NEW JOURNAL OF CHEMISTRY
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2020
·Vol. 44
·期 45
·19924-19932
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IF 3.288
Yifan Liu,Zirui Yu,Shanshan Guo,Lulu Yao,Runze Sun,Xiuying Huang,Weirong Zhao
Transition metal (M = Cu, Fe and Ni) modified TiO2 nanosheets were synthesized via a microwave assisted hydrothermal method. The as-fabricated catalysts were characterized using X-ray diffraction (XRD), electron microscopy, X-ray photoelectron spectroscopy (XPS), nitrogen adsorption–desorption, UV-vis diffuse reflectance spectroscopy (DRS), photoluminescence emission (PL), transient photocurrent–time curves and electrochemical impedance spectroscopy (EIS). The results indicated that the loading of transition metals did not influence the crystal structure and morphology of anatase TiO2, while the specific surface area, the absorption in the visible region and the charge transfer were enhanced. In addition, photocatalytic nitrogen fixation over the transition metal modified TiO2 nanosheets was also evaluated. Under the irradiation of simulated sunlight, transition metal modified TiO2 exhibited better photocatalytic performance and stability than pristine TiO2. Among these samples, Cu/TiO2 with the optimal mass content of 1.0% achieved the best NH4+ generation performance and the evolution rate reached 6.78 mmol g−1 h−1 with the relative standard deviation of 2.33%. Furthermore, a plausible mechanism coupled with interfacial charge transfer (IFCT) over Cu modified TiO2 nanosheets was proposed in our present study.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2019
·
IF 3.45
Guiliang Zhu,Sheng Feng,Jianying Chao,Wei Zheng,Cong Shao
A simple one-pot method was employed to synthesize C-dots modified TiO 2 nanosheets (NS)/UiO-66-NH 2 for enhancing photocatalytic activity. Anatase TiO 2 NS and UiO-66-NH 2 were closely combined and C-dots were well modified on their surfaces. The photocatalytic activities of catalysts were assessed through photodegrading ketoprofen (10 mg/L) under visible light. C-dots/TiO 2 NS/UiO-66-NH 2 degraded 90% of ketoprofen in 80 min, and owned the higher kinetic rate than TiO 2 NS (24 times) or TiO 2 NS/UiO-66-NH 2 (2.1 times). The results indicated that C-dots/TiO 2 NS/UiO-66-NH 2 exhibited the most superb visible-light photocatalytic activity. Besides, C-dots/TiO 2 NS/UiO-66-NH 2 showed good stability and reusability in four runs of degrading ketoprofen. The improved photocatalytic performance was caused by the heterostructure of TiO 2 NS and UiO-66-NH 2 and photoelectrical performance of C-dots, effectively absorbing visible light and promoting photoelectrons transfer.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
APPLIED SURFACE SCIENCE
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2022
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IF 7.392
Qi Zhao,Ye Yuan,Luyan Zhang,Liang Qiao,Cheng Ding,Kangshun Wang,Hongpeng Li,Jun Ma,Panpan Wang,Tianming Chen,Feihong Wang
Nonmetal doping is widely used in the modification of titanium dioxides (TiO 2 ) for photocatalytic applications. As a typical two-dimensional layered nanomaterial, the excellent physical and chemical properties of MXene materials have been the focus of current research. In this study, carbon and fluorine co-doped MXene derived TiO 2 nanosheets (labelled as C-F-TiO 2 ) were successfully synthesized and used as catalysts for degrading 2,4,6-trichlorophenol (2,4,6-TCP) under UV light irradiation. The C-F-TiO 2 with ultrathin nanosheet structure enhanced light absorption range and decreased the bandgaps. The degradation efficiency of 2,4,6-TCP by C-F-TiO 2 was over 99 % in 90 min, and the degradation rate was more than twice that of commercial TiO 2 . The degradation rate still remained about 90 % in 90 min after five cycles. The results of quenching experiments and electron spin resonance (ESR) illustrated that more reactive oxygen species (ROS) were generated in the C-F-TiO 2 /UV system, which was 1.5 times that of commercial pure TiO 2 , and • O 2 – was the dominant ROS for 2,4,6-TCP degradation. This study provided insight to utilize physicochemical characteristics of MXene to synthesize non-metal co-doped TiO 2 nanosheet as a catalyst, exhibiting excellent reactivity in the potential application for organic pollutant degradation.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
Materials Today Chemistry
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2022
