AUSTRALIAN JOURNAL OF CHEMISTRY
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2018
·Vol. 71
·期 12
·965-970
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IF 1.059
Lingfeng Ruan,Rongying Jiang,Jing Liu,Song Liu
BaTiO3/TiO2 and CaTiO3/TiO2 bilayer-type photocatalyst films have been prepared and characterised by X-ray diffraction, Raman, X-ray photoelectron spectroscopy, UV-vis, and scanning electron microscopy techniques. The photodeposition of silver was done to confirm the reduction positions of the titanate/TiO2 films. Silver deposited preferentially on the side of TiO2 for BaTiO3/TiO2 whereas on the side of CaTiO3 for CaTiO3/TiO2. These results imply that the direction of photogenerated electron transfer is coincident with the semiconductor physical principles. Upon exposure to light, electron–hole pairs are generated and subsequently separated by an internal electrostatic field in the titanate–TiO2 heterojunction.
研究领域:
材料科学
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物理化学
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DOI
高影响因子
THIN SOLID FILMS
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2018
·
IF 1.939
Qing-Er Zhao,Wei Wen,Yu Xia,Jin-Ming Wu
This study establishes the feasibility to enhance the photocatalytic activity of nanostructured TiO 2 thin films through embedding the free spaces with sol-gel TiO 2 nanoparticles . With the various additives in the aqueous H 2 O 2 solutions, thin films of TiO 2 nanorods , nanowires, and nanoflowers were precipitated on metallic Ti substrates via the Ti-H 2 O 2 interactions at 80 °C for 72 h. About 3–7% anatase TiO 2 nanoparticles were then embedded successfully among the free spaces of the nanostructures by immersing them into a titania sol followed by lifting up with an appropriate withdrawing speed. When utilized to assist degradations of phenol in water under UV light illumination, the photocatalytic activity for thin films of nanorods and nanowires after filling with sol-gel TiO 2 nanoparticles is 76% and 136% higher than that of the pristine films, respectively. The films also exhibited high stability upon cycling tests, which could thus find potential applications in wastewater treatments.
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
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
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2012
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IF 2.421
Z.L. Zhang,M. Wan,Y.L. Mao
A TiO 2 -based composite, ZnFe 2 O 4 /TiO 2 , was prepared with a commercial TiO 2 (Degussa P25) and ZnFe 2 O 4 nanopowders using a simple method. The composite was characterized by X-ray diffraction (XRD), UV–vis absorption spectrum, surface photovoltage spectroscopy (SPS) and SEM. The composite presents an enhanced photovoltaic effect compared with the pure TiO 2 . The trap distributions of TiO 2 and ZnFe 2 O 4 /TiO 2 composite were investigated and the energy levels of TiO 2 and ZnFe 2 O 4 were analyzed. The results indicate that the enhancement of photovoltaic effect is mainly due to the increase of photo-generated carrier concentration and improvement of the separation efficiency of photo-generated carriers by the addition of ZnFe 2 O 4 .
研究领域:
材料科学
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光催化
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DOI
高影响因子
INTERNATIONAL JOURNAL OF PHOTOENERGY
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2020
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IF 1.88
Jing Yan,Xiaojuan Li,Bo Jin,Min Zeng,Rufang Peng
A series of TiO2, TiO2/Pd, and TiO2/PdO hollow sphere photocatalysts was successfully prepared via a combination of hydrothermal, sol-immobilization, and calcination methods. The structure and optical properties of the as-prepared samples were characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, Brunauer-Emmett-Telleranalysis, Barrett-Joyner-Halenda measurement, and UV-Vis diffuse reflectance spectroscopy. The photocatalysis efficiencies of all samples were evaluated through the photocatalytic degradation of rhodamine B under visible light irradiation. Results indicated that TiO2/PdO demonstrated a higher photocatalytic activity (the photocatalytic degradation efficiency could reach up to 100% within 40 min) than the other samples and could maintain a stable photocatalytic degradation efficiency for at least four cycles. Finally, after using different scavengers, superoxide and hydroxyl radicals were identified as the primary active species for the effectiveness of the TiO2/PdO photocatalyst.
