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Journal of Rare Earths 2021年第5期39卷 495-503页

作者： Luozhen Jiang Xin Tao Li'na Li Wen Xia Rui Si Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204China University of Chinese Academy of Sciences Beijing 100049China Division of China TILON Group Technology LimitedShanghai 200090China

Ceria supported platinum catalyst has now been widely studied due to its excellent activity for CO oxidatio ***,the electron state of active metal center is still an open *** this work,a ce ria nanorod support was prepared and platinum(Pt)with 0.9 at%was deposited using an impregnation method to obtain Pt/CeO_(2)*** the help of"light-off"experiment and temperatureprogrammed reduction under CO(CO-TPR)test,the conclusion is proposed that the process of hydrogen reduction can enhance the activity of CO oxidation reaction for the generation of optimal active Pt *** innovative near-situ X-ray absorption fine structure(XAFS)technique was used to investigate the chemical state of central Pt atom during the reaction process,clearly demonstrating that the high oxidized state of Pt does harm to the activity for CO oxidation while the relatively reductive Pt exhibits high activity,and the different oxidized state and chemical environment of Pt during every process has been ***,the activity of our Pt/CeO_(2)catalyst is superior to that of most of the previous reports about CO catalytic oxidation by Pt based ***,the optimal active species(Pt-O_(4))have been identified after hydrogen reduction,which could be a possible key strategy to control the oxidation of Pt.

关键词： platinum catalyst Ceria support CO oxidation Structure-activity relationship X-ray absorption fine structure Rare earths

Hydroisomerization performance of platinum supported on ZSM-22/ZSM-23 intergrowth zeolite catalyst

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Petroleum Science 2013年第2期10卷 242-250页

作者： Chi Kebin Zhao Zhen Tian Zhijian Hu Sheng Yan Lijun Li Tianshu Wang Bingchun Meng Xiangbin Gao Shanbin Tan Mingwei Liu Yanfeng State Key Laboratory of Heavy Oil Processing China University of Petroleum Petrochemical Research Institute PetroChina Company Limited Dalian Institute of Chemical Physics Chinese Academy of Sciences

Hydroisomerization catalysts Pt/ZSM-22, Pt/ZSM-23, and Pt/ZSM-22/ZSM-23 were prepared by supporting Pt on ZSM-22, ZSM-23, and intergrowth zeolite ZSM-22/ZSM-23, respectively. The typical physicochemical properties of these catalysts were characterized by X-Ray Diffraction （XRD）, N2 absorption-desorption, Pyridine-Fourier Transform Infrared （Py-FTIR）, Transmission Electron Microscopy （TEM）, X-Ray Fluorescence （XRF）, Scanning Electron Microscopy （SEM） and NH3- Temperature Programmed Desorption （NH3-TPD）, and the performance of these catalysts in n-dodecane hydroisomerization was evaluated in a continuous down-flow fixed bed with a stainless steel tubular reactor. The characterization results indicated that the intergrowth zeolite ZSM-22/ZSM-23 possessed the dual structure of ZSM-22 and ZSM-23, and the catalyst Pt/ZSM-22/ZSM-23 had similar pores and weak acidity to Pt/ZSM-22 and Pt/ZSM-23 catalysts. Moreover, Pt/ZSM-22/ZSM-23 catalyst showed a high selectivity in hydroisomerization of long chain n-alkanes to mono-branched isomers. The evaluation results for n-dodecane hydroisomerization indicated that the activity of Pt/ZSM-22/ZSM-23 was the lowest, while the hydroisomerization selectivity was the highest among the three catalysts. The maximum yield of i-dodecane product was 68.3% over Pt/ZSM-22/ZSM-23 at 320 ℃.