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IF 7.613
Qiuyan Tan,Kaining Li,Qing Li,Yaobin Ding,Jiajie Fan,Zhihua Xu,Kangle Lv
TiO 2 nanosheet is a fruitful paradigm for a wide variety of photocatalytic applications due to its characteristics of high photoactivity, robust stability, and environmental friendliness. However, its pragmatic utilization for visible light photocatalytic energy conversion still remains challenging owing to the wide bandgap. Herein, a 2D/3D TiO 2 /ZnIn 2 S 4 nanostructure was purposively constructed via a microwave-assisted synthesis, with ZnIn 2 S 4 functioned as a photosensitizer to overcome the lack of visible light response capacity for TiO 2 . The optimal TiO 2 /ZnIn 2 S 4 sample exhibits an excellent photocatalytic H 2 evolution activity with a rate of 1167.38 μmol/g/h under visible light illumination, far beyond that of pristine TiO 2 nanosheet (6.78 μmol/g/h) and ZnIn 2 S 4 (378.51 μmol/g/h). The enhanced photocatalytic performance can be attributed to synergy effects of the extended visible light response, compatible band alignment, and fast charge carrier separation. The in situ irradiated X-ray photoelectron spectroscopy (XPS) was used to systematically study the transfer behavior of photo-induced electrons; the results highlighted that the flow direction of photoexcited charges is from ZnIn 2 S 4 to TiO 2 nanosheets due to the strong interfacial contact. Then both ZnIn 2 S 4 and TiO 2 nanosheets can act as the active sites for proton reduction, which therefore boosts the hydrogen production under visible irradiation. This work opens a new venue for the development of flexible photosensitization systems for solar-driven energy conversion.
研究领域:
材料科学
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能源转换
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环境科学
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DOI
高影响因子
ACS Applied Nano Materials
·
2023
·
IF 5.9
Xiaohui Sun,Xueying Zhao,Xuyang Zhang,Guohua Wu,Xianhui Rong,Xiangwei Wang
Ti3C2Tx MXene is a potential microwave absorption material due to its unique physical and chemical properties. However, the impedance mismatch of MXene results in low microwave absorption. In this work, 2D/2D MXene@TiO2 composites were synthesized via a simple hydrothermal oxidation method, TiO2 is derived in situ from MXene without adding any additional Ti precursors. TiO2 with low permittivity can effectively regulate the impedance matching and enhance loss mechanisms. The MXene@TiO2-6 h composite shows a reflection loss (RL) of −58.3 dB at 11.36 GHz with a thickness of 1.75 mm, and the maximum effective absorption bandwidth (EAB) is 4.08 GHz (13.92–18 GHz) at 1.26 mm. Furthermore, the 2D/2D composite can obtain efficient microwave absorption at different frequencies by adjusting the thickness; RL can reach −39.1 dB at 5.04 GHz with a thickness of 3.5 mm. The radar cross section (RCS) of MXene@TiO2-6 h is lower than −19 dB m2 at −60–60°, and the minimum RCS is −56 dB m2 at 15°. This work provides a valuable experience in developing microwave absorption materials.
研究领域:
材料科学
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电磁学
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DOI
高影响因子
MATERIALS CHARACTERIZATION
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2025
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IF 5.5
Bin Tian,Xinzhu Gan,Zhigang Wang,Yong Xu,Lin Wang,Conghe Xu,Ling Li
In this study, TiO 2 nanosheets were directly grown on ZrO 2 fibers by employing a solvothermal technique without requiring a TiO 2 seed layer, targeting thermal radiation shielding applications. The crystalline form and microstructure of the TiO 2 nanosheets were characterized using SEM, Raman, XRD, XPS, and TEM. The infrared thermal radiation extinction properties of the TiO 2 nanosheets were evaluated using DRS and effective specific extinction coefficient ( e *), and their thermal endurance at high temperatures was also assessed. The results showed that, within the infrared band of 2.5 to 8.5 μm, the TiO 2 nanosheet arrays with a thickness of 423 nm enhanced the e* of ZrO 2 fibers by 58.59 %. At similar coating thicknesses, nanosheet coatings exhibited superior thermal radiation shielding performance compared to nanoparticle coatings. These findings suggest that ZrO 2 fibers loaded with TiO 2 nanosheets are promising candidates for thermal radiation shielding in aerogels or extreme environmental conditions.
