Interfacial engineering regulated by CeOx to boost efficiently alkaline overall water splitting and acidic hydrogen evolution reaction

Development of a low-cost and durable bifunctional electrocatalyst with high catalytic activity by hybridizing rare earth metal and non-noble metal is of utmost significance.Herein,a bifunctional electrocatalyst consisting of MoO2and CeOxheterostructure is synthesized via interfacial engineering.Particularly,due to its unique hetero-interface with abundant oxygen vacancies,the MoO2-CeOx/NF is able to exhibit outstanding hydrogen evolution reaction(HER) performance with an overpotential of 26 mV at 10 mA cm-2,and a preferable oxygen evolution reaction(OER) overpotential of 272 mV at 100 mA cm-2in 1 M KOH.The recorded HER and OER overpotentials of MoO2-CeOx/NF are clearly smaller than those of Pt/C(HER overpotential of 27 mV) and RuO2(OER overpotential of 393 mV) at the same current density.More importantly,MoO2-CeOx/NF can also exhibit good HER activity with an overpotential of 50 mV at 10 mA cm-2in acidic media.Thus,it is expected that this work can offer a new approach in the realization of high-catalytic alkaline overall water splitting and acidic HER performance through the rational design of rare-earth metal and non-noble metal heterostructure.