Accelerating water dissociation via modulating charge transfer at the CoMo alloy/CoW layered double hydroxide...

To achieve the design of high-performance hydrogen evolution electrodes, constructing interfaces with multifunctional coupling is a key strategy. It is worth emphasizing that the design and development of alloy/hydroxide integrated electrodes have emerged as a highly prominent research direction, yet such systems still confront considerable and non-negligible challenges. In this study, a distinctive three-dimensional electrocatalyst constructed by CoMo alloy nanoparticles and CoW layered double hydroxide (CoW-LDH) nanosheet arrays supported on nickel foam (NF) was synthesized through a combined strategy of cobalt metal- organic framework (Co-MOF) template etching and subsequent electrodeposition. The unique synergistic effect in the CoMo alloy and CoW-LDH supported on NF (denoted as CoMo/CoW-LDH/NF) heterostructure not only enhances capability of charge migration but also promotes interfacial charge redistribution. Furthermore, in situ Fourier Transform Infrared Spectroscopy (In-situ FTIR) and density functional theory calculation (DFT) confirm that electron transfer effect at the alloy-LDH interface and reaction intermediates has been optimized, thereby enhancing water molecule adsorption and reducing the energy barrier for water dissociation. As a consequence, requiring only 32 mV overpotential to drive 10 mA cm^-2. Notably, the symmetric dual-electrode cell system based on CoMo/CoW-LDH/NF materials achieves stable operation at just 1.52 V under a current density of 10 mA cm^-2 when operated in 1.0 M KOH solution, surpassing many advanced hydrogen evolution reaction (HER) electrocatalysts. This comprehensive work offers new perspectives for designing alloy/hydroxide integrated electrodes toward efficient hydrogen evolution reactions.