检索结果-南通市图书馆

Oxidative dehydrogenation of propane over Ni-Mo-Mg-O catalysts

在线全文

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2012年第1期21卷 43-48页

作者： Lin Wang Wei Chu Chengfa Jiang Yuefeng Liu Jie Wen Zaiku Xie Department of Chemical Engineering Sichuan UniversityChengdu 610065SichuanChina Shanghai Research Institute of Petrochemical Technology SINOPECShanghai 201209China

In this work, a series of Ni-Mo-Mg-O catalysts with mesoporous structure prepared by sol-gel method were investigated for the oxidative dehydrogenation of propane （ODHP）. The techniques of temperature-programmed reduction with H2 （H2-TPR）, N2 adsorption-desolption, Fourier transform infrared spectroscopy （FT-IR）, X-ray diffraction （XRD） and X-ray photoelectron spectra （XPS） were employed for catalyst characterization. It is found that the activity of the catalysts for ODHP increases first and then decreases with the increase of Mo content. The catalyst with a Mo/Ni atomic ratio of 1/1 exhibits the best catalytic activity, which gives the propene selectivity of 81.4% at a propane conversion of 11.3% under 600 ~C and maintains the good catalytic performance for 22 h on stream. This is related not only to its high reducibility and dispersion as revealed by TPR and XRD, but also to the formation of more selective oxygen species on the MoOz-NiO interface as identified by XPS.

关键词： nickel oxide molybdenum oxide mole ratio oxidative dehydrogenation of propane propene

Preparation of Pt-MoOx/CNT Electrode and Its Electrocatalytic Property for Ethanol Electrooxidation

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2006年第7期24卷 881-886页

作者：王明涌陈金华崔坤在刘博周海晖旷亚非 State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University Changsha Hunan 410082 China

MoOx, a non-noble secondary catalyst instead of noble metal Ru, was dispersed on carbon nanotubes （CNT） and then the primary catalyst Pt was electrodeposited on MoOx/CNT/graphite electrode by potential-step method. CNT used was grown directly on graphite disk by chemical vapor deposition. The Pt-MoOx/CNT/graphite electrode was characterized by scanning electron microscopy and energy dispersive X-ray spectroscopy. The electrocatalytic property and the long-term cyclic stability of Pt-MoOx/CNT/graphite electrode for ethanol oxidation have been investigated in 1.0 mol/L CH3CH2OH＋0.1 mol/L H2SO4 by cyclic voltammetry. On the other hand, the effect of the loading mass of MoOx on specific activity of Pt-MoOx/CNT/graphite electrode and the activation energy of ethanol oxidation were investigated. The Pt-MoOx/CNT/graphite electrode shows good long-term cyclic stability. 82% value of peak current density at the oxidation peak around 0.69 V （vs. SCE） remains after 500 cycles, which is higher than those of Pt/CNT/graphite and Pt-Ru/CNT/graphite electrodes with the corresponding values of 55% and 72%, respectively.

关键词： ethanol oxidation carbon nanotube molybdenum oxide platinum

Writing with atoms： Oxygen adatoms on the MoO2/Mo（110） surface

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2013年第12期6卷 929-937页

作者： Sergey A. Krasnikov Olaf Lubben Barry E. Murphy Sergey I. Bozhko Alexander N. Chaika Natalia N. Sergeeva Brendan Bulfin and Igor V. Shvets Centre for Research on Adaptive Nanostructures and Nanodevices School of Physics Trinity College Dublin Dublin 2 Ireland Institute of Solid State Physics Russian Academy of Sciences Chernogolovka Moscow District 142432 Russia School of Chemistry University of Leeds Leeds LS2 9JT UK

Writing at the nanoscale using the desorption of oxygen adatoms from the oxygen-rich MoO2＋x/Mo（110） surface is demonstrated by scanning tunnelling microscopy （STM）. High-temperature oxidation of the Mo（110） surface results in a strained, bulk-like MOO2（010） ultra-thin film with an O-Mo-O trilayer structure. Due to the lattice mismatch between the Mo（110） and the MOO2（010）, the latter consists of well-ordered molybdenum oxide nanorows separated by 2.5 nm. The MoO2（010）/Mo（110） structure is confirmed by STM data and density functional theory calculations. Further oxidation results in the oxygen-rich MoOa^x/Mo（110） surface, which exhibits perfectly aligned double rows of oxygen adatoms, imaged by STM as bright protrusions. These adatoms can be removed from the surface by scanning （or pulsing） at positive sample biases greater than 1.5 V. Tip movement along the surface can be used for controlled lithography （or writing） at the nanoscale, with a minimum feature size of just 3 nm. By moving the STM tip in a predetermined fashion, information can be written and read by applying specific biases between the surface and the tip.

