Carbon-monoxide adsorption and dissociation on Nb(110) surface

• Published in: Applied surface science Vol. 328; pp. 641 - 648
• Main Authors: Ning, Hua, Lan, Zhi-Qiang, Guo, Jin, Tan, Ming-Qiu
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.02.2015
• Subjects: Adsorption; Adsorption energy; Approximation; Bridges (structures); Carbon monoxide; Dissociation; Functionals; Mathematical analysis; Nb surface; Niobium; Orbitals; Surface chemistry; Carbon-monoxide; Nb surface; Adsorption energy; Dissociation
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2014.12.088

•CO molecules are easy to dissociate on Nb(110) surface.•CO are adsorbed in part dissociatively and molecularly on Nb(110) surface.•Inclined CO adsorbed on the hollow sites is the most stable adsorption structure.•The σ orbital of CO molecule hybridizes with d orbital of Nb atom apparently.•On top sites, the 2π* orbital of CO molecule interacts with Nb d orbital intensely. The adsorption of CO on the Nb(110) surface has been studied by using the density-functional theory with total-energy calculations. In addition to the adsorption geometries, the vibrational properties, surface electronic structures, and dissociation pathways of CO adsorption on the Nb(110) surface have been investigated. The Perdew–Burke–Ernzerhof (PBE), meta generalized gradient approximation (meta-GGA), and hybrid functional (HSE06) functionals were applied to discuss the site preference in the Nb-p(1×1) surface. Results showed that the inclined CO adsorbed on the hollow sites is the most stable structure from total-energies using different functionals. Furthermore, at lower coverage, CO molecules adsorbed on the Nb(110)-p(2×2) surface are easy to dissociate to forming the atomic adsorption from NBE calculations. PDOS showed that in the cases of CO adsorbed on hollow and bridge sites, the σ orbitals of CO molecule hybridize with d orbitals of Nb atom apparently, while on top sites, the 2π* orbitals of CO molecule interact with Nb d orbitals intensely.