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Updated: Jul 9, 2026
09:40
Measurement and Analysis of Atomic Hydrogen and Diatomic Molecular AlO, C2, CN, and TiO Spectra Following Laser-induced Optical Breakdown
Published on: February 14, 2014
Excess charge driven dissociative hydrogen adsorption on Ti2O4.
Xiaowei Song1, Matias R Fagiani1, Sreekanta Debnath1
1Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstrasse 2, D-04103 Leipzig, Germany. knut.asmis@uni-leipzig.de and Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany.
Physical Chemistry Chemical Physics : PCCP
|August 19, 2017
Summary
The negative charge on Ti2O4- significantly lowers the D2 dissociation barrier, enabling quasi barrier-free adsorption. This mechanism models oxygen vacancies on titania surfaces for catalysis research.
Area of Science:
- Surface Science
- Catalysis
- Computational Chemistry
Background:
- Understanding oxygen vacancies on titania surfaces is crucial for catalytic applications.
- Dissociative adsorption of molecules like D2 provides insights into surface reactivity.
- Ti2O4- serves as a model system for studying these phenomena.
Purpose of the Study:
- To elucidate the mechanism of dissociative D2 adsorption on the Ti2O4- cluster.
- To investigate the role of excess negative charge in the adsorption process.
- To model oxygen vacancy behavior on titania surfaces.
Main Methods:
- Infrared photodissociation spectroscopy.
- Density functional theory (DFT) calculations.
- Artificial Force Induced Reaction (AFIR) method.
Main Results:
- Ti2O4- readily reacts with D2 at 16 K, forming a stable (DO-Ti-(O)2-Ti(D)-O)- structure.
- The reaction proceeds quasi barrier-free via intermediates, involving heterolytic D2 bond cleavage and D-atom migration.
- Excess negative charge on Ti2O4- substantially lowers the D2 dissociation barrier compared to neutral Ti2O4.
Conclusions:
- The excess negative charge in Ti2O4- is key to facilitating D2 dissociation.
- The study provides a detailed mechanistic understanding of D2 adsorption on a titania-like model system.
- Findings are relevant for designing advanced catalytic materials with controlled oxygen vacancies.
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