Influence of Pt and P doping on the performance of g-C3N4 monolayer

ABSTRACT

Density functional theory (DFT) is used to find out the effect of platinum and phosphorus doping (as individuals and together) on the structural, electronic as well as optical performance of heptazine based graphitic carbon nitride (g-C₃N₄) monolayer. The calculated bandgap value for the pristine g-C₃N₄ is 1.2 eV. In the case of Pt doping delocalization of the frontier molecular orbitals (MO) are not adequate, but P doping as individual and together with Pt results in strong delocalization of frontier MOs. Pt and P co-doping provides two new paths, for the relocation of photogenerated charge carriers between adjacent heptazine units.

Furthermore, there is a magnified optical absorption in the ultraviolet as well as the infrared region and improved electronic movement in co-doped g-C₃N₄. Optical conductivity is enhanced by approximately 40% at 200 nm after the co-doping. A decrease in the work function value is also observed in doped g-C₃N₄ with the minimum amount for Pt and P co-doping. Thus Pt/P co-doping process may be considered as a tool to upgrade the photocatalytic performance of g-C₃N₄ monolayer.

KEYWORDS:

• DFT
• platinum
• phosphorus
• co-doping
• g-C₃N₄
• absorption
• ultraviolet
• infrared
• conductivity