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Bimetallic CoNi single atoms supported on three-dimensionally ordered mesoporous chromia:highly active catalysts for n-hexane combustion
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作者 Xiuqing Hao Yuxi Liu +4 位作者 Jiguang Deng Lin Jing Jia Wang Wenbo Pei Hongxing Dai 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第7期1122-1137,共16页
Developing the alternative supported noble metal catalysts with low cost,high catalytic efficiency,and good resistance toward carbon dioxide and water vapor is critically demanded for the oxidative removal of volatile... Developing the alternative supported noble metal catalysts with low cost,high catalytic efficiency,and good resistance toward carbon dioxide and water vapor is critically demanded for the oxidative removal of volatile organic compounds(VOCs).In this work,we prepared the mesoporous chromia-supported bimetallic Co and Ni single-atom(Co_(1)Ni_(1)/meso-Cr_(2)O_(3))and bimetallic Co and Ni nanoparticle(Co_(NP)Ni_(NP)/mesoCr_(2)O_(3))catalysts adopting the one-pot polyvinyl pyrrolidone(PVP)-and polyvinyl alcohol(PVA)-protecting approaches,respectively.The results indicate that the Co_(1)Ni_(1)/meso-Cr_(2)O_(3)catalyst exhibited the best catalytic activity for n-hexane(C_(6)H_(14))combustion(T_(50%)and T_(90%)were 239 and 263℃ at a space velocity of 40,000 mL g^(-1)h^(-1);apparent activation energy and specific reaction rate at 260℃ were 54.7 kJ mol^(-1)and 4.3×10^(-7)mol g^(-1)_(cat)s^(-1),respectively),which was associated with its higher(Cr^(5+)+Cr^(6+))amount,large n-hexane adsorption capacity,and good lattice oxygen mobility that could enhance the deep oxidation of n-hexane,in which Ni_(1) was beneficial for the enhancements in surface lattice oxygen mobility and low-temperature reducibility,while Co_(1) preferred to generate higher contents of the high-valence states of chromium and surface oxygen species as well as adsorption and activation of n-hexane.n-Hexane combustion takes place via the Mars van Krevelen(MvK)mechanism,and its reaction pathways are as follows:n-hexane→olefins or 3-hexyl hydroperoxide→3-hexanone,2-hexanone or 2,5-dimethyltetrahydrofuran→2-methyloxirane or 2-ethyl-oxetane→acrylic acid→CO_x→CO_(2)and H_(2)O. 展开更多
关键词 Three-dimensional ordered mesoporous chromium oxide Supported bimetallic single-atom catalyst Cobalt-nickel single atoms n-Hexane combustion Catalytic reaction mechanism
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Enhanced activation of peroxymonosulfate by Fe/N co-doped ordered mesoporous carbon with dual active sites for efficient removal of m-cresol 被引量:1
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作者 Donghui Li Wenzhe Wu +6 位作者 Xue Ren Xixi Zhao Hongbing Song Meng Xiao Quanhong Zhu Hengjun Gai Tingting Huang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期130-144,共15页
The novel Fe-N co-doped ordered mesoporous carbon with high catalytic activity in m-cresol removal was prepared by urea-assisted impregnation and simple pyrolysis method.During the preparation of the Fe-NC catalyst,th... The novel Fe-N co-doped ordered mesoporous carbon with high catalytic activity in m-cresol removal was prepared by urea-assisted impregnation and simple pyrolysis method.During the preparation of the Fe-NC catalyst,the complexation of N elements in urea could anchor Fe,and the formation of C3N4during urea pyrolysis could also prevent migration and aggregation of Fe species,which jointly improve the dispersion and stability of Fe.The FeN4sites and highly dispersed Fe nanoparticles synergistically trigger the dual-site peroxymonosulfate (PMS) activation for highly efficient m-cresol degradation,while the ordered mesoporous structure of the catalyst could improve the mass transfer rate of the catalytic process,which together promote catalytic degradation of m-cresol by PMS activation.Reactive oxygen species (ROS) analytic experiments demonstrate that the system degrades m-cresol by free radical pathway mainly based on SO_(4)^(-)·and·OH,and partially based on·OH as the active components,and a possible PMS activation mechanism by 5Fe-50 for m-cresol degradation was proposed.This study can provide theoretical guidance for the preparation of efficient and stable catalysts for the degradation of organic pollutants by activated PMS. 展开更多
关键词 Degradation PEROXYMONOSULFATE Fe(II)/Fe(III)/FeN4 Ordered mesopores carbon catalyst Radical
