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Photocatalytic Activity of Lanthanum and Sulfur Co-doped TiO_2 Photocatalyst under visible light

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Journal of Wuhan University of Technology(Materials Science) 2008年第4期23卷 467-471页

作者： XIA Huili ZHUANG Huisheng XIAO Dongchang ZHANG Tao College of Environmental Science ＆ Engineering Donghua University Sfianghai 201620 China

A novel lanthanum and sulfur co-doped TiO2 photocatalyst was synthesized by precipitation- dipping method, and characterized by X-ray diffraction（XRD）, transmission electron microscopy（TEM） and UV-Vis diffuse reflectance spectroscopy. Compared with the S-doped TiO, La-doped TiO2 and the standard Degussa P25 photocatalysts, the lanthanum and sulfur co-doped TiO2 photocatalyst （the molar percentage of La is 3.0%） calcined at 450 ℃ for 2 h showed the strongest absorption for visible light and highest activities for degradation of reactive blue 19 dye in aqueous solution under visible light（λ〉400 nm） irradiation. It was also discovered that the co-doping of lanthanum and sulfur hindered the aggregation and growth of TiO2 particles, and the doping of lanthanum reduced slightly the phase transition temperature ofTiO2 from anatase to rutile.

关键词： photocatalysis TiO2 co-doping reactive blue 19 visible light

TEMPO visible light photocatalysis: The selective aerobic oxidation of thiols to disulfides

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Chinese Chemical Letters 2020年第6期31卷 1520-1524页

作者： Hui Xu Yu-Fei Zhang Xianjun Lang Sauvage Center for Molecular Sciences College of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China

TEMPO(2,2,6,6-tetramethylpipe ridine-1-oxyl)is well-established in orangocatalysis that usually work in synergy with transition-metal catalysis or semiconductor ***,TEMPO was turned into a visible light photocatalyst to conduct the selective aerobic oxidation of thiols into *** O2 as an oxidant,a mild and efficient protocol for the selective oxidation of thiols into disulfides including symmetrical and unsymmetrical ones with 5 mol%of TEPMO as a photocatalyst was developed at room temperature under the irradiation of 460 nm blue *** was found that a complex formed between TEMPO and thiols underpinned the visible light activity and disulfides were obtained in very high isolated *** work suggests that TEMPO takes diverse roles in for photocatalytic selective oxidative transformations with O2 as the oxidant.

关键词： Radical visible light TEMPO Aerobic oxidation Disulfides

Photocatalytic Reduction of Cr^Ⅵ by Natural Sphalerite Suspensions under visible light Irradiation

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Acta Geologica Sinica(English Edition) 2006年第2期80卷 267-272页

作者： LI Yan LU Anhuai WANG Changqiu School of Earth and Space Sciences Peking University Beijing 100871

The photocatalytic reductive capability of a natural semiconducting mineral, sphalerite has been studied for the first time. The sphalerite from the Huangshaping deposit of Hunan Province performed great photoreductive capability that 91.95% of the Cr^6＋ was reduced under 9 h visible light irradiation, higher than the 70.58% under 9.5 h UV light irradiation. The highly reductive ability results from its super negative potential of electrons in the conduction band. Furthermore, Fe substitution for Zn introduces donor states, and the oxidation process of Fe^2＋ to Fe^3＋ makes it an effective hole-scavenger. Cd and Cu substitute for Zn also reduce the bandgap and help broaden the absorbing edge towards the visible light. These substituting metal ions in natural sphalerite make it a hyper-active photocatalyst and very attractive for solar energy utilization.

