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Efficient Direct Decomposition of NO over La_(0.8)A_(0.2)NiO_(3)(A=K, Ba, Y) catalysts under Microwave Irradiation

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 17-23页

作者：王浩 ZHAO Zijian DUAN Xinghui ZHOU Shijia School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

La_(0.8)A_(0.2)NiO_(3) (A=K,Ba,Y) catalysts supported on the microwave-absorbing ceramic heating carrier were prepared by the sol-gel *** crystalline phase and the catalytic activity of the La_(0.8)A_(0.2)NiO_(3)catalysts were characterized by XRD and H_(2) temperature-programmed reduction (TPR).The effects of reaction temperature,oxygen concentration,and gas flow rate on the direct decomposition of nitric oxide over the synthesized catalysts were studied under microwave irradiation (2.45 GHz).The XRD results indicated that the La_(0.8)A_(0.2)NiO_(3) catalysts formed an ABO_(3) perovskite structure,and the H_(2)-TPR results revealed that the relative reducibility of the catalysts increased in the order of La_(0.8)K_(0.2)NiO_(3)>La_(0.8)Ba_(0.2)NiO_(3)>La_(0.8)Y_(0.2)Ni O_(3).Under microwave irradiation,the highest NO conversion amounted to 98.9%,which was obtained with the La_(0.8)K_(0.2)NiO_(3) catalyst at 400℃.The oxygen concentration did not inhibit the NO decomposition on the La_(0.8)A_(0.2)NiO_(3) catalysts,thus the N_(2) selectivity exceeded 99.8%under excess oxygen at 550℃.The NOconversion of the La_(0.8)A_(0.2)NiO_(3) catalysts decreased linearly with the increase in the gas flow rate.

关键词： microwave catalysis direct decomposition of NO microwave-absorbing heating ceramics perovskite catalyst

Structures and Properties of La_(0.8)Sr_(0.2)MnO_(3+σ)^(-z) SBA-15(z=0, 1, 2, 4) perovskite catalysts

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Journal of Wuhan University of Technology(Materials Science) 2018年第1期33卷 23-29页

作者：黄学辉 NIU Pengju LI Ming LIAO Hui SHANG Xiaohui School of Materials Science and Engineering Wuhan University of Technology

Mesoporous La0.8Sr0.2MnO3＋σ/z SBA-15（z = 1, 2, 4） perovskite oxides were synthesized via hard-templating with ordered mesoporous silica SBA-15 as the template. The as-prepared samples were characterized by XRD, SEM, AFM, BET, and XPS and the catalytic activity was tested for CO oxidation. The wide-angle XRD patterns showed that La0.8Sr0.2MnO3＋σ perovskite was formed. The SEM and AFM analyses exhibited that La0.8Sr0.2MnO3＋σ by hard-templating method had much smaller particle size（18 nm） than that（40 nm） by the sol-gel method. The perovskite-type oxides La0.8Sr0.2MnO3＋σ/z SBA-15（z = 1, 2, 4） also displayed a higher BET surface area from 70 to 143.7 m^2/g and a disordered mesostructure from nitrogen sorption analysis, as well as a small-angle XRD pattern. Moreover, the La0.8Sr0.2MnO3＋σ/z SBA-15（z = 1, 2, 4） perovskite exhibited a much higher activity in CO oxidation than the conventional La0.8Sr0.2MnO3＋σ perovskite. Further analysis by the means of XPS techniques indicated that the existence of high content of Oads/Olatt species contributed to the high activity.

关键词： hard-templating sol-gel perovskite catalyst mesoporous structure CO oxidation

Effect of calcination process on performance of 3DOM CeMnO3 catalysts

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Journal of Rare Earths 2021年第9期39卷 1073-1081页

作者： Xin Liu Xinyi Lv Yongqiang Wang Chaocheng Zhao Fang Liu College of Chemical Engineering China University of Petroleum(East China)Qingdao 266580China State Key Laboratory of Petroleum Pollution Control China University of Petroleum(East China)Qingdao 266580China

A series of 3DOM CeMnO3 perovskite catalysts were prepared by poly(methyl methacrylate)hardtemplating-excessive impregnation method at calcination temperature of x℃(x=600,700,800)and the heating rate of y℃/min(y=1,2,5,10).The samples were characterized by Brunauer-Emmett-Teller method,scanning electron microscopy,transmission electron microscopy,H2-temperature programmed reduction,X-ray photoelectron spectroscopy,X-ray diffraction,moreover,the effect of the calcination process on the catalytic activity of the samples were discussed by the catalytic combustion of *** results show that the 3DOM CeMnO3 catalysts calcined at 600℃promote the formation of a perovskite structure,inhibit the reduction of the Mn4+species in the catalyst with high *** catalyst expresses the complete macroporous structure,large specific surface area(38.8 m^(2)/g),higher adsorption oxygen concentration and Mn4+substance concentration,with a low T90%=172℃.By preparing the catalysts at different calcination heating rates,it can be concluded that the catalyst possesses a high concentration of adsorbed oxygen and a low reduction temperature and a large specific surface area(40.42 m^(2)/g)greatly promotes adsorption stage catalytic oxidation reaction and catalytic combustion of toluene at low temperature under the heating rate of 5℃/*** the heating rate is 1℃/min,the catalyst has a complete macroporous structure(>250 nm),which is beneficial to the exchange of macromolecular substances during the catalytic reaction and the catalyst has a high concentration of lattice oxygen suitable for the catalysis of toluene in high temperature flue gas combustion.