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Preparation, Characterization, Photocatalytic Activity of S and Ag co-Doped Mesoporous Titania Photocatalysts
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作者 姚淑华 郑志慧 +1 位作者 陈爽 石中亮 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第6期732-738,I0004,共8页
In order to improve the photocatalytic performance of mesoporous titania under visible light, a series of photocatalysts of S and Ag co-doped mesoporous titania have been successfully prepared by template method using... In order to improve the photocatalytic performance of mesoporous titania under visible light, a series of photocatalysts of S and Ag co-doped mesoporous titania have been successfully prepared by template method using thiourea, AgNO3 and tetrabutyl titanate as precursors and Pluronic P123 (EO20PO70EO20) as template. Scanning electron microscopy (SEM), X-ray diffraction (XRD), nitrogen adsorption-desorption measurements, and UV-visible spectroscopy (UV-Vis) were employed to characterize the morphology, crystal structure, surface structure, and optical absorption properties of the samples. The microcrystal of the photocatalysts consisted of anatase phase and was approximately present in the form of spherical particle. The photocatalytic performance was studied by photodegradation methyl orange (MO) in water under UV and visible light irradiation. The calcination temperature and the doping content influenced the photoactivity. In addition, the possibility of cyclic usage of co-doped mesoporous titania was also confirmed, the photocatalytic activity of mesoporous titania remained above 89% of that of the fresh sample after being used four times. It was shown that the co-doped mesoporous titania could be activated by visible light and could thus be potentially applied for the treatment of water contaminated by organic pollutants. The synergistic effect of sulfur and silver co-doping played an important role in improving the photocatalytic activity. 展开更多
关键词 mesoporous titania S and Ag co-doping Doped catalyst Photocatalytic activity Template method Dye decomposition
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Synthesis and Performance of Mesoporous Phosphotungstic Acid/Alumina Composite as a Novel Oxidative Desulfurization Catalyst 被引量:6
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作者 颜学敏 XIONG Lin MEI Ping 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第2期237-241,共5页
A series of mesoporous phosphotungstic acid/alumina composites (HPW/Al_2O_3) with various HPW contents were synthesized by evaporation-induced self-assembly method. These composites were characterized by nitrogen ad... A series of mesoporous phosphotungstic acid/alumina composites (HPW/Al_2O_3) with various HPW contents were synthesized by evaporation-induced self-assembly method. These composites were characterized by nitrogen adsorption-desorption, TEM, FTIR, and UV-vis, and were tested as catalysts in oxidation desulfurization of model fuel composed of dibenzothiophene (DBT) and hydrocarbon, using H202 as the oxidant. These composites exhibited high activity in catalytic oxidation of DBT in model fuel and good reusing ability. The best performance was achieved by using the mesoporous HPW/Al_2O_3 with 15wt% HPW content, which resulted in a DBT conversion of 98% after 2 h reaction at 343 K, and it did not show significant activity degradation after 3 recycles. Characterization results showed that the mesoporous structure of alumina and the Keggin structure of HPW were preserved in the formed composite. These results suggested that HPW/ Al_2O_3 could be a promising catalyst in oxidative desulfurization process. 展开更多
关键词 mesoporous alumina tungstophosphoric acid oxidative desulfurization catalyst
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Synthesis and applications of mesoporous Cu-Zn-Al_2O_3 catalyst for dehydrogenation of 2-butanol 被引量:7
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作者 Deren Fang Wanzhong Ren +5 位作者 Zhongmin Liu Xiufeng Xu Lei Xu Hongying Lǔ Weiping Liao Huimin Zhang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2009年第2期179-182,共4页
