Enabling the life-cycle consideration and approach for the design of efficient water splitting catalyst via engineering amorphous precursor

Electrocatalytic water splitting is one of the ultimate solutions to generate hydrogen. Like the Li-ion battery industry, a big catch is often neglected regarding the environmentally-friendly preparation of electrode materials and the treatment of end-of-life electrode. The potential release of hazards poses a new challenge to sustainable development. Herein we designed a series of amorphous Co_xM_1-xWO_y (M = Fe, Ni, Cu and Zn) OER catalyst that enabled the implementation of a life-cycle consideration. The metal dissolution from the catalyst in service was controlled in an ``activation'' step. The spent catalysts and the discharged metal ions from the synthesis and activation steps were recycled with high efficiency to make new batches of catalysts, delivering equally excellent OER activity of 253 mV overpotential at 10 mA cm<sup>-2</sup>. This materials design and synthesis consideration throughout the life cycle might inspire other scientists to develop ``greener'' yet high-performance materials for sustainable applications.