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 CATALYSIS B-ENVIRONMENTAL
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2019
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IF 14.229
Yaru Wang,Jianjun Zhao,Xianqiang Xiong,Shengwei Liu,Yiming Xu
Anatase TiO 2 is the most studied environmental photocatalyst, but its efficiency is still not high enough to enable application. Herein we report a positive effect of Ni 2+ ions on the photocatalytic reaction in neutral aqueous solution. On addition of 1 mM Ni(ClO 4 ) 2 , the rates of phenol oxidation on TiO 2 and 0.5 wt.% Pt/TiO 2 increased by factors of 2.1 and 8.0, respectively. Meanwhile, the formation of organic intermediate was reduced, and the removal of total organic content was enhanced. Interestingly, Ni 2+ concentration did not change with irradiation time. Moreover, a maximum rate of phenol degradation was observed with Ni 2+ ions, occupying half the surface of TiO 2 or Pt/TiO 2 , where Ni(OH) + was more active than Ni(OH) 2 . X-ray photoelectron spectroscopy identified a Ni 3+ species produced in absence of phenol. A (photo)electrochemical study revealed that Ni 2+ oxidation was favored over H 2 O oxidation, whereas Ni 2+ and Pt inhibited and facilitated O 2 reduction, respectively. It is proposed that the adsorbed Ni(OH) + on TiO 2 is oxidized to Ni 3+ by the photogenerated holes of TiO 2 , followed by regeneration through phenol oxidation. The Ni 2+ -catalyzed organic oxidation then promotes the Pt-catalyzed O 2 reduction, and vice visa, resulting into the greatly improved efficiency of charge separation. This work highlights the possibility of Ni 2+ ions as the hole mediator of organic oxidation over a semiconductor.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
ACS Omega
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2024
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IF 3.7
Linsong Wu,Haoran Shi,Xingzhi Wang,Shiwei Lu,Xiang Chen
In this study, a series of nano-TiO2 composite materials, including nano-TiO2, nano-SnO2/TiO2, nano-SiO2/TiO2, and nano-Fe2O3/TiO2, were successfully synthesized via the gaseous detonation method. Comprehensive characterization of the synthesized samples was carried out through X-ray diffraction (XRD), transmission electron microscopy/high-resolution TEM (TEM/HRTEM), scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), Brunauer–Emmett–Teller (BET) method, and Fourier transform infrared (FTIR) analysis, which unveiled the significant influence of precursor types on the microstructure of the composite materials. Specifically, the incorporation of Sn4+ promoted the transformation of TiO2 to the rutile phase, reducing particle sizes from 25 to 19 nm and increasing the specific surface area from 44 to 86 m2/g. In contrast, the introduction of SiO2 impeded the rutile phase formation, leading to a marked reduction in particle size to 14 nm and an enhancement of the specific surface area to 104 m2/g. Furthermore, the presence of Fe3+ promoted the formation of the rutile phase and enabled particle growth to 44 nm. These findings not only deepen the understanding of structural control in the synthesis of nano-TiO2 composite materials via the gaseous detonation method but also highlight the critical role of precursor selection in determining the properties of the resulting materials.
研究领域:
材料科学
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纳米技术
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2023
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IF 11.4
Nini Zhang,Xiangmei Li,Yanglong Guo,Yun Guo,Qiguang Dai,Li Wang,Wangcheng Zhan
Crystal engineering of metal oxide supports represents an emerging strategy to improve the catalytic performance of noble metal catalysts in catalytic oxidation of chlorinated volatile organic compounds (CVOCs). Herein, Pt catalysts on a TiO2 support with different crystal phases (rutile, anatase, and mixed phase (P25)) were prepared for catalytic oxidation of 1,2-dichloroethane (DCE). The Pt catalyst on P25-TiO2 (Pt/TiO2-P) showed optimal activity, selectivity, and stability, even under high-space velocity and humidity conditions. Due to the strong interaction between Pt and P25-TiO2 originating from the more lattice defects of TiO2, the Pt/TiO2-P catalyst possessed stable Pt0 and Pt2+ species during DCE oxidation and superior redox property, resulting in high activity and stability. Furthermore, the Pt/TiO2-P catalyst possessed abundant hydroxyl groups, which prompted the removal of chlorine species in the form of HCl and significantly decreased the selectivity of vinyl chloride (VC) as the main byproduct. On the other hand, the Pt/TiO2-P catalyst exhibited a different reaction path, in which the hydroxyl groups on its surface activated DCE to form VC and enolic species, besides the lattice oxygen of TiO2 for the Pt catalysts on rutile and anatase TiO2. This work provides guidance for the rational design of catalysts for CVOCs.
研究领域:
催化
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环境化学
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材料科学
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DOI
PubMed
高影响因子
RSC Advances
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2019
·Vol. 9
·期 53
·30790-30796
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IF 3.049
Haoyang Zou,Lan Wang,Huaizhi Tao,Yi Liu,Meiqi Chang,Shiyu Yao
Recently, polyacrylamide (PAM) has been widely used in polymer flooding technology to enhance oil recovery and oil production. However, the difficulty in removing hydrolysed PAM (HPAM) from wastewater still seriously blocks the further application of polymer flooding in the oilfields. Herein, we demonstrate the preparation of SiO2@TiO2:Eu3+@TiO2 core double-shell microspheres (STT) through a two-step solvothermal and sol–gel coating strategy. The as-prepared STT exhibits an ideal photocatalytic activity for the photodegradation of HPAM. More importantly, by using STT as the model, the correlation between fluorescence intensity and photocatalytic activity of the photocatalysts is investigated. The results suggest their oppositional relationship. Since many kinds of photocatalysts are utilized in the degradation of organic pollutants, it is believed that our work will not only promote the development of photocatalysis in the field of oil extraction, but also offer a convenient method for evaluating the photocatalytic activity of the photocatalysts.