A series of mesoporous Cu-Zn-Al2O3 materials have been synthesized at ambient temperature and their structure was characterized by XRD, N2 physical adsorption and TPR techniques. Their catalytic applications for the d... A series of mesoporous Cu-Zn-Al2O3 materials have been synthesized at ambient temperature and their structure was characterized by XRD, N2 physical adsorption and TPR techniques. Their catalytic applications for the dehydrogenation of 2-butanol to methyl ethyl ketone (MEK) were evaluated in a fixed-bed flow reactor at atmospheric pressure. It is demonstrated from the XRD patterns that both the as-synthesized samples and calcined samples have the typical XRD patterns of meso-structured materials and the results of N20 chemical adsorption showed that Cu was embedded in the framework of the mesoporous materials and homogeneously dispersed in the mesoporous Cu-Zn-Al2O3 materials. The catalytic activity of 2-butanol dehydrogenation was varied in the order of CZA(10) 〈 CZA(CP) 〈 CZA(20) 〈 CZA(30); while the selectivity of MEK was increased in the order of CZA(CP) 〈 CZA(10) 〈 CZA(20) 〈CZA(30). 展开更多
关键词 Cu-Zn-Al2O3 mesoporous materials dehydrogenation of 2-butanol catalyst
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Mesoporous polyoxometalate-based ionic hybrid as a highly effective heterogeneous catalyst for direct hydroxylation of benzene to phenol 被引量:4
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作者 Pingping Zhao Yunyun Zhang +2 位作者 Daokuan Li Hongyou Cui Lipeng Zhang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第2期334-341,共8页
Self‐assembled mesoporous polyoxometalate‐based ionic hybrid catalyst,[PxyDim]2.5PMoV2,was prepared by combining p‐xylene‐tethered diimidazole ionic liquid[PxyDim]Cl2with Keggin‐structured V‐substituted polyoxom... Self‐assembled mesoporous polyoxometalate‐based ionic hybrid catalyst,[PxyDim]2.5PMoV2,was prepared by combining p‐xylene‐tethered diimidazole ionic liquid[PxyDim]Cl2with Keggin‐structured V‐substituted polyoxometalate H5PMo10V2O40.The obtained hybrid was shown to be a mesostructured and hydrophobic material with good thermal stability.In the H2O2‐based hydroxylation of benzene to phenol,the hybrid showed extraordinary catalytic activity and rate,and quite stable reusability.The unique hydrophobic properties and mesoporous structure of the hybrid were responsible for its excellent catalytic performance. 展开更多
关键词 POLYOXOMETALATE mesoporous Benzene hydroxylation Heterogeneous catalyst PHENOL
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A highly stable and active mesoporous ruthenium catalyst for ammonia synthesis prepared by a RuCl_3/SiO_2-templated approach 被引量:7
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作者 Yaping Zhou Yongcheng Ma +4 位作者 Guojun Lan Haodong Tang Wenfeng Han Huazhang Liu Ying Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第1期114-123,共10页
Molecular nitrogen is relatively inert and the activation of its triple bond is full of challenges and of significance.Hence,searching for an efficiently heterogeneous catalyst with high stability and dispersion is on... Molecular nitrogen is relatively inert and the activation of its triple bond is full of challenges and of significance.Hence,searching for an efficiently heterogeneous catalyst with high stability and dispersion is one of the important targets of chemical technology.Here,we report a Ba‐K/Ru‐MC catalyst with Ru particle size of 1.5–2.5 nm semi‐embedded in a mesoporous C matrix and with dual promoters of Ba and K that exhibits a higher activity than the supported Ba‐Ru‐K/MC catalyst,although both have similar metal particle sizes for ammonia synthesis.Further,the Ba‐K/Ru‐MC catalyst is more active than commercial fused Fe catalysts and supported Ru catalysts.Characterization techniques such as high‐resolution transmission electron microscopy,N2 physisorption,CO chemisorption,and temperature‐programmed reduction suggest that the Ru nanoparticles have strong interactions with the C matrix in Ba‐K/Ru‐MC,which may facilitate electron transport better than supported nanoparticles. 展开更多
关键词 mesoporous carbon Semi‐embedded Ru/Carbon catalyst High dispersion Ammonia synthesis
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Wheat flour-derived N-doped mesoporous carbon extrudes as an efficient support for Au catalyst in acetylene hydrochlorination 被引量:4
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作者 Jie Liu Guojun Lan +2 位作者 Yiyang Qiu Xiaolong Wang Ying Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第10期1664-1671,共8页
