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Controllable incorporation of CdS nanoparticles into TiO_2 nanotubes for highly enhancing the photocatalytic response to visible light

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Science china chemistry 2009年第12期52卷 2148-2155页

作者： WANG ChengLin1,SUN Lan1,XIE KunPeng1 & LIN ChangJian1,2 1 Department of chemistry,College of chemistry and Chemical Engineering,xiamen university,xiamen 361.05,china 2.state key laboratory of physical chemistry of solid surfaces,xiamen university,xiamen 361.05,china 1. Department of chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China 2. state key laboratory of physical chemistry of solid surfaces Xiamen University Xiamen 361005 China

A constant current electrochemical deposition was employed to incorporate CdS nanoparticles into the TiO2 nanotube arrays (TiO2NTs). The size and amount of CdS nanoparticles in TiO2NTs (CdS@TiO2NTs) were controllable via modulating current,deposition time and electrolyte concentration. It was revealed,from the scanning electron microscopy (SEM) images and X-ray photoelectron spectroscopy (XPS) in depth profile,that CdS nanoparticles were filled into TiO2 nanotubes. A shift of the absorption edge toward the visible region under the optimal electrodeposition condition was observed with the diffuse reflectance spectroscopy (DRS). A 5-fold enhancement in the photocurrent spectrum for TiO2NTs was observed and the photocurrent response range was significantly extended into the visible region because of the CdS incorporation. Compared with pure TiO2NTs,under a visible light irradiation,CdS@TiO2NTs exhibited a 3.5-fold improvement of photocatalytic activity,which was demonstrated by the photocatalytic decomposition of Rhodamine B (RhB).

关键词： TiO2 nanotube CdS photocatalysis RhB

A simple solvothermal route towards the morphological control of ZnO and tuning of its optical and photocatalytic properties

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Science china chemistry 2010年第8期53卷 1711-1717页

作者： JIANG YaQi,LI FangFang,SUN Ran,XIE ZhaoXiong & ZHENG LanSun state key laboratory for physical chemistry of solid surfaces Department of chemistry,College of chemistry and Chemical Engineering,xiamen university,xiamen 361.05,china 1. state key laboratory for physical chemistry of solid surfaces Department of chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China

ZnO nanoparticles with different morphologies were solvothermally synthesized by controlling the alkali (sodium hydroxide) concentration in an isopropanol *** products were characterized by means of powder X-ray diffraction,UV-visible absorption spectra,scanning electron microscopy,transmission electron microscopy,and selected area electron *** morphologies of the formed ZnO nanocrystals were dependent on the concentration of the alkali,and with increases of sodium hydroxide concentration,the ZnO nanocrystals evolved from rod to hexagonal bipyramid,and then to a flower-like *** flower-like nanostructure resulted from the etching of the hexagonal bipyramid by the excess *** photoluminescence and photocatalytic properties of the prepared ZnO were *** difference of green emission among the ZnO nanocrystals indicated that a higher sodium hydroxide concentration led to a higher level of *** size,the surface structure and defects in the ZnO nanocrystals affected its photo-degradation characteristics.

关键词： zinc oxide solvothermal method nanocrystal photoluminescence photocatalysis

An Ab Initio Study of N_2O Decomposition on MgO Catalyst

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Chinese Chemical Letters 1998年第6期9卷 583-586页

作者： Xin LU Xin XU Nan Qin WANG and Qian Er ZHANG(state key laboratory for physical chemistry of solid surfaces, Institute of physical chemistry,Department of chemistry, xiamen university, xiamen 361.05) xiamen Univ Dept Chem State Key Lab Phys Chem Solid Surfaces Inst Chem Phys Xiamen 361005 Peoples R China

Ab initio calculations based on density functional theory have been used to study thedecompsition of N_2O on MgO. The reaction is predicted to occur on O_3c and O_(4c) atoms, but not onO_(5c) atoms, with an activation barrier of 25-27 kcal/mol, in agreement with the experimental valueof 35 kcal/mol. Natural bond orbital analysis shows that the reaction leaves O ad-atoms on thosesurface O anions to form a peroxide-like 'O^2_(2-)' species. The )O-O bond stretching frequency ispredicted to be in the range from 820 cm(-1) to 825 cm(-1).

