In Situ Carbon Homogeneous Doping on Ultrathin Bismuth Molybdate: A Dual-Purpose Strategy for Efficient Molecular Oxygen Activation

Solar-driven activation of molecular oxygen, which harnesses light to produce reactive oxygen species for the removal of pollutants, is the most green and low-cost approach for environmental remediation. The energy coupling between photons, excitons, and oxygen is the crucial step in this reaction and still remains a challenge. In this study, a dual-purpose strategy for enhanced molecular oxygen activation is established by in situ carbon homogeneous doping on ultrathin Bi2MoO6 nanosheets for the first time. The C-doped ultrathin 2D material exhibits an enlarged bandgap straddling the electro-chemical potential of O-2/center dot O-2 -and H2O/center dot OH, without any attenuation of light absorption. An internal electric field and shortened carrier-transportation distance are also found in the longitude orientation of the nanosheets ([001] axis), leading to a higher density of effective photogenerated carriers localized on the exposed {001} surface. As applied for the nitric oxide removal, the reactive rate over the ultrathin C-doped Bi2MoO6 nanosheets is 4.3 times higher than that over the bulk counterparts as a result of the increasing reactive oxygen species. This new proof-of-concept strategy not only realizes the band structure engineering and charge transportation regulation but also paves a new way to construct highly efficient photocatalytic materials.