Article
Chemistry, Multidisciplinary
Zhi-Wen Wang, Wei-Guang Chen, Da Teng, Jie Zhang, An-Ming Li, Zhao-Han Li, Ya-Nan Tang
Summary: The study shows that external uniaxial strain can significantly reduce the energy barrier for water dissociation on the reduced rutile TiO2(110) surface, especially when the tensile strain is larger than 3%. Additionally, the mechanism of water dissociation changes under certain conditions, indicating the feasibility of engineering water dissociation on this surface using external strain.
Article
Chemistry, Physical
Jessica Kraeuter, Katharina Al-Shamery
Summary: Systematic model investigations have shown that defects, particularly bulk Ti3+ interstitials, play a crucial role in directing reactions of alcohols and aldehydes on rutile Titania. The coadsorption with oxygen can enhance certain reaction paths. In the presence of high defect densities, a stabilisation of acetone on the surface by the formation of a diolate was observed.
Article
Chemistry, Physical
Xiao Tong, Scott P. Price, Jeremy C. Robins, Claron Ridge, Hyun You Kim, Paul Kemper, Horia Metiu, Michael T. Bowers, Steven K. Buratto
Summary: In this study, the adsorption behavior of H2O on a TiO2 surface decorated with VO clusters was investigated using UHV-STM and TPD techniques. The results reveal that the preadsorbed VO clusters can induce the adsorption of H2O molecules at room temperature, forming strings of H2O dimers. This adsorption behavior is reversible and unique to the VO-decorated TiO2 surface.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Moritz Eder, Martin Tschurl, Ueli Heiz
Summary: Heterogeneous photocatalytic systems are often described based on electrochemistry, while neglecting the surface chemistry of the photocatalyst. However, studies on alcohol photoreforming reveal that the electrochemical reaction model is not universally applicable. Therefore, the importance of thermal reactions and the need for systematic studies in different environments for a comprehensive understanding of photocatalysis are highlighted.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Physical
Ji Young Hwang, Gun-hee Moon, Bupmo Kim, Takashi Tachikawa, Tetsuro Majima, Seungwoo Hong, Kangwoo Cho, Wooyul Kim, Wonyong Choi
Summary: The generation of mobile free OH radicals on anatase through a reductive conversion of dissolved O2 is crucial in achieving the mineralization of non-adsorbing substrates, while surface trapped holes lead to the generation of surface-bound OH radicals on both anatase and rutile. Understanding the production pathway of OH radicals in photocatalysis will help optimize their generation for efficient photocatalytic oxidation of pollutants.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2021)
Article
Chemistry, Physical
He Zhou, Xiao Zhang, Jie Zhang, Huizhong Ma, Fan Jin, Yuchen Ma
Summary: A new deep hole-trapping site called 2Ti(6c)-O-br-O-Ti-5c on the rutile TiO2(110) surface has been discovered using many-body Green's function theory, potentially regulating the water photooxidation reaction. Introducing Ti vacancies into rutile to turn it into a p-type conductor may substantially increase the photooxidation efficiency by allowing direct dissociation of H2O at bridging oxygen vacancies.
JOURNAL OF MATERIALS CHEMISTRY A
(2021)
Article
Chemistry, Physical
Manuel Caravaca, Jose Jorge Morales, Jose Abad
Summary: The interaction of nitrogen monoxide with silicon deposited onto a rutile single crystal surface was studied using XPS, UPS, and AES techniques. The results showed oxidation of titanium species and reduction of silicon species, with no detectable adsorbed nitrogen on the surface, suggesting a dissociative adsorption process characterized by a Freundlich isotherm.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Physical
Long Chen, R. Scott Smith, Bruce D. Kay, Zdenek Dohnalek
Summary: The reaction pathways of glycerol on TiO2(110) involve the production of water, hydrogen, and carbon-containing products, with the C-H bond scission channel identified as the primary pathway for hydrogen evolution. The study also suggests that smaller oxygenates are not suitable models for probing the reaction pathways of larger oxygenates on oxide surfaces.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Physical
Guigu Xue, Yuemiao Lai, Fangliang Li, Yinuo Li, Peng Liu, Qing Guo
Summary: This study investigates the photodecomposition of 2-propanol on TiO2 surfaces and reveals the reaction behavior under different temperature and surface coverage conditions. The results indicate that higher temperature and lower 2-propanol surface coverage promote the formation of acetone.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Rulin Sun, Xinlu Liu, Xiao Chen, Li Che, Xueming Yang, Qing Guo
Summary: The formation of ethyl acetate from ethanol photooxidation on a rutile-TiO2 surface was investigated, and it was found that the photon energy has a significant effect on the reaction rate and product formation.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Physical
