Interfacial Adsorption and Electron Properties of Water Molecule/Cluster on Anatase TiO₂(101) Surface: Raman and DFT Investigation

Abstract

The hydrogen bond network reconstruction at the titanium/water interface was monitored by Raman spectroscopy. In addition, the adsorption properties and the surface electron properties of hydrogen bond cluster (HBC) configurations were analyzed using adsorption energy, work function, Mulliken charge population, and density of states (DOS) by the first-principles method based on density functional theory (DFT). Our results show that the hydrogen bond network of the aqueous solution is reconstructed under the interaction with the anatase TiO2(101) surface with the transformation of the chain and free hydrogen bonds to complex hydrogen bonds. The adsorption energy of a single water molecule and HBC on the anatase TiO2(101) surface are the lowest with the 1-DD-h (−0.851 eV) and 3-D-h-DDA (−1.048 eV) configurations, respectively. Over the long term, artificially regulating the structure of the HBC might be an effective and general way to slow down the metal anodic reaction without surface modification. Furthermore, the surface charge concentrates on the bridging oxygen atom, which will be the active site of the interface reaction. It is helpful to clarify the anodic corrosion reaction mechanism of the titanium spontaneous oxide film/water interface.

Spectroscopic and Simulation Insights into the Corrosion Mechanism of Sulfite on Titanium

“…Compared with the work function of the bare surface (7.35 eV), the work function of the most unstable Ti2O b -parallel configuration decreased by 0.02 eV and the most stable TiO b -parallel configuration decreased by 0.72 eV. In our previous research, ,,, the five adsorption types of HB structures and corresponding surface work functions on anatase TiO 2 (101) have been investigated. The order of promoting anodic solubility is DA > DDA > DDAA > free > DAA.…”

“…As shown in Figure b, the SO 3 2‑ adsorption behavior at the anatase TiO 2 (101) surface is simulated by the CASTEP software . The electronic exchange relies on the GGA-PBE functional . There are 5.0 × 10 –6 eV electronegativity iterations and 0.01 eV·Å –1 forces on each atom in this model.…”

“…21 The electronic exchange relies on the GGA-PBE functional. 22 There are 5.0 × 10 −6 eV electronegativity iterations and 0.01 eV•Å −1 forces on each atom in this model. For the Ti 3d orbitals, the Hubbard + U parameter is set to 4.2 eV, and for the O 2p orbitals, it is set to 4.0 eV.…”

Theoretical Exploration of Peculiar Sandwich-Type Clusters Formed by the Coordination of E92– (E = Si, Ge, Sn) Zintl Clusters: Structural Properties, Active Sites, and Hydrogen Storage

“…Moreover, the bond order analysis can prove the previous bond length conclusion: as the bond length increases, the bond order decreases. For 1−3, the bond orders (η 6 -E(ii)-E(i) and E(ii)-Pd) decrease gradually because there are strong chemical bonds when E (E = Si, Ge, Sn) changes from Si to Sn, whereas the Pd−P bond orders gradually increase.…”

“…In 2020, Sun et al reported the synthesis and characterization of an anionic sandwich substance, {(Ge 9 ) 2 [η 6 -Ge-(PdPPh 3 ) 3 ]} 4− . 1 This experimental observation of {(Ge 9 ) 2 [η 6 -Ge(PdPPh 3 ) 3 ]} 4− , the first of its kind, is predicted to promote an upsurge in the research of this system and systems similar to it. We believe that comprehensively characterizing all aspects of these compounds is important to facilitate the understanding of these systems and ultimately help promote research, which will lead to the design of various valuable derivatives.…”