Photocatalytic oxidation of methane to methanol by tungsten trioxide-supported atomic gold at room temperature

Atomic-scale metals as active center have been widely investigated for efficient photocatalysis. Understanding the specific electronic structure of atomic-scale center is of profound fundamental importance for superior catalytic performance. Here, we report an atomically dispersed gold on tungsten trioxide (Au1/WO3) catalyst for photocatalytic oxidation of methane toward value-added methanol. The Au1 species reveal a specific tip-enhanced local electrons field which favors the C-H dehydrogenation of methane and thus form methanol (up to 589 µmol g−1 h−1). Both experimental and theoretical results demonstrate such tip-enhanced effect enhance the catalytic activity of methane oxidation. The theoretical calculations further reveal a lower adsorption energy of product methanol on Au1, in contrast to Au particles, which suppresses the overoxidation of methanol, and thus promotes its selectivity. Establishing the relationship between electronic density and catalytic activity may create a platform for designing efficient atomic-scale catalysts for C1 catalysis and green chemistry.