title: The adsorption of α-cyanoacrylic acid on anatase TiO2 (101) and (001) surfaces: a density functional theory study.
abstract: The adsorption of α-cyanoacrylic acid (CAA) on anatase TiO2 (101) and (001) surfaces, including adsorption energies, structures, and electronic properties, have been studied by means of density functional theory calculations in connection with ultrasoft pseudopotential and generalized gradient approximation based upon slab models. The most stable structure of CAA on anatase TiO2 (101) surface is the dissociated bidentate configuration where the cyano N and carbonyl O bond with two adjacent surface Ti atoms along [010] direction and the dissociated H binds to the surface bridging O which connects the surface Ti bonded with carbonyl O. While for the adsorption of CAA on (001) surface, the most stable structure is the bidentate configuration through the dissociation of hydroxyl in carboxyl moiety. The O atoms of carboxyl bond with two neighbor surface Ti along [100] direction, and the H from dissociated hydroxyl interacts with surface bridging O, generating OH species. The adsorption energies are estimated to be 1.02 and 3.25 eV for (101) and (001) surfaces, respectively. The analysis of density of states not only suggests the bonds between CAA and TiO2 surfaces are formed but also indicates that CAA adsorptions on TiO2 (101) and (001) surfaces provide feasible mode for photo-induced electron injection through the interface between TiO2 and CAA. This is resulted from that, compared with the contribution of CAA orbitals in valence bands, the conduction bands which are mainly composed of Ti 3d orbitals have remarkable reduction of the component of CAA orbitals.
authors.affiliation: School of Sciences, Lanzhou University of Technology, Lanzhou, Gansu 730050, China.
authors.forename: Jin-Gang
authors.initials: JG
authors.lastname: Ma
authors.affiliation: School of Sciences, Lanzhou University of Technology, Lanzhou, Gansu 730050, China.
authors.forename: Cai-Rong
authors.initials: CR
authors.lastname: Zhang
authors.affiliation: School of Sciences, Lanzhou University of Technology, Lanzhou, Gansu 730050, China.
authors.forename: Ji-Jun
authors.initials: JJ
authors.lastname: Gong
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, Jilin University, Changchun, Jilin 130012, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Yang
authors.affiliation: School of Sciences, Lanzhou University of Technology, Lanzhou, Gansu 730050, China.
authors.forename: Hai-Min
authors.initials: HM
authors.lastname: Zhang
authors.affiliation: School of Sciences, Lanzhou University of Technology, Lanzhou, Gansu 730050, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals, Lanzhou University of Technology, Lanzhou, Gansu 730050, China.
authors.forename: You-Zhi
authors.initials: YZ
authors.lastname: Wu
authors.affiliation: School of Sciences, Lanzhou University of Technology, Lanzhou, Gansu 730050, China.
authors.forename: Yu-Hong
authors.initials: YH
authors.lastname: Chen
authors.affiliation: College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou, Gansu 730070, China.
authors.forename: Hong-Shan
authors.initials: HS
authors.lastname: Chen