We recently reported an N‐doped mesoporous carbon(N‐MC)extrudate,with major quaternary N species,prepared by a cheap and convenient method through direct carbonization of wheat flour with silica,which has excellent ... We recently reported an N‐doped mesoporous carbon(N‐MC)extrudate,with major quaternary N species,prepared by a cheap and convenient method through direct carbonization of wheat flour with silica,which has excellent catalytic performance in acetylene hydrochlorination.Herein,we examined the activity of Au supported on N‐MC(Au/N‐MC)and compared it with that of Au supported on nitrogen‐free mesoporous carbon(Au/MC).The acetylene conversion of Au/N‐MC was 50%at 180°C with an acetylene space velocity of 600 h–1 and VHCl/VC2H2 of 1.1,which was double the activity of Au/MC(25%).The introduced nitrogen atoms acted as anchor sites that stabilized the Au3+species and inhibited the reduction of Au3+to Au0 during the preparation of Au/N‐MC catalysts. 展开更多
关键词 Au catalyst Mercury free catalyst Acetylene hydrochlorination N doped mesoporous carbon
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EFFECTS OF AMINO GROUPS AND MICROSTRUCTURE OF ORGANIC MESOPOROUS SILICA SUPPORTED METALLOCENE CATALYSTS ON ETHYLENE POLYMERIZATION 被引量:1
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作者 唐涛 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第1期93-100,共8页
Mesoporous silica (MS), 3-aminopropyltriethoxysilane (APTES) modified mesoporous silica (AMS), bis(3- trimethoxysilylpropyl)amine modified mesoporous silica (BAMS) and APTES modified solid spherical silica ... Mesoporous silica (MS), 3-aminopropyltriethoxysilane (APTES) modified mesoporous silica (AMS), bis(3- trimethoxysilylpropyl)amine modified mesoporous silica (BAMS) and APTES modified solid spherical silica (AS) were prepared and used to immobilize metallocene catalysts for ethylene polymerization. Gel permeation chromatography results showed that polyethylenes (PEs) catalyzed by AMS (or BAMS) supported metallocene catalysts at the molar ratios of Al/Zr = 100, 300 and 500 were of bimodal molecular weight distribution (BMWD); while PEs catalyzed by the above catalysts at the molar ratios of Al/Zr 〉 800 were of monomodal molecular weight distribution (MMWD). However, MS (or AS) supported metallocene catalysts could only produce PEs with MMWD in spite of the molar ratio of Al/Zr. It was because that AMS (or BAMS) supported catalysts possessed two active sites for ethylene polymerization at low molar ratios of Al/Zr due to the combination effects of mesopore geometrical constraint and amino groups of the supports, which was confirmed by X-ray photoelectron spectroscopy. This brings forward a novel and easy method for the synthesis of polyolefin with BMWD. 展开更多
关键词 Organic mesoporous silicas Supported metallocene catalysts POLYETHYLENE Bimodal molecular weight distribution.
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Aerobic oxidative coupling of alcohols and amines to imines over iron catalysts supported on mesoporous carbon 被引量:1
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作者 Longlong Geng Jinling Song +4 位作者 Bin Zheng Shujie Wu Wenxiang Zhang Mingjun Jia Gang Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第9期1451-1460,共10页
Direct oxidative coupling of an alcohol and amine,with air or molecular oxygen as the oxygen source,is an environmentally friendly method for imine synthesis.We developed an Fe catalyst supported on mesoporous carbon... Direct oxidative coupling of an alcohol and amine,with air or molecular oxygen as the oxygen source,is an environmentally friendly method for imine synthesis.We developed an Fe catalyst supported on mesoporous carbon(denoted by FeOx/HCMK-3) for this reaction with excellent activity and recyclability.FeOx/HCMK-3 was prepared by impregnating HNO3-treated mesoporous carbon(CMK-3) with iron nitrate solution.The highly dispersed FeOx species give FeOx/HCMK-3 high reducibility and are responsible for the high catalytic performance.Imine synthesis over FeOx/HCMK-3 follows a redox mechanism.The oxygen species in FeOx/HCMK-3 participate in the reaction and are then regenerated by oxidation with molecular O2.The reaction involves two consecutive steps:oxidative dehydrogenation of an alcohol to an aldehyde and coupling of the aldehyde with an amine to give an imine.Oxidative dehydrogenation of the alcohol is the rate-determining step in the reaction. 展开更多
关键词 Iron catalyst Imine synthesis Oxidative coupling mesoporous carbon Molecular oxygen
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Highly selective production of phenol from benzene over mesoporous silica-supported chromium catalyst:Role of response surface methodology in optimization of operating variables 被引量:3
