Core-shell heterojunction engineering of Ni0.85Se-O/CN electrocatalyst for efficient OER

Efficient electrocatalysts are of great consideration for lowering the potential barrier for the oxygen evolution reaction (OER). The Ni0.85Se-O/CN multicore core–shell coated structured microspherical electrocatalyst was prepared by a simple hydrothermal method for promoting OER in alkaline solution. With highly conductive Ni0.85Se-O as the core and g-C3N4 with abundant active sites as the shell, the electrocatalyst exhibits excellent catalytic OER performance with a Tafel slope of 82.5 mV dec−1 and an overpotential of 240 mV @ 10 mA cm−2. What’s more, the catalyst exhibits excellent long-term stability, which is facilitated by the protection of the core (Ni0.85Se-O) from corrosion and oxidation by the shell (g-C3N4). In addition, in-depth mechanistic analysis on catalytic activity of materials were performed by density functional theory (DFT). This work highlights the importance of core–shell structural engineering to improve the catalytic activity of materials and provides new possibilities for the progress of Ni-based catalysts in the field of oxygen evolution reaction.