Significantly enhanced OER and HER performance of NiCo-LDH and NiCoP under industrial water splitting conditions through Ru and Mn bimetallic co-doping strategy

Abstract

High-performance electrocatalysts play a crucial role in promoting the development of industrial water splitting. Reasonable electronic structure design is key to improving the performance of electrocatalysts. This study proposed a Ru and Mn bimetallic co-doping strategy to achieve rational electronic structure design of both NiCo-LDH (RMNCL) and NiCoP (RMNCP). Specifically, we first obtained Ru and Mn bimetallic co-doped NiCo-LDH through a one-step electrodeposition, exhibiting superior catalytic activity (342 mV at 500 mA/cm2) for the oxygen evolution reaction in alkaline solution. Subsequently, we prepared Ru and Mn co-doped NiCoP by a simple phosphorization treatment of RMNCL, demonstrating impressive low overpotentials (200 mV at 500 mA/cm2) for hydrogen evolution reaction in alkaline solution. Furthermore, we constructed an anion exchange membrane electrolyzer using the prepared catalysts, achieving a high current density of 1 A/cm2 with only 2 V, maintaining stability over a prolonged 100 h duration. Further studies revealed the highly dispersed Ru atoms provided abundant active sites, while Mn modified the electron filling of anti-bonding orbitals in both catalysts, optimizing reactant adsorption. Additionally, multivalent Mn contributed to the improved catalytic performance. This study provides insights into rational electrocatalyst design and lays the foundation for catalyst development with outstanding activity under industrial-scale conditions.