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作者 Milad Jourshabani Alireza Badiei +1 位作者 Negar Lashgari Ghodsi Mohammadi Ziarani 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第11期2020-2029,共10页
A Cr/SBA-16 catalyst was prepared using Cr(NO3)3 as a precursor and mesoporous silica SBA-16 as a support via a simple impregnation method. The catalyst was characterized using wide-angle X-ray diffraction (XRD), ... A Cr/SBA-16 catalyst was prepared using Cr(NO3)3 as a precursor and mesoporous silica SBA-16 as a support via a simple impregnation method. The catalyst was characterized using wide-angle X-ray diffraction (XRD), low-angle XRD, N2 adsorption-desorption, transmission electron microscopy, and ultraviolet-visible spectroscopy. The catalyst activity was investigated in the direct bydroxylation of benzene to phenol using H2O2 as the oxidant. Various operating variables, namely reaction temperature, reaction time, amount of H2O2, and catalyst dosage, were optimized using central composite design combined with response surface methodology (RSM). The results showed that the correla- tion between the independent parameters and phenol yield was represented by a second-order polynomial model. The high correlation coefficient (R2), i.e., 0.985, showed that the data predicted using RSM were in good agreement with the experimental results. The optimization results also showed that high selectivity for phenol was achieved at the optimized values of the operating variables: reaction temperature 324 K, reaction time 8 h, H2O2 content 3.28 mL, and catalyst dosage 0.09 g. This study showed that RSM was a reliable method for optimizing process variables for benzene hydroxylation to phenol. 展开更多
关键词 mesoporous silica Chromium/SBA-16 catalyst Benzene hydroxylation Phenol Response surface methodology
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Improved Ti-containing Mesoporous Silica Catalyst Synthesized by Using Anionic Surfactant as Co-template
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作者 Wang Jingjing Teng Hongni +3 位作者 Xiao Wei Wang Jinqu Lu Jinming Yang Jianhua 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2016年第3期41-48,共8页
Ti-containing mesoporous silica materials(Ti-MSs) with isolated tetrahedrally coordinated Ti species have been widely applied in bulk molecular catalysis. Herein, Ti-MSs were synthesized using anionic surfactant SDS a... Ti-containing mesoporous silica materials(Ti-MSs) with isolated tetrahedrally coordinated Ti species have been widely applied in bulk molecular catalysis. Herein, Ti-MSs were synthesized using anionic surfactant SDS as the co-template. The SDS molecular assembled structures can interact with silica species through the interface hydrogen bonds leading to the formation of mesoporous silica structure with compact Ti-O bonds, lower hydrophilicity and low template cost. The influence of adding SDS as the co-template on the oxidation of styrene with aqueous H_2O_2 as the oxidant was investigated. Ti-MSs using SDS as the co-template showed better catalytic performance as compared with mesoporous titanium silicate synthesized with CTAB serving as the sole template. Moreover, the Ti-MSs synthesized at a Ti/Si ratio of 0.005 demonstrated an optimized performance for styrene oxidation with styrene conversion improved by 14.8%, benzaldehyde selectivity improved by 13.7% and styrene oxide selectivity improved by 9.2% when the reaction time was 6 h. 展开更多
关键词 sol-gel preparation mesoporous titanium silicate structure ANIONIC surfactant co-template OLEFIN oxidation green catalyst
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Wormholelike mesoporous carbon supported Pt Ru catalysts toward methanol electrooxidation 被引量:1
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作者 Weifeng Liu Xiaoping Qin +2 位作者 Xiongfu Zhang Zhigang Shao Baolian Yi 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第1期200-206,共7页
