Chemical adsorption of phenacyl-1,2,3-benzotriazole over AMoO4 (010) scheelite surfaces. Structure and electronic properties

Abstract

Ab-initio DFT calculations are presented for the adsorption of phenacyl-1,2,3-benzotriazole on scheelite AMoO4 (A = Ca, Sr and Ba) surfaces. Strong adsorption energy of the organic ligand on the scheelite surface is found. The formation of a bond with covalent character is due to the interaction between the high electronic density of nitrogen and oxygen atoms of the organic molecule, with the empty valence orbitals of the cationic species (A) of the scheelite. This interaction promotes a strongly stabilized interface and it may explain the high reactivity toward nitrogen extrusion reactions in gas-solid experiments of scheelites. The energy band gap of the interface is found to decrease significantly upon molecular adsorption, indicating that this kind of adsorption could increase the conductivity of the interface.