Metals (Cu, Ag, Au) encapsulated gallium nitride nanotubes (GaNNTs) as sensors for hexabromodiphenyl ether (HBDE) emerging organic pollutant: A computational study

Abstract

This study is aimed at investigating the potential of transition metals (Cu, Ag, Au) doped gallium nitride nanotubes (GaNNTs) as sensor materials for the enhanced detection of hexabromodiphenyl ether (HBDE) an emerging organic pollutant that has been linked to several health problems, including developmental and neurological disorders, hormonal imbalances, and cancer. Using the density functional theory (DFT) method at the B3LYP-D3(BJ)/def2SVP level of theory, the potential of pristine and metal (Ag, Au, and Cu) doped gallium nitride (GaNNT) nanotube to sense and detect HBDE was evaluated. The interaction of HBDE on the surface was evaluated at two sites, the bromine (Br) and oxygen (O) sites to evaluate the best conformation adsorption. The results showed that the Br site was the preferred sites of adsorption with binding energies of −43.926 kcal/mol, −43.926 kcal/mol, −43.926 kcal/mol and −31.376 kcal/mol for HBDE_Br_Ag@GaNNT, HBDE_Br_Au@GaNNT, HBDE_Br_Cu@GaNNT and HBDE_Br_@GaNNT respectively. The mechanism of surface adsorption was found to be chemisorption and doping of GaNNT surface with metals was found to enhance the conductivity and sensitivity of the surface towards the adsorbent. The result of the thermodynamic assay also affirmed the spontaneous and favorable nature of the surface and adsorbent. Overall, the various analysis considered so far, points that pristine and metal functionalized GaNNT could be used as potential materials to sense HBDE.