Wormholelike mesoporous carbons (WMCs) with three different pore diameters (D-P), namely WMC-F7 (D-p = 8.5 nm), WMC-F30 (D-p =4.4 nm), and WMC-F0 (D-p =3.1 nm) are prepared via a modified sol-gel process. Then PtRu na... Wormholelike mesoporous carbons (WMCs) with three different pore diameters (D-P), namely WMC-F7 (D-p = 8.5 nm), WMC-F30 (D-p =4.4 nm), and WMC-F0 (D-p =3.1 nm) are prepared via a modified sol-gel process. Then PtRu nanoparticles with the particle size (40 of 3.2 nm supported on WMCs are synthesized with a modified pulse microwave-assisted polyol method. It is found that the pore diameter of WMCs plays an important role in the electrochemical activity of PtRu toward alcohol electrooxidation reaction. PtRu/WMC-F7 with D-p > 2d(pt) exhibits the largest electrochemical surface area (ESA) and the highest activity toward methanol electrooxidation. With the decrease in Dp, PtRu/WMC-F30 and PtRu/WMC-F0 have much lower ESA and electrochemical activity, especially for the isopropanol electrooxidation with a larger molecular size. When D-p is more than twice d(pt), the mass transfer of reactants and electrolyte are easier, and thus more PtRu nanoparticles can be utilized and the catalysts activity can be enhanced. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved. 展开更多
关键词 Wormholelike mesoporous carbon PtRu catalyst Pore diameter Methanol electrooxidation
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An Experimental Study of the Performance of Isomorphically Zirconium-Substituted Mesoporous Alumina Supported Cobalt Catalysts in Fischer-Tropsch Synthesis
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作者 Sabar Simanungkalit Mingming Zhu +2 位作者 Gia Hung Pham Zhezi Zhang Dongke Zhang 《Advances in Chemical Engineering and Science》 2022年第1期40-53,共14页
A series of mesoporous alumina (MA) supported cobalt (Co/MA) catalysts with MA isomorphically substituted by zirconium (Zr) were synthesised and evaluated for their performance in the Fischer</span><span styl... A series of mesoporous alumina (MA) supported cobalt (Co/MA) catalysts with MA isomorphically substituted by zirconium (Zr) were synthesised and evaluated for their performance in the Fischer</span><span style="font-family:Verdana;">-</span><span style="font-family:""><span style="font-family:Verdana;">Tropsch synthesis. The Zr/(Zr + Al) atomic ratios varied from 1% - 15%. A zirconium-impregnated Co/MA catalyst prepared by wet impregnation with a Zr/(Zr + Al) atomic ratio of 5% was also evaluated to examine Zr incorporation’s effect method. The catalysts synthesised were characterised using N</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> adsorption-desorption, X-ray Powder Diffraction (XRD), Transmission Electron Microscopy (TEM), and X-Ray Photoelectron Spectroscopy (XPS). It was found that Zr</span><sup><span style="font-family:Verdana;">4+</span></sup><span style="font-family:Verdana;"> ions were incorporated into the framework of MA and kept intact up to a Zr/(Zr + Al) atomic ratio of 5%. The cobalt dispersion and reducibility were improved as the Zr/(Zr + Al) atomic ratio increased to 50%. The performance of these catalysts for Fischer</span></span><span style="font-family:Verdana;">-</span><span style="font-family:""><span style="font-family:Verdana;">Tropsch synthesis was evaluated using a fixed bed reactor at temperature and pressure of 493 K and 20 bar, respectively. The feed syngas </span><span><span style="font-family:Verdana;">had an H</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">/CO ratio of 2, diluted with 10% Ar. For isomorphically</span></span><span style="font-family:Verdana;"> Zr-substituted Co/MA, the CO conversion and selectivity of diesel (C</span><sub><span style="font-family:Verdana;">10</span></sub><span style="font-family:Verdana;"> - C</span><sub><span style="font-family:Verdana;">20</span></sub><span style="font-family:Verdana;">) increased first and then decreased with increasing the Zr/(Zr + Al) atomic ratio. The maximum 38.9% CO conversion and 34.6% diesel (C</span><sub><span style="font-family:Verdana;">10</span></sub><span style="font-family:Verdana;"> - C</span><sub><span style="font-family:Verdana;">20</span></sub><span style="font-family:Verdana;">) selectivity were obtained at Zr/(Zr + Al) atomic ratio of 5%. The isomorphic substitution method was better than the wet impregnation method in CO conversion and diesel selectivity. 展开更多
关键词 Cobalt catalyst Fischer-Tropsch Synthesis Isomorphic Substitution mesoporous Alumina ZIRCONIUM
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Facile preparation of bi-functional iron doped mesoporous materials and their application in the cycloaddition of CO2 被引量:3
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作者 Dan Liu Gang Li +1 位作者 Hongchen Guo Jiaxu Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第2期52-59,共8页