研究领域:
材料科学
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热防护技术
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DOI
高影响因子
Journal of Materials Chemistry A
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2017
·Vol. 5
·期 6
·2619-2628
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IF 8.867
Yuzhen Zhu,Zaixiang Xu,Wenya Jiang,Shuxian Zhong,Leihong Zhao,Song Bai
The utilization of a metal cocatalyst is a promising route to improve the solar-to-chemical conversion efficiency of semiconductor-based photocatalysts. The efficiency of the improvement is greatly dependent on the architectural structure of the metal cocatalysts, especially the catalytically active sites on the surface of the cocatalysts. In this article, Pd nanosheets with different sizes have been hybridized with TiO2 nanosheets to disclose how the edge of Pd cocatalysts influences the photocatalytic performance of TiO2–Pd hybrid structures in the reduction of CO2 to fuels. It was found that the highest photocatalytic activity was realized by small Pd nanosheets with the highest edge density on the TiO2 nanosheets. The reason is that the edges of the nanosheets act as the highly active sites for the CO2 reduction reaction. To further verify the edge-dependent photocatalytic performance, Pd nanorings were also deposited on the TiO2 nanosheets, which further improve the photocatalytic activity as compared with original nanosheets resulting from the additional edge sites exposed on the side of the hollow interior in the rings. This work underlines the importance in the edge engineering on the surface of cocatalysts in realizing high-performance photocatalytic applications.
研究领域:
材料科学
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能源化学
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环境科学
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DOI
高影响因子
RSC Advances
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2015
·Vol. 5
·期 13
·9861-9864
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IF 3.84
Furong Wang,Guoqiang Zhang,Zhao Zhao,Huaqiao Tan,Weixing Yu,Xuming Zhang,Zaicheng Sun
A simple hydrothermal method is developed to directly grow TiO2 nanosheets on a bare glass substrate. By tuning the reaction conditions, the thickness of the TiO2 nanosheet layer can be tuned from tens to hundreds of nanometers. This TiO2 nanosheet layer exhibits good transparency due to the air pocket existing inside the thin film layer between nanosheets. On the other hand, the TiO2 layer has a good hydrophilic surface and good wettability, especially under UV light illumination. The degradation of dye (rhodamine B) results indicate that the TiO2 nanosheet coating has excellent photocatalytic activity. All these results demonstrate that the TiO2 nanosheet coating could be a highly transparent self-cleaning coating.
研究领域:
材料科学
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环境科学
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纳米技术
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DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2021
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IF 19.503
Zhi-Wen Wang,Qiang Wan,Ying-Zhang Shi,Huan Wang,Yue-Yue Kang,Shu-Ying Zhu,Sen Lin,Ling Wu
Ultrathin TiO 2 nanosheet (NST) with abundant Ti 3+ sites is developed as a photocatalyst which exhibits a high yield (147.2 μmol g −1 h −1 ) and selectivity (96.8%) for CO 2 to CH 4 . The results of in situ FTIR, in situ EPR and density functional theory (DFT) calculation suggest that CO 2 would be selectively activated on NST surface via forming the bridging Ti···CO 2 − ···Ti coordination species which not only lowers the activation energy barrier, but also determines the selectivity of CH 4 . Additionally, NST with the better separation and transfer ability for photogenerated electrons-holes can fleetly supply the electrons to CO 2 molecules for high efficiently producing CH 4 via the Ti-C coordination bond. Finally, a possible mechanism of the synergistic effect about coordination-activation and photocatalysis is discussed at a molecule level. This work would offer a perspective for designing an effective photocatalyst and tailoring the selectivity of products by coordination activation.
