Recovering solar fuels from photocatalytic CO2 reduction over W6+-incorporated crystalline g-C3N4 nanorods by synergetic modulation of active centers

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.

Automated summary

In this study, tungsten-doped graphitic carbon nitride (CCN-W) was developed as a catalyst for photocatalytic CO2 conversion. The introduction of W-N-6 as multifunctional active sites significantly enhanced the CO2 reduction rate and selectivity to hydrocarbons. This study provides new insight into modulating CCN photocatalysts for efficient and selective CO2 reduction.