Single Atom (Pd/Pt) Supported on Graphitic Carbon Nitride as an Efficient Photocatalyst for Visible-Light Reduction of Carbon Dioxide

Reducing carbon dioxide (CO 2 ) to hydrocarbon fuel with solar energy is significant for high-density solar energy storage and carbon balance.In this work, single palladium/platinum (Pd/Pt) atoms supported on graphitic carbon nitride (g-C 3 N 4 ), i.e.Pd/g-C 3 N 4 and Pt/g-C 3 N 4 , acting as photocatalysts for CO 2 reduction were investigated by density function theory (DFT) calculations for the first time.During CO 2 reduction, the individual metal atoms function as the active sites, while g-C 3 N 4 provides the source of hydrogen (H*) from hydrogen evolution reaction.The complete, as-designed photocatalysts exhibit excellent activity in CO 2 reduction.HCOOH is the preferred product of CO 2 reduction on the Pd/g-C 3 N 4 catalyst with a rate-determining barrier of 0.66 eV, while the Pt/g-C 3 N 4 catalyst prefers to reduce CO 2 to CH 4 with a rate-determining barrier of 1.16 eV.In addition, depositing atom catalysts on g-C 3 N 4 significantly enhances the visible light absorption, rendering them ideal for visible light reduction of CO 2 .Our findings open a new avenue of CO 2 reduction for renewable energy supply.