研究领域:
材料科学
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环境科学
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化学
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DOI
高影响因子
Journal of Materials Chemistry C
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2020
·Vol. 9
·期 5
·1593-1603
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IF 7.059
Guoming Gao,Ximeng Wang,Qifeng Chen,Caibo Xie,Jie Zheng,Huailin Fan,Lulu Ma,Ruifang Guan,Yanfen Fang,Xun Hu
Surface fluorinated TiO2 has received extensive attention in recent years due to the improved photocatalytic reactivity compared with that of pure TiO2. However, the synergy of surface fluorine (FS) and oxygen vacancy (VO) is not clear and needs further study. Here we systematically studied the effect of FS, VO and acidic sites of TiO2 nanosheets on the selective photocatalytic oxidation of benzylamine to imine. The photocatalytic activity first increased and then decreased as the content of FS decreased and VO increased. The photocatalytic activity reached a summit with the imine yield of 92.1% over TiO2-B-6 h, which is mainly due to the synergy between FS and adjacent VO, forming the frustrated Lewis pair that boosts the activation of O2. The varied contents of FS and VO not only cause an evident change in the amount of acidic sites, but also affect the band structure and separation efficiency of charge carriers. The experimental and calculation results demonstrate that the coexistence of FS and VO boosted the separation efficiency, density and mobility of photogenerated charge carriers, resulting in the improved photocatalytic activity. The improved photocatalytic activity can be attributed to the combined effects of FS, VO and acidic sites. This work provides a strategy for the explicit regulation of surface species on TiO2 nanosheets for improved photocatalytic activity.
研究领域:
材料科学
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环境科学
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化学工程
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DOI
高影响因子
ACS Applied Nano Materials
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2019
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IF 0
Xianke Zhang,Li Li,Yuqiang Zeng,Feng Liu,Jujun Yuan,Xiaokang Li,Yi Yu,Xiurong Zhu,Zuzhou Xiong,Huajun Yu,Yingmao Xie
Surface-fluorinated ultrathin anatase TiO2 nanosheets with exposed (001) crystal planes were synthesized via a relatively low temperature solvothermal route. These two-dimensional (2D) TiO2 nanosheets demonstrated higher photocatalytic activity for degrading Rhodamine B (RhB) under simulated sunlight illumination than the corresponding sample with less fluorine ions (F–) content, which indicates the positive effect of F– on the enhanced photocatalytic performance of TiO2 nanosheets. Furthermore, 2D/2D TiO2/g-C3N4 nanosheet heterojunctions were fabricated through a solvent evaporation process. The photocatalysis test showed that TiO2/g-C3N4 exhibited higher photocatalytic performance for degrading RhB under simulated solar light illumination than pure g-C3N4 and TiO2 nanosheets. Based on free radical trapping experiments, superoxide radicals (·O2–) and photoinduced holes (h+) were determined to be the predominant active species for photodegrading RhB. A direct Z-scheme charge transfer mechanism is proposed to understand the enhanced photocatalytic activity in TiO2/g-C3N4 nanosheet heterojunctions.
研究领域:
材料科学
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环境科学
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DOI
APPLIED SURFACE SCIENCE
·
2015
·
IF 2.711
Zhiqiao He,Juntao Tang,Jie Shen,Jianmeng Chen,Shuang Song
TiO 2 nanosheets modified with various concentrations of sulfuric acid have been synthesized through hydrothermal treatment at 240 °C followed by heat treatment at 105 °C. Compared with untreated TiO 2 nanosheets, the H 2 SO 4 -modified samples exhibited markedly improved quantum yield (QY), energy returned on energy invested (EROEI), and turnover number (TON) for CO 2 reduction to CH 4 under visible-light irradiation. As supported by physical-chemical characterization, the enhanced photocatalytic activities can be attributed to acidification promoting the formation of hydroxyl groups (Brønsted acidic sites) and oxygen vacancies/Ti 3+ species. Thus, efficient charge separation and transfer to the TiO 2 surface for both CO 2 reduction and the accompanying H 2 O oxidation is facilitated. The highest activity for CO 2 photoreduction to CH 4 was obtained with TiO 2 nanosheets with 0.5 mol L −1 H 2 SO 4 , with QY, EROEI, and TON of 0.726‰, 0.335‰, and 83.124, respectively. Furthermore, the catalyst maintained stable performance throughout five successive recyclability test runs.
研究领域:
材料科学
·
环境科学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）