关键词： Ab initio calculation N_2O decomposition MgO catalyst

SYNTHESIS OF POLYCATECHOL WITH ELECTROCHEMICAL ACTIVITY AND ITS PROPERTIES

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Chinese Journal of Polymer Science 2002年第6期20卷 517-524页

作者： Yong Kong Shao-lin Mu Bing-wei Mao Department of chemistry School of Sciences, Yangzhou university Yangzhou 225002, china state key laboratory of physical chemistry of the solid Surface, xiamen university,xiamen 361.05, china Yangzhou Univ Sch Sci Dept Chem Yangzhou 225002 Peoples R China xiamen Univ State Key Lab Phys Chem Solid Surface Xiamen 361005 Peoples R China

The electrochemical polymerization of catechol on platinum has been carried out using repeated potential cycling between -0.2 and 1.1 V (versus SCE). The electrolytic solution consisted of 0.2 mol dm(-3) catechol, 0.5 mol dm(-3) NaCl and 0.1 mol dm(-3) Na2HPO4 with pH 8.72. Catechol can not be polymerized at pH greater than or equal to 10.12. Polycatechol has an electrochemical lactivity at pH less than or equal to 4. The anodic and cathodic peak potentials of polycatechol shift towards more negative values as the pH of the solution increases from 1 to 4. The electrochemical activity of polycatechol hardly changes in this pH region, but it decreases slowly with time. This is caused by oxygen in air, which leads to an irreversible oxidation of polycatechol. This property is favorable for protecting metals from corrosion. Raman and FTIR spectra of polycatechol and catechol are quite different. AFM images of polycatechol films provide evidence that the image of the oxidized state of polycatechol is markedly different from that of the reduced one. This difference is caused by doping and dedoping of polycatechol.

关键词： catechol polycatechol electrochemical activity Raman spectra FTIR spectra AFM images

Study on Highly Active Catalysts and a Once-Through Process for Methanol Synthesis from Syngas

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Journal of Natural Gas chemistry 2003年第1期12卷 49-55页

作者： Xin Dong, Bingshun Shen, Hongbin Zhang, Guodong Lin, Youzhu YuanDepartment of chemistry, state key laboratory of physical chemistry for solid surfaces, xiamen university, xiamen 361.05, china Department of chemistry State Key Laboratory of Physical Chemistry for Solid Surfaces Xiamen University Xiamen 361005 China

Highly active CNT-promoted co-precipitated Cu-ZnO-Al_2O_3 catalysts,symbolized as Cu_iZn_jAl_k-x%CNTs, were prepared, and their catalytic activity for once-throughmethanol synthesis from syngas was investigated. The results illustrated that, under the reactionconditions (at 493 K, 5.0 MPa, the volume ratio of H_2/CO/CO_2/N_2= 62/30/5/3, GHSV= 4000 h^(-1),the observed single-pass CO-conversion and methanol-STY over a Cu_6Zn_3Al_1-12.5%CNTs catalystreached 64% and 1210 mg/(h-g), which was about 68% and 66% higher than those (38% and 730 mg/(h·g))over the corresponding CNT-free catalyst, Cu-6Zn_3Al_1, respectively. The characteristic studies ofthe catalysts revealed that appropriate incorporation of a minor amount of the CNTs into theCu_iZn_jAl_k brought about little change in the apparent activation energy of the methanol synthesisreaction, however, led to a considerable increase in the catalyst's active Cu surface area andpronouncedly enhanced the stationary-state concentration of active hydrogen-adspecies on the surfaceof the functioning catalyst, which would be favorable to increasing the rate of the COhydro-genation reactions. Moreover, the operation temperature for methanol synthesis over theCNT-promoted catalysts can be 10-20 degrees lower than that over the corresponding CNT-free contrastsystem, which would contribute considerably to an increase in equilibrium CO-conversion andCH_3OH-yield.

