Facile Immersing Synthesis of Pt Single Atoms Supported on Sulfide for Bifunctional toward Seawater Electrolysis

Seawater electrolysis for hydrogen production represents a substantial opportunity to curtail production expenditures and exhibits considerable potential for various industrial applications. Platinum-based precious metals exhibit excellent activity for water electrolysis. However, their limited reserves and high costs impede their widespread use on a large scale. Single-atom catalysts, characterized by low loading and high utilization efficiency, represent a viable alternative, and the development of simple synthesis methods can facilitate their practical application. In this work, we report the facile synthesis of a single-atom Pt-loaded NiCoFeS_x (Pt@NiCoFeS_x) bifunctional catalytic electrode using a simple impregnation method on a nickel foam substrate. The resulting electrode exhibits low overpotentials for both HER (60 mV@10 mA cm⁻²) and OER (201 mV@10 mA cm⁻²) in alkaline seawater electrolytes. When incorporated into a seawater electrolyzer, this electrode achieves a direct current energy consumption of only 4.18 kWh/Nm³H₂ over a 100 h test period with negligible decay. These findings demonstrate the potential of our approach for industrial-scale seawater electrolysis.