Fabrication of TiO2/RGO/Cu2O heterostructure for photoelectrochemical hydrogen production

Novel heterostructure built from titanium dioxide (TiO2), reduced graphene oxide (RGO) and cuprous oxide (Cu2O) has been successfully designed and prepared for photoelectrochemical hydrogen production. The stepwise introduction of three materials on conductive glass substrate has been realized through hydrothermal and chemical solution deposition methods, respectively. The morphology of Cu2O regularly altered with increasing the amount of Cu2O. The photoelectrochemical performance of heterostructure was systematically investigated, and the synergistic effect of TiO2, RGO and Cu2O was conducive to improving the absorption spectrum range and electron/hole separation, which resulted in the enhancement of photocurrent intensity and incident photon-to-photocurrent efficiency. Electrochemical impedance spectroscopy (EIS) further confirmed that TiO2/RGO/Cu2O heterostructure possessed the lowest charge-transfer resistance, revealing that heterostructure could significantly accelerate the electron mobility compared with bare TiO2. More importantly, the hydrogen production rate of TiO2/RGO/Cu2O heterostructure was up to 631.6 mu mol/h m(2) (radiation intensity: 47 mW/cm(2)) which is almost three times than that of bare TiO2. (C) 2015 Published by Elsevier B.V.