Abstract
Graphitic carbon nitride (g-C3N4) is promising for photocatalytic conversion of greenhouse gas CO2 into valuable solar fuels. Crystalline g-C3N4 (CCN) attracts great attention, nevertheless, the CO2 reduction efficiency and selectivity are still dissatisfying, due to the lack of suitable active sites. In this study, tungsten doped CCN (CCN-W) is constructed by forming W-N6 bonding at the cavity sites of adjacent heptazine units. Significantly, relative to CCN, the full-spectrum CO2 reduction rate (11.91 mu mol g(-1) h(-1)) on CCN-W is increased by > 5 times, meanwhile, the photoelectron selectivity to hydrocarbons (CH4 and C2H4) approaching 83% is increased by > 2 times. The W6+-doping introduced W-N-6 as multifunctional active sites enrich both the photoelectrons and CO2 molecules, and catalyze their selective conversion into hydrocarbons by reducing reaction barrier and moder-ately stabilizing CO intermediates. This study will offer new insight into modulating the CCN photocatalysts with multifunctional active sites for efficient and selective photocatalytic CO2 reduction.
NSTL
Elsevier