Two kinds of bi-functional transition metal doped mesoporous materials(Fe-HMS and Fe-MCM-41) are prepared using one-step hydrothermal method and then treated with hydrochloric acid ethanol solution.The N2 adsorption a... Two kinds of bi-functional transition metal doped mesoporous materials(Fe-HMS and Fe-MCM-41) are prepared using one-step hydrothermal method and then treated with hydrochloric acid ethanol solution.The N2 adsorption and HRTEM results show that both of Fe-HMS and Fe-MCM-41 possess mesoporous structure. The UV–vis results suggest that the Fe species are mainly located within the framework. The basicity of as-prepared samples was studied by temperature programmed desorption using CO2 as probe molecule(CO2-TPD). The catalytic performance of Fe-HMS and Fe-MCM-41 in CO2 cycloaddition largely depends on the amount of the accessible basic sites. The acid–base active sites, framework Fe and PDDA species cooperatively catalyze the CO2 cycloaddition for the production of cyclic carbonates under the condition without any co-catalyst. The conversion of epichlorohydrin(ECH) is 97.4% and the selectivity of chloropropene carbonate is 92.9% under optimal conditions. The approximate rate constant of cycloaddition reaction of CO2 with ECH under optimum reaction temperature is calculated. It is worth noting that the Fe-HMS material shows superior reusability than Fe-MCM-41. In addition, this work provides a facile way on the synthesis of bi-functional acid–base heterogeneous catalyst with outstanding catalytic performance for the fixation of CO2. 展开更多
关键词 mesoporous material CATIONIC polymers ACID-BASE catalyst CYCLOADDITION reaction Cyclic CARBONATE
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N‑Doped Graphene‑Decorated NiCo Alloy Coupled with Mesoporous NiCoMoO Nano‑sheet Heterojunction for Enhanced Water Electrolysis Activity at High Current Density 被引量:13
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作者 Guangfu Qian Jinli Chen +2 位作者 Tianqi Yu Lin Luo Shibin Yin 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第5期77-89,共13页
Developing highly effective and stable non-noble metalbased bifunctional catalyst working at high current density is an urgent issue for water electrolysis(WE).Herein,we prepare the N-doped graphene-decorated NiCo all... Developing highly effective and stable non-noble metalbased bifunctional catalyst working at high current density is an urgent issue for water electrolysis(WE).Herein,we prepare the N-doped graphene-decorated NiCo alloy coupled with mesoporous NiCoMoO nano-sheet grown on 3D nickel foam(NiCo@C-NiCoMoO/NF)for water splitting.NiCo@C-NiCoMoO/NF exhibits outstanding activity with low overpotentials for hydrogen and oxygen evolution reaction(HER:39/266 mV;OER:260/390 mV)at±10 and±1000 mA cm^(−2).More importantly,in 6.0 M KOH solution at 60℃ for WE,it only requires 1.90 V to reach 1000 mA cm−2 and shows excellent stability for 43 h,exhibiting the potential for actual application.The good performance can be assigned to N-doped graphene-decorated NiCo alloy and mesoporous NiCoMoO nano-sheet,which not only increase the intrinsic activity and expose abundant catalytic activity sites,but also enhance its chemical and mechanical stability.This work thus could provide a promising material for industrial hydrogen production. 展开更多
关键词 N-doped graphene-decorated NiCo alloy catalyst mesoporous nano-sheet Water electrolysis High current density
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Mesoporous Silicoaluminum Pillared Clays with High Thermal Stability and BrФnsted/Lewis Acidity by One-pot Synthesis 被引量:3
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作者 ChunHuiZHOU XiaoNianLI DongShengTONG YiFenZHU ZhongHuaGE 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第2期261-264,共4页
Mesoporous silicoaluminum pillared clays have been synthesized by one-potgallery-templated synthesis using organomontmorillonite, tetraethyl orthosilicate and aluminaisopropoxide as precursor. According to the charact... Mesoporous silicoaluminum pillared clays have been synthesized by one-potgallery-templated synthesis using organomontmorillonite, tetraethyl orthosilicate and aluminaisopropoxide as precursor. According to the characterization by powder X-ray diffraction(PXRD), thermogravimetric analysis (TGA), N2 adsorption isotherms and pyridine adsorptioninfrared (IR) techniques, the synthetic silicoaluminum pillared clays possess regular porosity withhigh thermal stability up to 750 ℃ and Br?nsted /Lewis acidity. 展开更多
关键词 Pillared clays mesoporous materials ACIDITY solid acid catalysts.
