A DFT study on the functionalization of a BN nanosheet with PCsingle bondX, (PC = phenyl carbamate, X = OCH3, CH3, NH2, NO2 and CN)

By using density functional theory calculations, we investigated the chemical functionalization of a BN nanosheet with different organo-azo derivatives including PCsingle bondX, (PC = phenyl carbamate, X = OCH3, CH3, NH2, NO2 and CN) in terms of geometric, energetic, and electronic properties. Reaction energies have been calculated to be in the range of 0.19 to 0.35 eV which is augmented by increasing the electron withdrawing characteristic of the functional groups so that the relative magnitude order is single bondNO2 > single bondCN > single bondOCH3 > single bondCH3 > single bondNH2. The chemical functionalization leads to a decrease in HOMO/LUMO energy gap of BN sheet especially after adsorption of PCsingle bondNO2 by about 1.88 eV. Conduction level and Fermi level of the BN sheet are shifted to lower energies upon the functionalization of the sheet with PCsingle bondNO2 and PCsingle bondCN, thus, it leads to an increment in work function of the sheet, impeding the field electron emission.