Fangliang Li, Binli Wang, Xiao Chen, Weiwang Zeng, Rulin Sun, Xinlu Liu, Zefeng Ren, Xueming Yang, Hongjun Fan, Qing Guo
Summary: This study systematically investigated the photochemistry of toluene on a TiO2 catalyst, and found that ultraviolet light can efficiently activate the methyl C-H bond of toluene, forming stable intermediate adsorbed on specific sites until around room temperature. The DFT calculations further revealed that the photocatalytic C-H bond cleavage follows a homolytic manner. These findings provide insights into the photocatalytic functionalization of hydrocarbons on TiO2 catalysts.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Xiufeng Lang, Lei Chen, Yan Zhu, Xiaoxu Liu, Hao Guo, Tingting You, Hongsheng Zhang
Summary: Recent experiments have shown that the efficiency of the oxygen evolution reaction (OER) can be greatly improved in fluorinated TiO2 by forming surface hydrogen bonds, but the mechanism is not yet clear. In this study, dual OER pathways on the fluorinated anatase TiO2(101) surface were investigated using first-principles calculations. It was found that dual H-bonding water molecules play a significant role in facilitating proton transfer and hole trapping in both pathways.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Huili Lu, Zhao-Xu Chen
Summary: Strain-based regulation of catalytic activity has received increasing attention. In this study, adsorption and reactions of AHx on uniformly strained oxide surfaces were investigated. It was found that adsorption energies vary linearly with strain, and expansive strain enhances the adsorption of most adsorbates. C-H/O-H bonds are elongated/shortened with expansive strain, and the adsorption energies of CHx show larger changes compared to OHx and NHx. The results demonstrate the potential of strain engineering for regulating catalytic performance on oxide surfaces.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Huan Fei Wen, Yasuhiro Sugawara, Yan Jun Li
Summary: This study systematically explored the nature of hydrogen atoms on the surface and subsurface of rutile TiO2 using atomic force microscopy, scanning tunneling microscopy, and Kelvin probe force spectroscopy. The behaviors and mechanism of hydrogen atom desorption and transfer were investigated, leading to successful manipulation of the reversible hydrogen atom transfer. The study provides new insights into the nature and manipulation of hydrogen atoms and is useful for designing new catalysts of metal oxides.
SURFACES AND INTERFACES
(2021)
Article
Chemistry, Physical
Takahiro Chiba, Kenji Iida, Shinya Furukawa, Jun-ya Hasegawa
Summary: The study investigates the effect of electric fields on hydrogen or proton transfer through hydroxyl groups on an anatase TiO2 (101) surface using first-principles density functional theory and the modern theory of polarization. Unidirectional surface proton transfer induced by external electric fields at different orientations towards the surface is the focus of this research. The preferred pathway for proton transfer can change depending on the magnitude and direction of the electric field. Detailed analysis reveals that the variation in the energy profile with the electric field is significantly different from the classical electric work of an electric field carrying a point charge. The electric field effect on the energy profile of proton transfer is governed by the rearrangement of the chemical bond network at the interface between water molecules and the surface.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Peng Liu, Guigu Xue, Yuemiao Lai, Yinuo Li, Xiao Chen, Qing Guo
Summary: The surface chemistry of tert-butanol on reduced and oxidized rutile TiO2 surfaces was studied, showing that surface oxidation can enhance iso-C4H8 production and alter reaction channels.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Guigu Xue, Yuemiao Lai, Fangliang Li, Yinuo Li, Peng Liu, Qing Guo
Summary: This study investigates the photodecomposition of 2-propanol on TiO2 surfaces and reveals the reaction behavior under different temperature and surface coverage conditions. The results indicate that higher temperature and lower 2-propanol surface coverage promote the formation of acetone.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Rulin Sun, Xinlu Liu, Xiao Chen, Li Che, Xueming Yang, Qing Guo
Summary: The formation of ethyl acetate from ethanol photooxidation on a rutile-TiO2 surface was investigated, and it was found that the photon energy has a significant effect on the reaction rate and product formation.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Physical
Yuemiao Lai, Zhengtian Pu, Peng Liu, Fangliang Li, Jie Zeng, Xueming Yang, Qing Guo