关键词： carbon nanotubes Cu_iZn_jAl_k-x%CNTs catalyst methanol synthesis CO/CO_2 hydrogenation syngas

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Foreword

电化学 2012年第5期18卷 385-386页

作者： Dr.Bin Ren Professor of chemistry state key laboratory of physical chemistry of solid surfaces,College of chemistry and Chemical Engineering,xiamen university,xiamen 361.05,china

On the request of ***-Gang Sun,Editor-in-Chief of Journal of Electrochemistry,I served asthe guest editor for this International Special Issueon Current *** Journal of Electrochemistry was founded in1995 associated

关键词：电化学电化学平衡电解质电解

The　Active　Oxygen　Species　for　Oxidative　Coupling　of　Methane　over　CeO_2/BaF_2　Catalyst　by　in　Situ　Confocal　Microprobe　Raman　Spectroscopy

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Chemical Research in Chinese Universities 1997年第1期13卷 93-95页

作者： LONG Rui qiang and WAN Hui lin (Department of chemistry and state key laboratory for physical chemistry of the solid Surface, xiamen university, xiamen, 361.05) xiamen UNIV DEPT CHEMXIAMEN 361005PEOPLES R CHINA xiamen UNIV STATE KEY LAB PHYS CHEM SOLID SURFACEXIAMEN 361005PEOPLES R CHINA

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关键词： Oxygen species Oxidative coupling Methane In situ Raman spectroscopy

Synthesis and characterization of stable osmafuran starting from HC≡CCH(OH)C≡CH and OsHCl(CO)(PPh_3)_3

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Science china chemistry 2010年第9期53卷 1978-1981页

作者： ZHANG Hong,LIN Ran,LUO Ming & XIA HaiPing state key laboratory for physical chemistry of solid surfaces College of chemistry and Chemical Engineering,xiamen university,xiamen 361.05,china 1. state key laboratory for physical chemistry of solid surfaces College of chemistry and Chemical Engineering Xiamen University Xiamen 361005 China

This paper presents a new convenient route to prepare osmafuran starting from readily accessible HC≡C CH(OH)C≡CH and OsHCl(CO)(PPh3)*** of a solution of OsHCl(CO)(PPh3)3 in dichloromethane with HC≡C CH(OH)C≡CH,followed by the addition of acetic acid,produced osmafuran [Os(CHC(PPh3)CO(CH2CH3))Cl(CO)(PPh3)2]Cl(2).2 has been isolated in good yield and fully characterized.1H and 13C NMR spectra show the characteristic downfield chemical shifts of the ring hydrogen and carbon *** and X-ray diffraction data provide strong evidence for the aromatic nature of *** due to the effect of the phosphonium substituent,2 exhibits remarkable thermal stability,air stability and lower reactivity.

关键词： osmafuran metallaaromatics phosphonium salt synthesis stability

PERFORMANCE　AND　CHARACTERIZATION　OF　NOVEL　ELECTROCATALYST　FOR　OXYGEN　REDUCTION

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Chinese Chemical Letters 1995年第9期6卷 807-810页

作者： YongYANG Jin Kua YOU Zu Geng LIN(state key laboratory for physical chemistry or the solid Surface and Department of chemistry, xiamen university, xiamen, 361.05) xiamen Univ Dept Chem Xiamen 361005 Peoples R China xiamen Univ State Key Lab Phys Chem Solid Surface Xiamen 361005 Peoples R China

Abstract: The preparation and characterization of novel electrocatalyst for oxygen reduction have been carried out. It is found that heated Fe-PPy/C catalysts show good catalytic activity f'or oxygen reduction in alkaline or acid solutions. Direct correlation between ESR signal and catalytic activity of the catalysts has been obtained. Some implications from this catalytic system have also been discussed.

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