Valence electronic engineering of hollow-nanocube-structured CoFeNi-layered double hydroxides for highly efficient oxygen evolution

Abstract

The sluggish kinetics of oxygen evolution reaction (OER) and the high-cost of catalysts currently limit the large-scale industrialization of hydrogen production through water electrolysis, so developing efficient and inexpensive catalysts is a top priority. Herein, we employed a facile solvent method to synthesize a well-defined hollow nanocube-structured CoFeNi layered double hydroxide (LDH) with an optimized valence electronic structure of metal sites as an efficient electrocatalyst for accelerating the kinetics of OER. The optimal catalyst with the regulated valence electronic structure exhibited a strong synergistic catalytic effect and an excellent activity and stability. It achieved a lower overpotential of 294 mV at 100 mA cm−2, and high durability exceeding 100 h at 1 A cm−2, surpassing the performance of commercial Ir-/Ru-based catalysts. The optimized the coordination environment and valence electronic structure of metal sites can definitely serve as active centers for triggering OER, thereby improving the intrinsic electrocatalytic performance.