Platinum nickel alloy-MXene catalyst with inverse opal structure for enhanced hydrogen evolution in both acidic and alkaline solutions

The development of an efficient Pt-based electrocatalyst in acidic and alkaline electrolytes is of great significance to the field of electrocatalytic hydrogen evolution. Herein, we report a strategy for in situ growth of Pt₃Ni truncated octahedrons on Ti₃C₂T_x nanosheets and then obtain an ordered porous catalyst via a template method. Meanwhile, we use the finite element calculation to clarify the relationship between the component structure and performance and find that the performance of the spherical shell microstructure catalyst is higher than that of the disc structure catalyst, which is also verified by experiments. The experimental analysis shows that the ordered porous catalyst is conducive to enhancing electrocatalytic hydrogen evolution activity in acidic and alkaline electrolytes. In an acidic solution, the overpotential is 25 mV (10 mA·cm⁻²), and the Tafel slope is 22.86 mV·dec⁻¹. In an alkaline solution, the overpotential is 44.1 mV (10 mA·cm⁻²), and the Tafel slope is 39.06 mV·dec⁻¹. The synergistic coupling between Ti₃C₂T_x and Pt₃Ni nanoparticles improves the stability of the catalyst. The in situ growth strategy and design of microstructure with its correlation with catalytic performance represent critical steps toward the rational synthesis of catalysts with excellent catalytic activity.