关键词： ZSM-22/ZSM-23 intergrowth zeolite platinum catalyst n-dodecane hydroisomerization

LaO_(x)(OH)_(y) supported platinum catalysts for CO oxidation:Deactivation by formation of lanthanum carbonate

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Journal of Rare Earths 2021年第3期39卷 297-304,I0003页

作者： Luozhen Jiang Junxiang Chen Rui Si Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204China Shanghai Synchrotron Radiation Facility Zhangjiang LaboratoryShanghai 201204China Division of China TILON Group Technology LimitedShanghai 200090China University of Chinese Academy of Sciences Beijing 100049China

platinum catalyst for CO oxidation has been studied for decades,due to its high activity and good *** this work,we prepared three different lantha num oxide or hydroxide supports(LaO_(x)(OH)_(y)),and deposited platinum(Pt) with 0.5 at% via an impregnation approach to synthesize Pt/LaO_(x)(OH)_(y) ***,we find that these catalysts perform a poor stability for the CO oxidation *** fresh and used samples were comprehensively characterized by multiple techniques including power X-ray diffraction(XRD),X-ray absorption fine structure(XAFS),transmission electron microscopy(TEM),temperature-programmed reduction by carbon monoxide(CO-TPR) and thermogravimetric analysis(TGA),to demonstrate that the oxidized platinum atoms or clusters,without any component of Pt-Pt metallic bond,are highly dispersed on the surface of LaO_(x)(OH)_(y).Furthermore,the as-formed lanthanum carbonate(La_(2)O_(2)CO_(3)) during the exposure to ambient circumstances or in the reaction atmosphere of CO+O_(2),severely impair the reactivity of Pt/LaO_(x)(OH)_(y).On the basis of the obtained experimental results,we have drawn a conclusion that the oxidized P_(t)O_(x) atoms or PtxOy clusters are the active species for CO oxidation,while the formation of lanthanum carbonate is the origin of deactivation on reactivity.

关键词： platinum catalyst Lanthanum oxide Lanthanum hydroxide CO oxidation Structure-activity relationship Rare earths

Zero-oxidation state precursor assisted fabrication of highly dispersed and stable Pt catalyst for chemoselective hydrogenation ofα,β-unsaturated aldehydes

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Nano Research 2023年第5期16卷 6085-6093页

作者： Yu Liang Mark Douthwaite Xiaoyang Huang Binbin Zhao Qiong Tang Lei Liu Jinxiang Dong College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan 030024China Cardiff Catalysis Institute School of ChemistryCardiff UniversityMain BuildingPark PlaceCardiffCF103ATUK

The chemoselective hydrogenation ofα,β-unsaturated aldehydes is a key strategy for the synthesis of fine ***,we developed an efficient method of depositing Pt particles on FeO_(x)/*** strategy is dependent on using a platinumdivinyltetramethyldisiloxane complex(Pt^(0)-DVTMS)as the precursor,which we demonstrate can be removed through a H_(2)-treatment under mild ***,in turn,allowed for the synthesis of catalysts with well dispersed Pt *** presence of FeO_(x) species also aided Pt dispersion;when coated onto SBA-15,FeO_(x) strongly interacted with dissociated Pt species,inhibiting both Pt aggregation and metal *** cinnamaldehyde as a modelα,β-unsaturated aldehyde,it was demonstrated that this catalyst was highly selective towards the unsaturated alcohol and no obvious loss in activity was observed over five *** catalyst was determined to be significantly more effective than an analogous catalyst prepared using chloroplatinic acid as a precursor,evidencing the importance of using the Pt0-DVTMS *** corroborate the excellent catalytic performance to highly dispersed Pt-species,whereby Pt0 and Pt^(2+) play a critical role in activating H_(2) and the C=O *** research demonstrates that the Pt precursor can have a significant impact on the physicochemical properties and thus,the performance of the final *** also evidences how metal support interactions can dramatically influence selectivity in such hydrogenation *** novel catalyst preparation protocol,using a DVTMS ligand for Pt impregnation,offers a facile approach to the design of multi-component heterogeneous catalysts.

