Elementary photocatalytic chemistry on TiO<sub>2</sub>surfaces

Guo, Qing; Zhou, Chuanyao; Ma, Zhibo; Ren, Zefeng; Fan, Hongjun

doi:10.1039/c5cs00448a

Cited by 291 publications

(215 citation statements)

References 326 publications

Supporting

Mentioning

205

Contrasting

Order By: Relevance

“…The clean TiO 2 R-(110) surface does not reconstruct and exposes alternating rows of Ti 5c and O 2c atoms. [30] However, the LEED pattern of clean TiO 2 R-(011) surface shows a (2×1) reconstruction in the [-100] direction, and the resulting TiO 2 R-(011)-(2×1) surface exposes the Ti 5c atoms at the ridge and valley and the O 2c atoms at the top and bridge. [31] It is noteworthy that the top O 2c atoms on R-(011)-(2×1) surface are arranged in a zig-zag style and severely shade the ridge Ti 5c sites.…”

Section: Methodsmentioning

confidence: 99%

Structural Dependence of Competitive Adsorption of Water and Methanol on TiO₂ Surfaces

et al. 2017

View full text Add to dashboard Cite

Employing TiO 2 anatase (001)-(1×4), rutile (110) and rutile (011)-(2×1) single crystal surfaces, we comprehensively studied the effects of TiO 2 surface structures on the competitive adsorption of water and methanol by means of low energy electron diffraction, thermal desorption spectra and X-ray photoelectron spectroscopy. The relative adsorption strengths of chemisorbed methanol and water vary with the TiO 2 surface structures and the adsorption sites. This leads to TiO 2 surface structure-dependent competitive adsorption of water and methanol. The chemisorption of CH 3 OH on TiO 2 anatase (001)-(1×4) surface is seldom affected by pre-covered water at low coverages but is affected by pre-covered water at high coverages; the chemisorption of CH 3 OH on TiO 2 rutile (110) surface is seldom affected by pre-covered water; and the chemisorption of CH 3 OH on TiO 2 rutile (011)-(2×1) surface is affected by pre-covered water even at low coverages. These results deepen the fundamental understandings of surface chemistry on TiO 2 surfaces.

show abstract

Section: Methodsmentioning

confidence: 99%

Structural Dependence of Competitive Adsorption of Water and Methanol on TiO₂ Surfaces

et al. 2017

View full text Add to dashboard Cite

show abstract

“…[10] However,e nhanced light absorption and/ or suppressed carrier recombination cannot rationally explain the modified reaction schemes in many photocatalytic systems,w hich are more related to the surface delicate OVsubstrate interactions. [11] influencing the kinetics,e nergetics,a nd further the mechanisms of catalytic processes, [7] but an in-depth scenario depicting the interactions between OVsa nd molecular processes of photocatalytic reactions is still unclear. Thus, great efforts have been devoted to clarify the inherent functionality of OVsi np hotocatalysis at the surface molecular level.…”

Section: Introductionmentioning

confidence: 99%

Oxygen Vacancy‐Mediated Photocatalysis of BiOCl: Reactivity, Selectivity, and Perspectives

et al. 2017

Angew Chem Int Ed

908

426

View full text Add to dashboard Cite

Semiconductor photocatalysis is a trustworthy approach to harvest clean solar light for energy conversions, while state-of-the-art catalytic efficiencies are unsatisfactory because of the finite light response and/or recombination of robust charge carriers. Along with the development of modern material characterization techniques and electronic-structure computations, oxygen vacancies (OVs) on the surface of real photocatalysts, even in infinitesimal concentration, are found to play a more decisive role in determining the kinetics, energetics, and mechanisms of photocatalytic reactions. This Review endeavors to clarify the inherent functionality of OVs in photocatalysis at the surface molecular level using 2D BiOCl as the platform. Structure sensitivity of OVs on reactivity and selectivity of photocatalytic reactions is intensely discussed via confining OVs onto prototypical BiOCl surfaces of different structures. The critical understanding of OVs chemistry can help consolidate and advance the fundamental theories of photocatalysis, and also offer new perspectives and guidelines for the rational design of catalysts with satisfactory performance.

