Construction of RuSe2/MoOx hybrid and used as bi-functional electrocatalyst for overall water splitting

Abstract Generally, bi-functionalal electrocatalysts used for overall water splitting (OWS) have good hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) performance. Herein, RuSe2/MoOx composite (RSMC) is constructed through a simple and convenient solid phase reaction (SPR) strategy, and is further studied as a potential electrocatalyst for OWS. At first, we prepared RuO2/MoSe2 composite (RMC) precursor. When the RMC was heat-treated in a N2 atmosphere, the SPR occurred between RuO2 and MoSe2. Therefore, RMC was converted into RuSe2/MoOx composite (RSMC) in-situ, accompanied by the formation of oxygen vacancies (VO) in the MoOx phase. In this work, the overpotential of RSMC-500 (prepared by annealing the RMC precursor at 500 °C in a N2 atmosphere) at 10 mA cm−2 under alkaline conditions (1 M KOH) are 58 (HER) and 270 mV (OER), respectively. When using RSMC-500 as anode and cathode materials to make an electrolytic cell, a low cell voltage of 1.57 V is required under alkaline condition to achieve the current density of 10 mA cm−2. The good performance shows the potential application of RSMC-500 in the field of renewable and clean energy area.