Enhanced charge separation and transfer through Fe2O3/ITO nanowire arrays wrapped with reduced graphene oxide for water-splitting

Abstract This work reports the synthesis and investigation of reduced graphene oxide (rGO)-wrapped ITO@Fe 2 O 3 (rGO-ITO@Fe 2 O 3 ) core-shell nanowire arrays for water splitting, in which Fe 2 O 3 nanorods are primary light-absorber, ITO nanowires act as high speed electron conductor and rGO as highly active electrocatalyst. This design considerably reduced the charge transfer and injection resistance, thus decreasing the recombination and improving the oxygen reaction kinetics. As a result, the rGO-ITO@Fe 2 O 3 photoanode yields a photocurrent up to 5.38 mA cm −2 at 0.6 V (versus SCE), which is 3.5 times and 10 times of ITO@Fe 2 O 3 and Fe 2 O 3 in the same situation. The rGO-ITO@Fe 2 O 3 photoanode also exhibits an excellent photoelectrochemical stability and there is no obvious degradation after 60 min. Our work has provided an efficient strategy to improve the energy conversion efficiency and life-time of water splitting materials.