CTAB-Assisted Hydrothermal Synthesis of CoFeMo Layered Double Hydroxides for Efficient Oxygen Evolution Reactions

Abstract

The sluggish kinetics of the oxygen evolution reaction (OER), one of the half-reactions in water electrolysis, severely constrains the large-scale implementation of this technology. Therefore, identifying electrocatalysts with superior OER performance is of critical importance. In this study, a CTAB-assisted hydrothermal method was employed to synthesize CoFeMo layered double hydroxide (LDH) nanosheets on nickel foam (NF) to achieve enhanced OER activity. The incorporation of Mo resulted in an increased number of active sites and improved electrical conductivity, yielding overpotentials of 164 and 265 mV at 10 and 50 mA cm⁻², respectively surpassing the performance of both CoFe LDH/NF and RuO₂/NF, as well as most previously reported OER catalysts. The exceptional activity was attributed to the high valence state of Mo, which stabilizes neighboring metals through electronic structure modulation. In addition, the presence of the cationic surfactant CTAB during the hydrothermal process effectively suppressed metal agglomeration and regulated the morphology. Overall, this work demonstrates that CoFeMo LDH/NF synthesized via CTAB-assisted hydrothermal methods serves as a highly effective electrocatalyst for oxygen evolution reactions.