Light-driven Low-temperature Dry Reforming of Methane over Carbon-tuned Ni/CeO2 Catalysts

By simply varying the calcination temperature under an Ar atmosphere, the carbon configuration evolved from amorphous to graphitic, with the optimally Ni(750Ar-H)/CeO2 catalyst delivering remarkable H2 and CO production rates of 3546.1 and 5496.4 mmol·g-1 cat.·h-1 at a surface temperature of only 479 °C, attaining a high light-to-fuel efficiency of 41.3%. Structural characterizations showed that graphitic carbon not only narrowed the catalyst band gap and enhanced visible-light absorption but also facilitated charge separation and boosted photothermal conversion.

Mechanistic studies revealed that graphitic carbon promoted oxygen vacancy formation, modulated metal-support interactions and established an efficient surface reaction pathway involving oxygen-containing intermediates. Our findings establish carbon speciation engineering as a powerful strategy to enhance photothermal DRM performance at a low reaction temperature.