Abstract
•The doping enhances the adsorptivity of BN nano-cages to CH2O molecules.•The CH2O adsorption on both of Pristine and doped BN has noticeable changes on their electric conductivity.•Pristine and doped BN nano-cages are promising electrochemical gas sensors for CH2O gas.
The density functional theory (DFT) at B3LYP/6−31 g(d) level of calculations is utilized to examine the effect of doping and co-doping as well as CH2O adsorption on the structural and electronic properties of boron nitride nano-cages. The adsorption properties of CH2O are analyzed in terms of adsorption energies (Eads), charge transfer, the electrostatic potential (ESP), and the density of states (DOS). Our results show that the CH2O is chemically adsorbed via its oxygen atom on the boron and beryllium sites of pristine and doped as well as co-doped boron nitride nano-cages. The Eads was -0.402 eV for the pristine B12N12 nano-cage, while the doping enhances the Eads to be -0.981, -1.219, and -1.138 eV for doped BeB11N12, CB11N12, and co-doped Be2B10N12 nano-cages, respectively. The interaction between the CH2O molecule and the considered nano-cages depends on the ESP around the adsorbing sites. In addition, the interaction between the CH2O molecule and the nano-cages undergoes by the donation-back donation mechanism. The adsorption of the CH2O molecule reduces the HOMO-LUMO gap for the pristine B12N12 by 49 % and for the doped for CB11N12 nano-cage by 22 %, meanwhile, the most decrease is 55 % recorded for the co-doped C2B11N11 nano-cage. Therefore, the adsorption of CH2O affected the electrical conductivity for the pristine and doped as well as co-doped BN nano-cages. The present results proposing that the considered doped boron nitride nano-cages could be a promising material for CH2O gas removal and detection.