Chemisorption of O2 on Ag(110)

First-principles studies of the oxygen adsorption on unreconstructed and reconstructed Ni(110) surfaces

“…This results are consistent with experiment [8], in which unreconstructed ðn  1Þ-O (n = 2, 3) structures were found to coexist with reconstructed ðn  1Þ-O structure at low oxygen exposure and oxygen atoms located in the short-bridge sites. This is different from the case of O/Cu(1 1 0) [41] and O/Ag(1 1 0) [42]. The DFT calculations about oxygen on Cu(1 1 0) predicted that the most stable site was the LB sites for full and half coverage, whereas the hollow site was found to be the most favorable site in the case of O/Ag(1 1 0).…”

Chemistry at molecular junctions: Rotation and dissociation of O2 on the Ag(110) surface induced by a scanning tunneling microscope

“…A broad range of experiments on O 2 /Ag(110) over the years, 26 including, electron energy loss spectroscopy (EELS), [27][28][29][30] temperature programmed desorption (TPD), 28,30,31 ultraviolet photoemisson, 32,33 electron stimulated desorption ion angular distributions (ESDIAD), 34 near-edge x-ray absorption fine structure studies (NEXAFS), 35, 36 molecular beam studies, 29,37 and STM 24,25,38,39 have determined that (a) O 2 undergoes physisorption at surface temperature, T s < 40 K, chemisorption at 40 K < T s < 175 K, and dissociation at T s > 175 K, (b) O 2 adsorbs parallel to the surface on the fourfold hollow (FFH) site along either the (001) or (110) direction, and (c) the vibrational frequency of chemisorbed O 2 is significantly reduced from its gas-phase value of 1580 cm −1 to 640 cm −1 indicating strong surface-to-molecule electron transfer. Density functional theory (DFT) calculations by Gravil et al [40][41][42] studied the underlying electronic structure of the O 2 -surface bond and confirmed the chemisorption geometry observed by experiment. Molecular dynamics simulations by Pazzi et al 43,44 investigated the incidence-energydependent and coverage-dependent sticking probabilities of O 2 on Ag(110), and more recently, DFT calculations by Olsson et al, 45 Alducin et al, 46 and Monturet et al 47 studied the STM images and IETS of O 2 on Ag(110).…”

Continuum and Quantum-Chemical Modeling of Oxygen Reduction on the Cathode in a Solid Oxide Fuel Cell

“…Therefore, the variation of reduction barriers at 2PBs can be determined. For example, on Ag surfaces, dissociation barriers are 0.85-1.06 eV and 0.60-0.70 eV in Ag (111) [116,158] and (110) [116,149,150] surface orientations, respectively, while those are 0.70-1.00 eV and 0.70-0.90 eV in Pt (111) [135,136,141,146] and (211) [141,146] surfaces, respectively. Based on these calculations, it can be summarized that the reduction barriers at metal electrodes (2PBs) are higher than 0.60 eV and the barrier changes induced by the surface morphology are less than 0.15 eV.…”

“…Compared to the oxygen interactions with metal-oxide surfaces, theoretical studies on metallic surfaces (2PBs) have been more extensively reported as summarized in [101]. In order to examine the oxygen reduction reaction at the 2PBs in SOFC applications, Pt [133][134][135][136][137][138][139][140][141][142][143][144][145][146][147] and Ag [116,[148][149][150][151][152][153][154][155][156][157][158] cathode materials will be discussed. It is well known that different surface morphologies, subsurface elements and surface charges induce d-band shifting of the metal electrodes and change O 2 dissociation barriers in different surface orientations [130].…”