Multifunctional reduced graphene oxide film as electrocatalysts and photothermal layer for broad spectrum solar-enhanced oxygen evolution reaction

Abstract

Solar light-assisted electrocatalysis via photothermal effect has been demonstrated to be an efficient strategy for improving the oxygen evolution reaction (OER) performance. However, the light-to-heat conversion usually occurs in a specific wavelength range, which leads to incomplete solar light utilization with energy loss. Herein, a simple yet effective approach was employed to construct the multifunctional reduced graphene oxide (rGO) film with broad light absorption, which could maximize the use of solar light for generating localized heat that speeds up the transfer of electron and mass in the electrocatalytic OER process. The results indicate that the introduction of solar light lead to the significant improvement of OER activity, in which the overpotential at 10 mA cm-2 and Tafel slope rate is decreased by 93 mV and 62.4 mV/dec, respectively, compared with that without light illumination.