Hybridization of bimetallic cobalt-molybdenum oxide multihole nanosheets with selenium adulteration as advanced bifunctional electrocatalysts for boosting overall water splitting

Electrocatalytic water splitting produces green and pollution-free hydrogen as a clean energy carrier, which can effectively alleviate energy crisis. In this paper, bimetallic and selenium doped cobalt molybdate (Se-CoMoO 4 ) nanosheets with rough surface are resoundingly prepared. The multihole Se-CoMoO 4 nanosheets display ultrathin and rectangular architecture with the dimensions of ∼ 3.5 μm and 700 nm for length and width, respectively. The Se-CoMoO 4 electrocatalyst shows remarkable water electrolysis activity and stability. The overpotentials of oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) are 270 and 63.3 mV at 10 mA cm −2 , along with low Tafel slopes of 51.6 and 62.0 mV dec -1 . Furthermore, the Se-CoMoO 4 couple electrolyzer merely requires a cell voltage of 1.48 V to achieve 10 mA cm −2 current density and presents no apparent attenuation for 30 h. This investigation declares that the hybridization of transition bimetallic oxide with nonmetallic adulteration can afford a tactic for the preparation of bifunctional non-precious metal-based electrocatalysts.