show abstract

“…There is, furthermore, a host of interesting phenomena that require a deeper understanding of how nuclear and electronic motions interact with one another during chemical events. In photocatalysis, hot electrons may interact with surface adsorbates to make and break bonds (28). The rate of a reaction on a metal surface is governed by the rate of passage through the transition state of the reaction, which may be influenced by energy dissipation to electronic degrees of freedom (24,29).…”

Section: Significancementioning

confidence: 99%

Unified description of H-atom–induced chemicurrents and inelastic scattering

Kandratsenka

Jiang

Dorenkamp

et al. 2018

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

The Born-Oppenheimer approximation (BOA) provides the foundation for virtually all computational studies of chemical binding and reactivity, and it is the justification for the widely used "balls and springs" picture of molecules. The BOA assumes that nuclei effectively stand still on the timescale of electronic motion, due to their large masses relative to electrons. This implies electrons never change their energy quantum state. When molecules react, atoms must move, meaning that electrons may become excited in violation of the BOA. Such electronic excitation is clearly seen for: (i) Schottky diodes where H adsorption at Ag surfaces produces electrical "chemicurrent;" (ii) Au-based metal-insulator-metal (MIM) devices, where chemicurrents arise from H-H surface recombination; and (iii) Inelastic energy transfer, where H collisions with Au surfaces show H-atom translation excites the metal's electrons. As part of this work, we report isotopically selective hydrogen/deuterium (H/D) translational inelasticity measurements in collisions with Ag and Au. Together, these experiments provide an opportunity to test new theories that simultaneously describe both nuclear and electronic motion, a standing challenge to the field. Here, we show results of a recently developed first-principles theory that quantitatively explains both inelastic scattering experiments that probe nuclear motion and chemicurrent experiments that probe electronic excitation. The theory explains the magnitude of chemicurrents on Ag Schottky diodes and resolves an apparent paradox--chemicurrents exhibit a much larger isotope effect than does H/D inelastic scattering. It also explains why, unlike Ag-based Schottky diodes, Au-based MIM devices are insensitive to H adsorption.M ost theoretical studies of atoms and molecules interacting with metal surfaces are based on the Born-Oppenheimer approximation (BOA) (1). However, a growing number of examples have been found where electronic and nuclear degrees of freedom are strongly coupled in violation of the BOA (2-6). H-atom interactions at metals offer a remarkable opportunity to test non-BOA theories against experiment, since H-adsorptioninduced chemicurrent experiments (7-14) offer a direct measure of electronic excitation and H-atom inelastic scattering experiments (15) directly probe nuclear motion. In chemicurrent experiments, exothermic H interactions like adsorption and recombination produce hot electrons that pass over a potential barrier to be collected. Hence, the magnitude of the chemicurrent is dependent on both the reaction-induced production of hot electrons and the likelihood of transmission over the barrier. To reduce uncertainties associated with barrier transmission, the ratio of hydrogen-and deuterium-induced chemicurrent is often measured--H-induced chemicurrents are typically two to five times larger than those from D atoms (7,(11)(12)(13). H-atom surface scattering experiments yield H-atom translational energy loss distributions. The importance of H-atom translation to electronic exc...

show abstract

Elementary photocatalytic chemistry on TiO₂surfaces

Cited by 291 publications

References 326 publications

Structural Dependence of Competitive Adsorption of Water and Methanol on TiO₂ Surfaces

Structural Dependence of Competitive Adsorption of Water and Methanol on TiO₂ Surfaces

Oxygen Vacancy‐Mediated Photocatalysis of BiOCl: Reactivity, Selectivity, and Perspectives

Unified description of H-atom–induced chemicurrents and inelastic scattering

Contact Info

Product

Resources

About

Elementary photocatalytic chemistry on TiO2surfaces

Cited by 291 publications

References 326 publications

Structural Dependence of Competitive Adsorption of Water and Methanol on TiO2 Surfaces

Structural Dependence of Competitive Adsorption of Water and Methanol on TiO2 Surfaces

Oxygen Vacancy‐Mediated Photocatalysis of BiOCl: Reactivity, Selectivity, and Perspectives

Unified description of H-atom–induced chemicurrents and inelastic scattering

Contact Info

Product

Resources

About

Elementary photocatalytic chemistry on TiO₂surfaces

Structural Dependence of Competitive Adsorption of Water and Methanol on TiO₂ Surfaces

Structural Dependence of Competitive Adsorption of Water and Methanol on TiO₂ Surfaces