关键词： scanning tunnellingmicroscopy inelastic tunnelling atom manipulation molybdenum oxide

Methanol Oxidation over TiO_2-modified Multi-walled Carbon Nanotubes Supported Pt-Mo Electrocatalyst

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2011年第3期27卷 486-489页

作者： WANG Xiu-yu JIANG Yuan-sheng ZHU Hong ZHANG Jing-chang Institute of Modern Catalyst Beoing University of Chemical TechnologyBeo＇ing 100029 P. R. China School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 P. R. China

In order to develop a novel and high-performance catalytic material for direct methanol fuel cells（DMFC）, molybdenum oxide as a co-catalyst with Pt on multi-walled carbon nanotubes which were modified by titanium dio-xide（denoted as CNTs@TiO2） was investigated. The physicochemical characterizations of the catalysts were carried out via X-ray diffraction（XRD）, transmission electron microscopy（TEM） and X-ray photoelectron spectroscopy（XPS）. Cyclic voltammetry（CV） showed that the CO-tolerance performance increased in the sequence of Pt/CNTs Pt/CNTs@TiO2Pt-Mo/CNTs@TiO2. The improved CO-tolerance performance of the Pt-Mo/CNTs@TiO2 catalyst can be attributed to the combined beneficial effects of highly dispersed Pt nanoparticles on the CNTs, the existence of oxygen holes in the MoO3 layer structure and the oxidation capability of TiO2.

关键词： Methanol oxidation Direct methanol fuel cell molybdenum oxide Platinum

Optimization and degradation of rubrene/C_(70) heterojunction solar cells

在线全文

学校读者我要写书评

暂无评论

Optoelectronics Letters 2012年第2期8卷 93-96页

作者：陈子国刘彭义侯林涛麦文杰吴冰 Department of Physics Jinan University Siyuan Lab. Jinan University

Small molecule organic solar cells （OSCs） with the structure of indium tin oxide （1TO）/molybdenum trioxide （MOO3）（5 nm）/rubrene （x nm）/fullerene （C70）（y nm）/2, 9-dimethyl-4, 7-diphenyl-1, 10-phenanthroline （BCP）（6 nm）/aluminum （A1）（150 nm） are fabricated. The thickness of active layer for the devices is investigated in details. The results show that the optimum thicknesses of rubrene layer and C70 layer are 30 nm and 25 nm, respectively. The degradation of the device is also investigated. The result indicates that the open-circuit voltage （Voo） does not change, while the short-circuit current density （Jsc）, fill factor （FF） and power conversion efficiency （PCE） decrease continuously with time. The degradation can be attributed to the oxygen in ambient diffusing and infiltrating into the active materials and reacting with C70 in cells, which can result in the increase of interfacial series resistance.

关键词： Conversion efficiency Electric resistance Heterojunctions Indium compounds molybdenum oxide Open circuit voltage Tin Tin oxides

Investigation on the Performance of Supported molybdenum Carbide for the Partial Oxidation of Methane

在线全文

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2003年第1期12卷 23-30页

作者： Quanli Zhu, Jian Yang, Jiaxin Wang, Shengfu Ji, Hanqing WangState Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China Stt. Key Lab. Oxo Synth./Sel. Oxid. Lanzhou Inst. of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

The performance of supported and unsupported molybdenum carbide for thepartial oxidation of methane (POM) to syngas was investigated. An evaluation of the catalystsindicates that bulk molybdenum carbide has a higher methane conversion during the initial stage buta lower selectivity to CO and H_2/CO ratio in the products. The rapid deactivation of the catalystis also a significant problem. However, the supported molybdenum carbide catalyst shows a muchhigher methane conversion, increased selectivity and significantly improved catalytic stability. Thecharacterization by XRD and BET specific area measurements depict an improved dispersion ofmolybdenum carbide when using alumina as a carrier. The bulk or the supported molybdenum carbideexists in the β-MO_2C phase, while it is transformed into molybdenum dioxide postcatalysis which isan important cause of molybdenum carbide deactivation.

