Light-Induced In Situ Formation of a Nonmetallic Plasmonic MoS/MoO Heterostructure with Efficient Charge Transfer for CO Reduction and SERS Detection.

Low-cost and abundant reserved nonmetallic plasmonic materials have been regarded as a promising substitute of noble metals for photocatalysis and surface-enhanced Raman scattering (SERS). In this paper, a MoS/MoO heterostructure was synthesized by light-induced in situ partial oxidation of MoS nanosheets, exhibiting strong surface plasmon resonance (SPR) in a vis-near-infrared (NIR) region. Continuously plasmon-induced hot electrons boost CO reduction to CO due to efficient photoelectron injection from MoS to MoO. Under UV-vis-NIR irradiation, the CO generation rate reached 32.4 μmol g h with a selectivity of 94.1%, which was much higher than that of single MoS or MoO. Furthermore, the plasmonic MoS/MoO heterostructure exhibits superior SERS performance for sensitive rhodamine 6G detection (10 M) with an enhancement factor of ∼10 because of the synergy between SPR and charge transfer effect. This work provides one novel mild synthetization of a plasmonic heterostructure and demonstrates its potential in plasmon-enhanced CO reduction and SERS detection.