conversion system, the rGO/DODA/ZnO honeycomb film not only significantly improves light-capturing ability, but also provides a direct and stable pathway for rapid electron transport, promoting photoinduced electron-hole separation. Compared to the counterpart of a smooth hybrid film, the honeycomb composite material shows a decreased incident light reflection of 26%, and a three-fold increase in photocurrent. It is envisioned that this facile and scalable fabrication approach, as well as this bio-inspired structure, will open a new avenue for the rational design and engineering of high-performance solar energy conversion devices.