Ultraviolet-visible-near-infrared Irradiation Responsive High-entropy Layered Double Hydroxides for On-demand Hydrogen Evolution Reaction via Sodium Borohydride Hydrolysis

Sodium borohydride holds great promise as a stable hydrogen-rich carrier. However, hydrogen evolution reaction (HER) via NaBH 4 hydrolysis typically requires relatively high solution temperatures. Due to the elevated specific heat capacity of water, controlling the reaction temperature is not feasible, which leads to an uncontrollable hydrogen production rate and poses safety risks. This work proposes an innovative strategy for controllable photo-thermal synergistic catalysis by inducing the coexistence of photo-responsive and photo-thermal conversion cations within the framework of the catalyst through the high-entropy effect. A series of high-entropy Co 6- x Ni x FeAl 1- y Ga y -layered double hydroxides (CoNiFeAlGa-LDHs) were synthesized by hydrothermal method, exhibiting ultrafast photo-responsive catalytic capacity across a broad spectral range from 200 to 1500 nm. By controlling the illumination, CoNiFeAlGa-LDHs demonstrated exceptional on-demand HER capacity via NaBH 4 hydrolysis. Notably, the H 2 evolution rate of high-entropy Co 3 Ni 3 FeAl 0.5 Ga 0.5 -LDHs reaches 13.60 mol·g -1 ·h -1 and 2.76 mol·g -1 ·h -1 under full-spectrum and near-infrared irradiation, respectively. This surpasses the efficiency of most Co-based catalysts ever reported, presenting a novel approach to achieve for on-demand HER via NaBH 4 hydrolysis.