First principle study of lithium and phosphorus co-doped graphitic carbon nitride as a nonlinear optical material

Modification of nonlinear optical (NLO) response due to lithium doping and lithium-phosphorus co-doping into the graphitic carbon nitride (g-C3N4) monolayer has been explored by density functional theory (DFT). The energy gap (HOMO-LUMO) is shrunk from 3.89 eV for pristine g-C3N4 to 0.76 and 0.95 eV for lithium doped and lithium-phosphorus co-doped g-C3N4 monolayer respectively. The first hyper-polarizability (beta) is also enhanced from 1.84 x 10(3) au of pristine g-C3N4 to 3.05 x 10(4) and 5.85 x 10(4) au for lithium doped and lithium-phosphorus co-doped g-C3N4 monolayer. An enhancement in the polarizability value is observed due to Li and P doping and co-doping into the g-C3N4 monolayer. The redshift of the absorption band is observed, which narrates the addition or alteration of a donor and acceptor. This article suggests that Li/P co-doped g-C3N4 is a possible NLO material with high-performance.

Automated summary

The effects of lithium doping and lithium-phosphorus co-doping on the nonlinear optical response of the graphitic carbon nitride (g-C3N4) monolayer were investigated, showing enhanced performance with the co-doping of lithium and phosphorus.