Skeleton-coated CoCu-Based bimetal hollow nanoprisms as High-Performance electrocatalysts for oxygen evolution reaction

[Display omitted] •The morphology of hollow nanoprisms N-Co-Cu-S-x HNs synthesized by the self-templating method can be controlled.•Cu was successfully introduced to modulate the electronic structure of the Co center to improve the electrical conductivity.•The N-containing C skeleton protects internal active sites of the catalysts to stabilize the OER activity.•N-CoCu-S-0.25 exhibits exciting catalytic activity and durability (27 h). CoSx materials with high catalytic activity are considered as promising HER electrocatalysts, but their inherent low electrical conductivity and easy loss of active sites have greatly limited their applications in OER electrocatalysis. Herein, we present a convenient method to synthesize Co-Cu hollow nanoprisms after wrapping and calcining with trithiocyanuric acid (C3H3N3S3) (denoted N-Co-Cu-S-x HNs). The results showed that Cu doping modified the charge density of Co center, leading to the enhancement of the intrinsic activity of the Co3S4 active center, meanwhile wrapping trithiocyanuric acid on the surfaces and calcinating to form N-containing C skeleton as a flexible substrate to encapsulate the catalysts, which effectively protected the active sites inside the catalysts. Notably, the OER catalyst that was optimized by adjusting the metal ratio and controlling the trithiocyanuric acid incorporation exhibited a low overpotential of 306 mV under a current density of 10 mA cm−2 and showed a superior durability of more than 27 h. This work may provide some insights into the preparation of oxygen evolution reaction catalysts with excellent performance through doping transition metals and protecting the internal active sites strategies.