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Hierarchically mesoporous carbon spheres coated with a single atomic Fe-N-C layer for balancing activity and mass transfer in fuel cells 被引量:11
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作者 Chengyong Shu Qiang Tan +9 位作者 Chengwei Deng Wei Du Zhuofan Gan Yan Liu Chao Fan Hui Jin Wei Tang Xiao-dong Yang Xiaohua Yang Yuping Wu 《Carbon Energy》 SCIE CAS 2022年第1期1-11,共11页
Novel cost-effective fuel cells have become more attractive due to the demands for rare and expensive platinum-group metal(PGM)catalysts for mitigating the sluggish kinetics of the oxygen reduction reaction(ORR).The h... Novel cost-effective fuel cells have become more attractive due to the demands for rare and expensive platinum-group metal(PGM)catalysts for mitigating the sluggish kinetics of the oxygen reduction reaction(ORR).The high-cost PGM catalyst in fuel cells can be replaced by earth-abundant transition-metalbased catalysts,that is,an Fe-N-C catalyst,which is considered one of the most promising alternatives.However,the performance of the Fe-N-C catalyst is hindered by the low catalytic activity and poor stability,which is caused by insufficient active sites and the lack of optimization of the triple-phase interface for mass transportation.Herein,a novel Fe–N–C catalyst consisting of mono-dispersed hierarchically mesoporous carbon sphere cores and single Fe atom-dispersed functional shells are presented.The synergistic effect between highly dispersed Fe-active sites and well-organized porous structures yields the combination of high ORR activity and high mass transfer performance.The half-wave potential of the catalyst in 0.1M H_(2)SO_(4) is 0.82 V versus reversible hydrogen electrode,and the peak power density is 812 mW·cm^(−2) in H_(2)–O_(2) fuel cells.Furthermore,it shows superior methanol tolerance,which is almost immune to methanol poisoning and generates up to 162 mW·cm^(−2) power density in direct methanol fuel cells. 展开更多
关键词 fuel cell hierarchically mesoporous carbon spheres oxygen reduction reaction single‐atom catalysts
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Catalytic performance enhancement by alloying Pd with Pt on ordered mesoporous manganese oxide for methane combustion 被引量:7
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作者 Peng Xu Zhixing Wu +4 位作者 Jiguang Deng Yuxi Liu Shaohua Xie Guangsheng Guo Hongxing Dai 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第1期92-105,共14页
Ordered mesoporous Mn2O3 (meso‐Mn2O3) and meso‐Mn2O3‐supported Pd, Pt, and Pd‐Pt alloy x(PdyPt)/meso‐Mn2O3; x = (0.10?1.50) wt%; Pd/Pt molar ratio (y) = 4.9?5.1 nanocatalysts were prepared using KIT‐6‐templated... Ordered mesoporous Mn2O3 (meso‐Mn2O3) and meso‐Mn2O3‐supported Pd, Pt, and Pd‐Pt alloy x(PdyPt)/meso‐Mn2O3; x = (0.10?1.50) wt%; Pd/Pt molar ratio (y) = 4.9?5.1 nanocatalysts were prepared using KIT‐6‐templated and poly(vinyl alcohol)‐protected reduction methods, respectively.The meso‐Mn2O3 had a high surface area, i.e., 106 m2/g, and a cubic crystal structure. Noble‐metalnanoparticles (NPs) of size 2.1?2.8 nm were uniformly dispersed on the meso‐Mn2O3 surfaces. AlloyingPd with Pt enhanced the catalytic activity in methane combustion; 1.41(Pd5.1Pt)/meso‐Mn2O3gave the best performance; T10%, T50%, and T90% (the temperatures required for achieving methaneconversions of 10%, 50%, and 90%) were 265, 345, and 425 °C, respectively, at a space velocity of20000 mL/(g?h). The effects of SO2, CO2, H2O, and NO on methane combustion over1.41(Pd5.1Pt)/meso‐Mn2O3 were also examined. We conclude that the good catalytic performance of1.41(Pd5.1Pt)/meso‐Mn2O3 is associated with its high‐quality porous structure, high adsorbed oxygen species concentration, good low‐temperature reducibility, and strong interactions between Pd‐Pt alloy NPs and the meso‐Mn2O3 support. 展开更多
关键词 Ordered mesoporous manganese oxide Pd‐Pt alloy nanoparticle Supported noble metal catalyst Strong metal‐support interaction Methane combustion
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Synthesis and Characterization of Novel Layered Lithium Sodium Silicate (Silinaite) and the Mesoporous Materials from Silinaite 被引量:1
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作者 Chun Hui ZHOU Hong Qiang GUO Hui Jun CAO Xiao Nian LI Zhong Hua GE Jie LI 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第4期525-528,共4页
Novel layered silinaite has been synthesized using an aqueous mixture of water glass, LiOH and NaOH under hydrothermal crystallization. Subsequently transformation of silinaite into mesoporous materials (SDM) was ac... Novel layered silinaite has been synthesized using an aqueous mixture of water glass, LiOH and NaOH under hydrothermal crystallization. Subsequently transformation of silinaite into mesoporous materials (SDM) was achieved at mild condition using cetyltfimethylammonium bromide as structure-directing agents. The resulting samples were characterized by XRD, SEM, FTIR nitrogen adsorption-desorption isotherms and catalytic performance in bulky molecular involved reaction. The results revealed that synthesized mesoporous materials derived from the silinaite exhibited an ordered hexagonal crystal structure with average pore diameter 2.7 nm and BET surface area 817m^2/g. The SDM-supported ZnCl2 catalyst, prepared by impregnationevaporation method, retained the mesoporous structure and showed high selectivity in alkylation of benzene with benzyl chloride. 展开更多
关键词 Silinaite mesoporous materials layered solid catalystS characterization.
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