Photocatalytic syngas production from bio-derived glycerol and water on AuIn-decorated GaN nanowires supported by Si wafer

Green syngas production from Earth-abundant and renewable resources is a viable means to achieve carbon neutrality. However, this critical path to realize net-zero carbon dioxide emissions has remained extremely challenging. In this work, by coupling GaN nanowires (NWs) with dual gold-indium nanoparticles (NPs) onto wafer-scale silicon, a novel and well-developed photocatalytic architecture of AuIn NPs/GaN NWs/Si has been assembled for the first time to produce syngas with bio-derived glycerol, water, and concentrated light as the only inputs. By correlative experimental and theoretical investigations, the AuIn/GaN interface is found to be synergistically favorable for dehydrogenating the edge functional group of -CH 2 OH of the glycerol skeleton, followed by the cleavage of the inert C(sp 3 )-C(sp 3 ) bond toward an ethylene glycol-based intermediate with a greatly reduced reaction energy barrier in glycerol solution. Owing to the exceptional optoelectronic and catalytic properties, syngas yields a benchmarking activity of 149.3 mmol g −1 h −1 under mild conditions without an extra energy input other than light. The H 2 /CO ratio can be broadly tailored from 19.3 to 0.9, thus favoring various downstream products. Water plays a vital role in the highly efficient formation of syngas by providing active species e.g. , hydroxyl radicals through photocatalysis. Owing to the widespread distribution of biomass, water, and sunlight, and the industrially available semiconductor platform, this work promises to efficiently and selectively produce next-generation distributed syngas. Green syngas production from Earth-abundant and renewable resources is a viable means to achieve carbon neutrality.