关键词： platinum catalyst zero-oxidation state stability chemoselective hydrogenation α,β-unsaturated aldehydes

A review of Pt-based electrocatalysts for oxygen reduction reaction

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Frontiers in Energy 2017年第3期11卷 268-285页

作者： Changlin ZHANG Xiaochen SHEN Yanbo PAN Zhenmeng PENG Department of Chemical and Biomolecular Engineering University of Akron Akron OH 44325 USA

Development of active and durable electro- catalyst for oxygen reduction reaction （ORR） remains one challenge for the polymer electrolyte membrane fuel cell （PEMFC） technology. Pt-based nanomaterials show the greatest promise as electrocatalyst for this reaction among all current catalytic structures. This review focuses on Pt- based ORR catalyst material development and covers the past achievements, current research status and perspectives in this research field. In particular, several important categories of Pt-based catalytic structures and the research advances are summarized. Key factors affecting the catalyst activity and durability are discussed. An outlook of future research direction of ORR catalyst research is provided.

关键词： oxygen reduction reaction (ORR) electrocatalysis platinum catalyst activity durability

Synthesis Gas Production from Natural Gas on Supported Pt catalysts

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Journal of Natural Gas Chemistry 2006年第1期15卷 21-27页

作者： Mariana M. V. M. Souza Octávio R. Macedo Neto Martin Schmal NUCAT/PEQ/COPPE

Auto-thermal reforming of methane, combining partial oxidation and reforming of methane with CO2 or steam, was carried out with Pt/Al2O3, Pt/ZrO2 and Pt/CeO2 catalysts, in a temperature range of 300-900℃. The auto-thermal reforming occurs in two simultaneous stages, namely, total combustion of methane and reforming of the unconverted methane with steam and CO2, with the O2 conversion of 100% starting from 450℃. For combination with CO2 reforming, the Pt/CeO2 catalyst showed the lowest initial activity at 800℃, and the highest stability over 40 h on-stream. This catalyst also presented the best performance for the reaction with steam at 800℃. The higher resistance to coke formation of the catalyst supported on ceria is due to the metal-support interactions and the higher mobility of oxygen in the oxide lattice.

关键词： methane steam reforming CO2 reforming partial oxidation auto-thermal reforming platinum catalyst ceria zirconia

Effect of load-cycling amplitude on performance degradation for proton exchange membrane fuel cell

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Chinese Chemical Letters 2021年第10期32卷 3159-3163页

作者： Kun Wang Ning Li Yanan Yang Shaojie Ke Zhengping Zhang Meiling Dou Feng Wang State Key Laboratory of Chemical Resource Engineering Beijing Key Laboratory of Electrochemical Process and Technology for MaterialsBeijing University of Chemical TechnologyBeijing 100029China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China

Durability is one of the critical issues to restrict the commercialization of proton exchange membrane fuel cells(PEMFCs) for the vehicle *** practical dynamic operation significantly affects the PEMFCs durability by corroding its key *** this work,the degradation behavior of a single PEMFC has been investigated under a simulated automotive load-cycling operation,with the aim of revealing the effect of load amplitude(0.8 and 0.2 A/cm2 amplitude for the current density range of0.1-0.9 and 0.1-0.3 A/cm^(2),respectively) on its performance degradation.A more severe degradation on the fuel cell performance is observed under a higher load amplitude of 0.8 A/cm^(2) cycling operation,with$10.5% decrease of cell voltage at a current density of 1.0 A/*** larger loss of fuel cell performance under the higher load amplitude test is mainly due to the frequent fluctuation of a wider potential *** characterizations analyses indicate that the Pt nanoparticles in cathodic catalyst layer grow faster with a higher increase extent of particle size under this circumstance because of their repeated oxidation/reduction and subsequent dissolution/agglomeration process,resulting in the degradation of platinum catalyst and thus the cell ***,the detected microstructure change of the cathodic catalyst layer also contributes to the performance failure that causes a distinct increase in mass transfer resistance.

关键词： Proton exchange membrane fuel cell Durability Load-cycling amplitude Degradation mechanism platinum catalyst