First-principles calculations of molecular adsorption on the surface of two-dimensional BCOH

Abstract

• BCOH has good dynamic and thermal stability and is an indirect semiconductor. • Different molecular adsorptions on the surface of BCOH are theoretically studied. • When NO or NO 2 is adsorbed on BCOH, a semiconductor-to-metal transition occurs. A two-dimensional structure by the dehydration reaction of 1,3,5-benzenetriboronic acid (shorted as BCOH) is investigated. BCOH is dynamically and thermally stable. It is an indirect semiconductor possessing a band gap of 3.83 eV. The adsorption behavior of CO, CO 2 , H 2 , H 2 O, NH 3 , NO and NO 2 on BCOH are mainly investigated. The results show that most of the gas molecules prefer to adsorb at the interval sites (I1 or I3). The adsorption energies of NO and NO 2 are lower than the other molecules, revealing that NO and NO 2 have better adsorption affinity on BCOH. Except NO and NO 2 , the band gaps are slightly changed with the molecular adsorption. When NO or NO 2 is adsorbed on BCOH, the band gap becomes zero, revealing that a semiconductor-to-metal transition occurs and the conductivity is improved a lot. Thus, BCOH may provide promising potentials for the detection of nitrogen oxides (NO or NO 2 ).