关键词： natural sphalerite photoreduction Cr^6+ visible light substituting ions bandgap

Simultaneously Enhanced Activity and Selectivity for C(sp^(3))-H Bond Oxidation Under visible light by Nitrogen Doping

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Transactions of Tianjin University 2021年第4期27卷 331-337页

作者： Tingting Hou Zhuyan Gao Jian Zhang Nengchao Luo Feng Wang School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510640China State Key Laboratory of Catalysis Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

Selective oxidation of saturated C(sp^(3))-H bonds in hydrocarbon to target chemicals under mild conditions remains a signifi-cant but challenging task because of the chemical inertness and high dissociation energy of C(sp^(3))-H *** photocatalysis can induce the generation of holes and oxidative radicals,off ering an alternative way toward selective oxidation of hydrocarbons under ambient ***,we constructed N-doped TiO_(2) nanotubes(N-TNTs)that exhibited remark-able activity and selectivity for toluene oxidation under visible light,delivering the conversion of toluene and selectivity of benzaldehyde of 32% and>99%,*** mechanistic studies demonstrated that the incorporation of nitrogen induced the generation of N-doping level above the O 2p valance band,directly contributing to the visible-light response of TiO_(2).Furthermore,hydroxyl radicals generated by photogenerated holes at the orbit of O 2p were found to be unselective for the oxidation of toluene,aff ording both benzaldehyde and benzoic *** incorporation of nitrogen was able to inhibit the generation of hydroxyl radicals,terminating the formation of benzoic acid.

关键词： visible light c(sp^(3)) H oxidation N-doped TiO_(2) Selectivity Benzaldehyde

Effects of visible light on Cultured Bovine Trabecular Cells

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2004年第2期24卷 178-180,184页

作者：姜发纲郝风芹魏厚仁许德胜 Department of Ophthalmology Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430022 ChinaState Key Laboratory of Laser Technology Huazhong University of Science and Technology Wuhan 430022 China Department of Ophthalmology Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430022 China Department of Ophthalmology Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430022 China State Key Laboratory of Laser Technology Huazhong University of Science and Technology Wuhan 430022 China

To explore the biological effects of light on trabecular cells, cultured bovine trabecular cells were exposed to visible light of different wavelength with different energy. Cellular morphology, structure, proliferation, and phagocytosis were observed. The cells showed no remarkable changes when the energy was low. When the exposure energy reached 1.12 mW/cm 2, the cytoplasm showed a rough appearance, and cell proliferation and phagocytosis decreased. This phototoxicity was strong with white light (compound chromatic light), moderate with violet light or yellow light, and mild with red light.

关键词： visible light trabecular cells proliferation phagocytosis

Bioinspired C/TiO_2 photocatalyst for rhodamine B degradation under visible light irradiation

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Frontiers of Agricultural Science and Engineering 2017年第4期4卷 459-464页

作者： Jian LI Likun GAO Wentao GAN Key Laboratory of Biobased Material Science & Technology of the Education Ministry Northeast Forestry University Research Center of Wood Bionic Intelligent Science Northeast Forestry University

Papilio paris butterfly wings were replicated by a sol-gel method and a calcination process, which could take advantage of the spatial features of the wing to enhance their photocatalytic properties. Hierarchical structures of P. paris-carbon-TiO_2(PP-C-TiO_2) were confirmed by SEM observations. By applying the Brunauer-Emmett-Teller method, it was concluded that in the presence of wings the product shows higher surface area with respect to the pure TiO_2 made in the absence of the wings. The higher specific surface area is also beneficial for the improvement of photocatalytic ***, the conduction and valence bands of the PPC-TiO_2 are more negative than the corresponding bands of pure TiO_2, allowing the electrons to migrate from the valence band to the conduction band upon absorbing visible light. That is, the presence of C originating from wings in the PP-C-TiO_2 could extend the photoresponsiveness to visible light. This strategy provides a simple method to fabricate a high-performance photocatalyst,which enables the simultaneous control of the morphology and carbon element doping.

关键词： bioinspired butterfly wings C/TiO2 photocatalyst visible light

Effect of Cobalt Precursor on Microstructures and visible light Photoactivity of Doped TiO2 Powders

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Chinese Journal of Chemical Physics 2006年第5期19卷 463-468页

作者： Jing-ying Shi Wen-hua Leng Jiang-lin Cao Jian-qing Zhang Chu-nan Cao Department of Chemistry Yuquan Campus Zhejiang University Hangzhou 310027 China Department of Chemistry Quanzhou Normal College Quanzhou 352000 China

