Electron-tailored amorphous nickel-tungsten boride catalysts for high-efficiency photothermal carbon dioxide methanation.

The urgent need for sustainable carbon dioxide (CO2) utilization has driven the development of photothermal catalysis as an efficient strategy for solar-driven CO2 methanation. Herein, we report an amorphous nickel‑tungsten boride (NiWB) catalyst that achieves exceptional conversion of CO2 to methane (CH4) under mild conditions without external heating. The optimized NiWB catalyst exhibits a remarkable CH4 production rate of 19.32 mmol g-1 h-1 with 92.50 % selectivity under full-spectrum illumination (2.0 W cm-2), surpassing most reported Ni-based catalysts. Structural and electronic characterizations reveal that the amorphous framework provides abundant unsaturated active sites, while W incorporation enhances interfacial interactions and modulates the electronic structure of Ni sites, promoting H2 and CO2 activation. In situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFS) analysis confirms a formate-mediated reaction pathway, and kinetic studies demonstrate that photothermal synergy significantly reduces activation energy compared to pure thermal catalysis. Furthermore, the formation of stable WB bonds in amorphous catalyst inhibits crystallization, improving catalyst durability. This work highlights the synergistic advantages of amorphous engineering and electronic modulation in designing efficient photothermal catalysts for sustainable CO2 valorization.