关键词： molybdenum carbide molybdenum oxide partial oxidation of methane syngas deactivation

MoO_3-TiO_2纳米晶体复合材料光降解糖蜜(英文)

在线全文

学校读者我要写书评

暂无评论

催化学报 2012年第2期33卷 261-266页

作者： Madhukar NAVGIRE Ajeet YELWANDE Deepak TAYDE Balasaheb ARBAD Machhindra LANDE Department of Chemistry Dr.Babasaheb Ambedkar Marathwada University

A MoO3-TiO2 nanocrystalline composite material was prepared by a simple solgel *** synthesized material was charac-terized by X-ray diffraction,scanning electron microscopy with an electron dispersion spectroscopy,transmission electron microscopy,and Fourier transform infrared *** is a dark brown pigment found in wastewater from the sugar industry and it pollutes *** polluted water is generally referred to as molasses and it undergoes fermentation and is solely responsible for water,soil,and air *** synthesized catalytic material was found to be effective in degrading molasses under UV-visible *** of treated and untreated molasses was carried out by measuring its color,chemical oxygen demand,biological oxygen demand,pH,and total dissolved *** from these analyses indicate the effective photodegradation of the *** methodology has several advantages such as high photocatalytic activity,non-toxicity,cleanliness,and reusability of the catalytic material.

关键词： sol-gel molybdenum oxide titanium oxide photodegradation molasses pollution control

Photoelectrochemical study of MoO_3 assorted morphology films formed by thermal evaporation

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2016年第5期25卷 798-804页

作者： R.Senthilkumar G.Anandhababu T.Mahalingam G.Ravi Department of Physics Alagappa University Department of Electrical and Computer Engineering Ajou University

molybdenum oxide nanostructured thin films were grown on fluorine doped tin oxide（FTO）, indium doped tin oxide（ITO） and ordinary glass substrates by thermal evaporation process without vacuum and catalysts using molybdenum trioxide（MoO） powder as a source material and oxygen as a carrier *** morphologies including nanobelts, disks and hexagonal rod-like nanostructures were obtained by changing the source and substrate temperatures during the growth of MoOthin films. Structural parameters, morphology, composition and surface features of the films were characterized by XRD, SEM, EDAX,XPS, AFM and Raman spectroscopy. The films were orthorhombic in structure with preferred orientation along（0 1 0） plane. Morphology analysis reveals randomly aligned nanobelts with 40 nm in thickness and a width of 800 nm and 3–12 mm in length. The disks have 1.5 μm diameters, 1 μm thickness and hexagonal rod-like nanostructures with a length, breath and width of 2 μm, 1 μm and 100 nm are formed. The samples were investigated under dark and photocurrent conditions in HSOaqueous solution as a function of applied potential. The photocurrent density of samples prepared on ITO and FTO substrate samples were compared and the results are discussed.

关键词： molybdenum oxide Thermal evaporation Nanostructure Photoelectrochemical cell

THE AROMATIZATION MECHANISM OF METHANE OVER Mo/HZSM-5 ZEOLITE CATALYSTS WITHOUT USING OXIDANTS

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 1996年第3期 210-221页

作者： XIE Mao-Song YANG Xu CHEN Wen-Heng TAO Long-Xiang WANG Xuc-Lin XU Gui-Fen (Dalian Institute of Chemical Physics, The Chinese Academy of SciencesDalian Liaoning 116023)WANG Ling-Sheng XU Yi-De LIU She-Tian GUO Xie-Xian (State Key Laboratory of Catal

The highly selective aromatic convention of methane withoutusing oxidants over bifunctional zeolite catalysts at a suitable condition hasbeen studied. The heterolytic splitting of methane for its activation and themolybdenum carbene-like complex or CH2 radicals as intermediate aresuggested. The activation and aromatization of the methane perhapsproeecded at the interface between the Mo species and the zeolite support.

关键词： methane aromatization benzene HZSM-5 molybdenum oxide