Au/MoS₂ tips as auxiliary rate aligners for the photocatalytic generation of syngas with a tunable composition

Synthesis gas (syngas), with a wide range of molar ratios of CO and H₂ from 0.3 to 4, can serve as an important feedstock in the petroleum industry for the production of various synfuels; however, it remains a major challenge to tune the composition over such a wide range of ratios. Here, we demonstrate the photocatalytic production of syngas with tunable H₂/CO molar ratios via rationally designed Au/MoS₂ symmetrically tipped CdS nanowires (AMTCs), in which MoS₂ and Au serve as cocatalysts for the hydrogen evolution reaction (HER) and CO₂ reduction reaction (CO₂RR), respectively. The competing reactions are controlled and aligned through the selective decoration of size-controlled (1–50 nm) Au nanoparticles on MoS₂ by controlling the charge transfer kinetics during photodeposition. Finally, the widest range of H₂/CO ratios in syngas reported to date, ranging from 0.35 to 3.6, is realized, indicating that this is a potentially efficient approach for solar-to-syngas production by using rationally designed nanostructures.