Summary: The low-temperature C-H bond activation of alkanes is a challenging process in alkane dehydrogenation. This study investigates the oxidative dehydrogenation of ethylbenzene on rutile(R)-TiO2(110) under ultrahighvacuum (UHV) and ambient conditions. The results suggest that the initial step of EB oxidative dehydrogenation differs under UHV and ambient conditions, leading to different product distributions. The findings provide new insights into the fundamental understanding of low-temperature C-H bond activation and can contribute to the development of efficient catalysts for styrene production.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Rulin Sun, Ruimin Wang, Xinlu Liu, Xiao Chen, Li Che, Hongjun Fan, Xueming Yang, Qing Guo
Summary: This study experimentally demonstrated that surface adsorbates not only facilitate the diffusion of H atoms on Pt-clut/R-TiO2(110) surface, but also directly participate in H-2 production, providing new insights into H-2 production with Pt/TiO2 catalysts.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Physical
Fangliang Li, Binli Wang, Xiao Chen, Weiwang Zeng, Rulin Sun, Xinlu Liu, Zefeng Ren, Xueming Yang, Hongjun Fan, Qing Guo
Summary: This study systematically investigated the photochemistry of toluene on a TiO2 catalyst, and found that ultraviolet light can efficiently activate the methyl C-H bond of toluene, forming stable intermediate adsorbed on specific sites until around room temperature. The DFT calculations further revealed that the photocatalytic C-H bond cleavage follows a homolytic manner. These findings provide insights into the photocatalytic functionalization of hydrocarbons on TiO2 catalysts.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Ruijie Hou, Ziling Zeng, Shaoshan Wang, Dengfang Tang, Yuan Tan, Xingkun Chen, Wenshao Yang, Chuanqi Huang, Qing Guo, Yunjie Ding, Xueming Yang
Summary: Oxygen dissociation and surface activation are crucial in heterogeneous catalysis and oxidation processes. In this study, we conducted scanning tunneling microscopy experiments and density functional theory calculations to investigate the oxidation process on a Co(0001) surface. Our results provide atomic-level insights into the oxidation of Co(0001) at different temperatures.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Physical
Yuemiao Lai, Yi Zeng, Xiao Chen, Tao Wang, Xueming Yang, Qing Guo
Summary: This study systematically investigated the photochemistry of ethanol on rutile (R)-TiO2(110) surfaces. It was found that photogenerated holes can induce ethanol decomposition to aldehyde. The initial O-H bond cleavage occurs via a proton-coupled hole transfer process, while the C-H bond cleavage is mediated by holes, leaving two electrons on the surface. The rate of aldehyde formation from the ethoxy group is significantly faster than that from ethanol, suggesting the importance of O-H bond cleavage in ethanol photochemistry.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Yuemiao Lai, Yi Zeng, Fangliang Li, Xiao Chen, Tao Wang, Xueming Yang, Qing Guo
Summary: Photocatalytic ethylbenzene conversion into styrene has been achieved by one hole on rutile (R)-TiO2(100) at 80 K under 257 and 343 nm irradiation. The rate of β-C-H bond cleavage is strongly dependent on hole energy, leading to a much higher yield of styrene formation at 257 nm. This result advances our understanding of low-temperature C-H bond activation and suggests the need for a more sophisticated photocatalysis model.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Physical
Yuemiao Lai, Yi Zeng, Xiao Chen, Tao Wang, Xueming Yang, Qing Guo
Summary: This study systematically investigates the photochemical process of ethanol on rutile (R)-TiO2(110) and finds that one hole can decompose molecular ethanol into aldehyde. The yields of aldehyde from the ethoxy group and ethanol photooxidation on R-TiO2(110) are proportional to the square root of the photon flux, indicating the involvement of photogenerated holes and electrons in bond breaking. The results highlight the importance of O-H bond cleavage in determining the rate of ethanol photochemistry and contribute to a better understanding of TiO2 photocatalysis.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Fangliang Li, Yuemiao Lai, Yi Zeng, Xiao Chen, Tao Wang, Xueming Yang, Qing Guo
Summary: Researchers have successfully obtained highly selective ethene from a model rutile surface using photocatalytic oxidative dehydrogenation of ethane (ODHE) at a high temperature. Ethane reacts with hole-trapped oxidized titanium centers to produce ethyl radicals, which then spontaneously dehydrogenate into ethene. Some of the radicals also rebound with surface sites to produce other products. This study not only advances our understanding of C-H bond activation and low temperature ethane conversion, but also provides new possibilities for achieving high efficiency ODHE under mild conditions.
Article
Chemistry, Multidisciplinary
Fangliang Li, Binli Wang, Xiao Chen, Yuemiao Lai, Tao Wang, Hongjun Fan, Xueming Yang, Qing Guo
Summary: This study successfully converts propane to propene through photocatalysis at low temperature and achieves high selectivity on a model surface. The research results not only advance our understanding of C-H bond activation but also provide a new pathway for highly selective ODHP reactions.