An infrared radiation-responsive high-entropy CoCaMgMnAlFe-LDHs for controllable hydrogen generation via NaBH4 hydrolysis: Utilization of steel slag and lithium-ion battery liquid waste

Green processing of steel slag and lithium-ion battery liquid waste poses a global environmental challenge. This study utilizes waste acid (containing Co 2+ , H + and NO 3 – ) and alkali solutions (containing Li + , Na + , OH – and CO 3 2– ) from lithium-ion battery manufacturing to recover metal cations from steel slag (containing Ca 2+ , Mg 2+ , Al 3+ , Fe 3+ , and Mn 2+ ), preparing high-entropy CoCaMgMnAlFe-LDHs catalysts for controllable hydrogen generation via NaBH 4 hydrolysis. The ultimate residue, without any residual hazardous metal cations, enabling safe reintroduction into the natural environment. The presence of Co 2+ endows the CoCaMgMnAlFe-LDHs catalyst with rapid photo-thermal conversion capability, enabling it to rapidly heat up under infrared radiation and efficiently catalyze the reaction of NaBH 4 hydrolysis. The hydrogen generation rate reaches 1.12 mol·h −1 ·g −1 ·W −1 driven by 1050 nm infrared radiation. This study provides a novel approach to the environmentally friendly treatment and high-value utilization of steel slag and lithium-ion battery liquid waste.