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
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2019
·Vol. 23
·期 11
·3031-3041
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IF 2.531
Deng Yafeng,Ma Zhanhong,Ren Fengzhang,Wang Guangxin
In spite of the TiO 2 compact layer (TCL) being widely used, it still needs more study. This paper took Ni-doped TCLs as the research target, using an innovative two-step method perfectly prepared Ni-doped TCLs with different thicknesses. And then on the basis of Ni-doped TCLs, the TiO 2 nanorod array (TNA) films were successfully prepared. The effects of Ni-doped TCLs with different thicknesses on the morphology, structure, and photoelectric performance of TNA films were investigated. The results indicated that Ni-doped TCLs with appropriate thickness can significantly improve performance of TNA films and obtain satisfactory PCE stability with time. Compared with the TNA films based on Ni:TCL5, Ni:TCL10, and Ni:TCL30, the TNA film with Ni:TCL20 exhibited better comprehensive photoelectric performance, the DSSCs based on this TNA film achieved the highest J sc (10.191 mA cm −2 ), V oc (0.574 V), PCE (4.42%), and the most excellent PCE stability with time.
研究领域:
材料科学
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能源科学
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DOI
高影响因子
Surfaces and Interfaces
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2023
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IF 6.2
Jie Jiang,Yuqiang Ding
As a widely used semiconductor photocatalyst , TiO 2 has been explored in organic compounds hydrogenation. In this study, the hydrogenation of C=N bonds on the surface of TiO 2 was accomplished for the first time utilizing Cu 2 O/TiO 2 type-II (p-n) heterojunction . The probe reactions, hydrogenation of N -benzylphenylamine with benzyl alcohol, and N -methylation of amines with methanol exhibited that the hydrogenation of C=N bonds on TiO 2 surface can be achieved through borrowing hydrogen reaction (BH, alcohols as hydrogen source). Additionally, the BH reaction rate could be improved by adding external H + to the reaction system. The catalytic activity of Cu 2 O/TiO 2 was discovered to remain at an efficient level even after six reaction cycles.
研究领域:
化学
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材料科学
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2017
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IF 2.986
Xuefeng Zhang,Yong Liu,Shangli Dong,Zhuyu Ye,Yu Guo
A TiO 2 -Ti 3 C 2 T x nanocomposite was prepared using a simple and facile one-step hydrothermal method . The small sized TiO 2 nanoparticles were synthesized and assembled on the surface of Ti 3 C 2 T x nanosheets using Ti 3 C 2 T x itself as titanium source by in-situ technique. The microstructure of TiO 2 -Ti 3 C 2 T x nanocomposite was characterized by means of XRD、FESEM、TEM、XPS and Raman, respectively. The effects of ethanol and hydrothermal holding time on the size of TiO 2 nanoparticles were investigated. The results show that adding proper amount of ethanol into pure water results in decrease of the size of TiO 2 nanoparticles. Under ethanol-water mixed solution, increasing the time of hydrothermal treatment results in growth and even aggregation of TiO 2 nanoparticles. The TiO 2 nanoparticles with average particle size of 30 nm were obtained when the hydrothermal treatment was conducted in ethanol-water mixed solution at 200 ℃ for 12 h.
研究领域:
材料科学
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纳米技术
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2019
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IF 8.355
Suqing Wu,Haiyang Hu,Yan Lin,Junliang Zhang,Yun Hang Hu
TiO 2 is widely exploited as a photocatalyst to degrade antibiotic residues in water under UV irradiation, but it is inefficient for visible light photocatalysis due to its large band gap. Herein, it is the first time to report the photodegradation of tetracycline (TC) over TiO 2 under visible light irradiation. 25.1% of removal efficiency for TC was achieved even under 700 nm light irradiation. Furthermore, it was demonstrated that O 2 − species, which were generated from photoexciting of a surface complex between TC molecules and TiO 2 , played a critical role in the visible light photocatalytic degradation of TC. In addition, it was found that the visible light photocatalytic degradation generated different active species and intermediate products from those under UV irradiation. N-doped TiO 2 exhibited even better performance for visible-light photocatalytic degradation of TC with higher removal efficiency and larger mineralization rate, which followed different degradation-mechanism.
研究领域:
环境科学
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化学
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材料科学
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产品关联
DOI
高影响因子