In order to develop photoactive cobalt-doped TiO2 for the degradation of organic pollutants using visible light irradiation, the effects of cobalt precursor on TiO2 microstructure were investigated. Three cobaltprecursors, i.e. COCl2, Co（NO3）2 and COSO4 with two doping levels （nominally 1% and 10%）, and two annealing temperatures （400 and 800 ℃） were adopted to prepare tile doped titania through the sol-gel method. The powder samples were characterized with XRD, SEM, BET surface area analysis and UV-Vis absorption spectroscopy, and their photocatalytic activities were evaluated by the degradation of aniline under visible light irradiation. The results showed that the distribution of titania phases, particle size, morphology, surface area and the optical absorption of the catalysts were greatly dependent on the cobalt precursors. Samples prepared from Co（NO3）2, especially for those doped at 1% and calcined at 400 ℃, showed the highest photocatalytic activity towards the degradation of aniline, and the possible reasons are discussed briefly.

关键词： Cobalt precursor Doped titania Photocatalysis visible light

C3N4 modified with single layer ZIF67 nanoparticles for efficient photocatalytic degradation of organic pollutants under visible light

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Chinese Journal of Catalysis 2020年第12期41卷 1894-1905页

作者： Peidong Su Junke Zhang Ke Xiao Shen Zhao Ridha Djellabi Xuewei Li Bo Yang Xu Zhao College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060GuangdongChina Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Department of Civil and Environmental Engineering Jackson State UniversityJacksonMS 39217USA

Uniformly distributed single layer of ZIF67-derived C3N4(ZIF67-C3N4)was synthesized and applied to the photocatalytic degradation of methylene blue(MB)under visible *** indicated that the obtained ZIF67-C3N4 has a maximum specific surface area of 541.392 m^2/g,which is much larger than that of raw C3N4 of 97.291 m^2/*** investigation of C3N4 amount involved in ZIF67-C3N4 on the photoactivity revealed that 2.57 g ZIF67 with 0.3 g C3N4,which named ZIF67-C3N4(0.3)exhibited superior photocatalytic *** than 90%of MB at 10 mg/L was degraded within 70 min with the addition of 0.01 g ZIF67-C3N4(0.3),while this time required for raw C3N4 was over 140 *** effects of pH of solution,initial concentration of MB and dosage of C3N4 in ZIF67-C3N4 composites on the photocatalytic efficiency for MB degradation were also *** experiments indicated that the photo-induced holes(h^+)and superoxide radicals(O2-·)were mainly responsible for MB *** is anticipated that the insertion of ZIF67 nanoparticles not only increases the adsorption capacity of C3N4 but also promotes the generation and migration of the photo-induced active species.

关键词： Metal organic frameworks Photocatalysis C3N4 ZIF67 visible light

Tunable localized surface plasmon resonances in MoO_(3-x)-TiO_(2) nanocomposites with enhanced catalytic activity for CO_(2) photoreduction under visible light

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Chinese Journal of Catalysis 2020年第7期41卷 1125-1131页

作者： Shunji Xie Haikun Zhang Guodong Liu Xuejiao Wu Jinchi Lin Qinghong Zhang Ye Wang State Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy MaterialsNational Engineering Laboratory for Green Chemical Productions of AlcoholsEthers and EstersCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005FujianChina

The photocatalytic reduction of CO2 with H2O to fuels and chemicals using solar energy is one of the most attractive but highly difficult *** far,only a very limited number of photocatalysts has been reported to be capable of catalyzing the photocatalytic reduction of CO2 under visible *** utilization of the localized surface plasmon resonance(LSPR)phenomenon is an attractive strategy for developing visible-light ***,we have succeeded in synthesizing plasmonic MoO3?x-TiO2 nanocomposites with tunable LSPR by a simple solvothermal *** well-structured nanocomposite containing two-dimensional(2D)molybdenum oxide(MoO3?x)nanosheets and one-dimensional(1D)titanium oxide nanotubes(TiO2-NT)showed LSPR absorption band in the visible-light region,and the incorporation of TiO2-NT significantly enhanced the LSPR absorption *** MoO3?x-TiO2-NT nanocomposite is promising for application in the photocatalytic reduction of CO2 with H2O under visible light irradiation.

关键词： Photocatalysis Carbon dioxide visible light Localized surface plasmon resonance MoO_(3-x)-TiO_(2) nanocomposite