关键词： Three-dimensionally ordered macroporous perovskite catalyst Calcination temperature Calcination heating rate Rare earths

Photorechargeable Properties of Metal Hydride-SrTiO_3 Electrode

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Chinese Chemical Letters 2005年第7期16卷 979-982页

作者： WenKuiZHANG XiLiTONG HuiHUANG YongPingGAN NaHUANG DepartmentofAppliedChemistry ZhejiangUniversityofTechnologyHangzhou310014

A photosensitive metal hydride electrode was prepared by modification with perovskite-type SrTiO3 photocatalyst. The photorechargeable properties of the prepared electrodes were investigated by using electrochemical cyclic voltammetry and EIS measurements. The results showed that the modified electrode exhibited the obvious photorechargeable properties. The reduction current increased remarkably under the xeon light irradiation compared with the unmodified electrode. During the photocharging process, the potential of the modified electrode shifted quickly to negative direction and a potential plateau of about -0.90V (vs. Hg/HgO) occurred at the end of light irradiation. The corresponding discharge capacity of the electrode was about 5.4 mAh/g.

关键词： perovskite catalyst strontium titanate photorechargeable properties.

环境催化中的陶瓷材料:应用与可能性(英文)

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催化学报 2012年第10期33卷 1611-1621页

作者： Nitin LABHSETWAR P.DOGGALI S.RAYALU R.YADAV T.MISTUHASHI H.HANEDA Environmental Material Division National Environmental Engineering Research Institute(CSIR-NEERI) National Institute for Materials Science(NIMS)

Environmental catalysis has been steadily growing because of the advances in its scientific and engineering aspects,as well as due to the new environmental challenges in the industrial *** development of new catalysts and materials is essential for new technologies for various environmental *** play important roles in various environmental applications including the identification,monitoring,and quantification of pollutants and their *** have important applications as sensors and photocatalysts,and they are extensively used as catalyst carriers and *** ceramics are being explored as catalysts for pollution control *** low cost,thermal and chemical stability,and capability of being tailored make them especially attractive for pollution control *** a wide variety of materials have been developed as catalyst supports,this area is still of interest with new or modified catalyst supports being frequently *** is of equal importance to develop new or modified processes for the loading of catalysts on specific *** like chemical looping combustion(CLC) and other catalytic combustion processes are raising the demands to a new *** have been working on the development of both new and modified support materials,including mesoporous materials without structural order for possible applications in CLC and other catalytic *** attempts have been made in the modification of conventional γ-Al2O3 and improved synthesis processes for supporting perovskite type *** research on environmental catalysis applications of ceramic materials and processes are also briefly discussed.

关键词： ceramics environmental catalysis perovskite catalyst carbonation catalyst support catalytic emission control chemical looping combustion

THE ROLE OF LATTICE AND GASEOUS OXYGEN ON THE OXIDATIVE COUPLING OF METHANE STUDIED BY A PULSE REACTION TECHNIQUE

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Journal of Energy Chemistry 1995年第2期 157-166页

作者： XU Yi-De** HUANG Bu-WenWEI Xin-Yun HUANG Jia-ShengState Key Laloratory of CatalysisDalian Institute of Chemical Physics, Academia SmicaDalian, Ijiaoning 116023

A comparative study of the role of lattice and gaseous oxygen in theoxidative coupling of methane over Na/Cao and CaSrTiOperovskiteoxide catalysts was performed by using a pulse reaction technique with CH,Oand mixtures of CHand *** was found that there is an oxygen species onthe Surface of Cao which is active only for the total oxidation of methane at thereaction *** oxygen *** reacted with methane andconsumed,can be regenerated by the adsorption of oxygen molecules from thegas phase or by the migration of the lattice oxysen from the bulk onto *** contrast,no such oxygen species and no reaction can be detected bymethane pulsed over CaSrTiOperovskite oxide *** heavilysuppress the non-selective oxygen species on the surface,and When 5mol%Nawas incorporated onto the surface of Cao,the sample showed no reactivityto *** oxygen exists in the gas phase,or the pulse containsmethane and oxygen,the reaction over(Cao is mai

关键词： CaO lattice oxygen perovskite catalyst oxidative coupling of methane

Preparation, Characterization of Macro-mesoporous La0.8M0.1Ce0.1Mn0.7Cu0.3O3(M=Sr, Eu) and the Catalytic Activity For NO and CO

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Preparation, Characterization of Macro-mesoporous La0.8M0.1C...