LAUSR

Abstract Designing highly active and robust bifunctional electrocatalysts toward efficient overall water splitting using for novel renewable energy storage and conversion systems is still a challenging task. Here, self-supported bimetallic cobalt-molybdenum nitride with silver nanoparticles decoration (Co-Mo-N@Ag) growth in situ on carbon paper was rationally designed and fabricated for overall water splitting in alkaline media. By virtue of the admirable compositional and structural advantages of exposed enough active sites, regulated favorable electronic structure, and engineered powerful interface synergy effect, the Co-Mo-N@Ag electrode exhibits superior electrocatalytic performance in 1 M KOH. In the details, an excellent oxygen evolution reaction (OER) activity with an extremely low overpotential of 234 mV at 10 mA cm-2 and a small Tafel slope of 54 mV dec-1, as well as a remarkable hydrogen evolution reaction (HER) activity with a low overpotential of 90 mV at 10 mA cm-2 and Tafel slope of 73 mV dec-1 were acquired by Co-Mo-N@Ag. As a result, it takes a low voltage of 1.56 V to reach 10 mA cm-2 in alkaline overall water splitting. This work presents the heterogeneous interfacial structure decorated by silver and provides a feasible method to increase the OER and HER activity of metal nitrides.