Computational Investigation of Zn Doped Graphitic Carbon Nitride (gcn) Monolayer for CO2 Sensing

In the present work, we have investigated the sensing behavior of pristine graphitic carbon nitride (gCN) and Zn doped gCN monolayer (Zn-gCN) for CO2 gas sensing using DFT calculations. Structural and electronic properties such as adsorption energy, band structure, and density of states (DOS) have been investigated. The calculated adsorption energy of pristine gCN is −1.33 eV. To improve this value, doping is patterned at three sites (i.e., terminal N site, edge N site, and ring N site). The adsorption is maximum at the terminal N site followed by ring N site and edge N site with a value of −8,29 eV, −2.48 eV, and −2.16 eV, respectively. Band gap structure also reflects that the doping at terminal N site is most favorable with a 52.7% shrinking of band gap subsequent to adsorption of CO2 gas compared to pristine gCN. Further, the DOS values also exhibit noticeable change after doping Zn atom at different sites in gCN towards adsorption of CO2 with a maximum increase at the terminal N site. The present study reveals that the sensing performance of the Zn-gCN is significantly enhanced compared to pristine gCN and can be a promising material for CO2 gas sensing.