Adsorption properties of NO molecules on the hexagonal LaCoO3 (0 0 1) surface: A density functional theory study

Abstract

Six types of adsorption configurations, together with two different adsorption sites for NO adsorption on LaCoO3, were investigated via density functional theory. There were two types of terminal configurations for the LaCoO3 (0 0 1) surface: CoO2- and LaO-terminated. We used the calculated adsorption energy, Mulliken and Hirshfeld charge analysis, the electron density difference and projected density of states analysis methods to determine the electronic and chemical properties of NO adsorbed on LaCoO3. We found that the Co-d and N-p orbitals played primary roles during electron transfer for NO adsorption on CoO2-terminated LaCoO3, and the O-p and N-p orbitals during the electron transfer for NO adsorption on LaO-terminated LaCoO3. Therefore, we assert that the optimal adsorption configuration is Co-NO (N-end of NO on adsorption CoO2-LaCoO3).