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Enhanced bifunctional oxygen electrochemical catalytic performance using La-doped CoFe_(2)O_(4)spinel supported by 3D-G for Zn-air batteries
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作者 Yinggang Sun Tingwei Zhang +5 位作者 Peng Sun Jigang Wang Wenjie Duan Yanqiong Zhuang Likai Wang Zhongfang Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期778-788,共11页
The preparation of bifunctional catalysts for oxygen reduction(ORR)and oxygen evolution(OER)is crucial for Zn-air batteries.Here,we report a La doped CoFe_(2)O_(4) spinel catalyst supported on threedimensional graphen... The preparation of bifunctional catalysts for oxygen reduction(ORR)and oxygen evolution(OER)is crucial for Zn-air batteries.Here,we report a La doped CoFe_(2)O_(4) spinel catalyst supported on threedimensional graphene(3D-G),where La can facilitate electron transfer from Co to Fe,leading to increased electron cloud density in Fe and improved catalytic performance.The redshift of the G peak in the Raman spectra indicates the interaction between theπbond of 3D-G and d orbitals in La_(0.2)CoFe_(1.8)O_(4).La_(0.2)CoFe_(1.8)/3D-G exhibits superior ORR performance(E_(1/2)=0.86 V vs.RHE)and OER performance(E_(j=10)=1.55 V vs.RHE)to CoFe_(2)O_(4)/3D-G(E_(1/2)=0.831 V vs.RHE,E_(j=10)=1.603 V vs.RHE).Furthermore,it demonstrates excellent bifunctional oxygen catalytic performance while maintaining high power density and stability in liquid zinc-air batteries(ZABs)and flexible ZABs(F-ZABs).This work presents a viable strategy for utilizing rare earth element doped spinels to enhance oxygen catalyst and ZABs performance. 展开更多
关键词 Zn-air batteries Electrocatalysts La_(0.2)CoFe_(1.8)/3D-G Electron pump Bifunctional oxygen catalytic performance
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Preparation of Zn-modified nano-ZSM-5 zeolite and its catalytic performance in aromatization of 1-hexene 被引量:6
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作者 王高亮 吴伟 +4 位作者 昝望 白雪峰 王文静 戚鑫 O.V.KIKHTYANIN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第5期1580-1586,共7页
The promoting effect of introducing Zn into nano-ZSM-5 zeolites by conventional impregnation method and isomorphous substitution on the performance of 1-hexene aromatization was investigated. The nano-ZSM-5 zeolite wa... The promoting effect of introducing Zn into nano-ZSM-5 zeolites by conventional impregnation method and isomorphous substitution on the performance of 1-hexene aromatization was investigated. The nano-ZSM-5 zeolite was synthesized by a seed-induced method without organic templates. The Zn-modified nano-ZSM-5 zeolite catalysts, xZ n/HNZ5 and y Zn/Al-HNZ5, were prepared by the conventional impregnation method and isomorphous substitution, respectively. The structure, chemical composition and acidity of the catalysts were characterized by XRD, XRF, N2 adsorption, SEM, NH3-TPD and Py-IR, while the catalytic properties were evaluated at 480 °C and a weight hourly space velocity(WHSV) of 2.0 h-1 in the aromatization procedure of 1-hexene. Compared with xZ n/HNZ5, y Zn/Al-HNZ5 exhibited smaller particles and higher dispersion of Zn species, which led to greater intergranular mesopore and homogeneous acidity distribution. Experimental results indicated that the synergy effect between the Brnsted and Lewis acid sites of the isomorphously substituted nano-ZSM-5 zeolites could significantly increase aromatics yield and improve catalytic stability in the 1-hexene aromatization. 展开更多
关键词 nano-ZSM-5 zeolite Zn-modification catalytic performance isomorphous substitution AROMATIZATION
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Effects of sol-gel method and lanthanum addition on catalytic performances of nickel-based catalysts for methane reforming with carbon dioxide 被引量:4
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作者 黎先财 胡全红 +2 位作者 杨沂凤 陈娟荣 赖志华 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第6期864-868,共5页
The nickel-based catalysts were prepared by the sol-gel method and used for the CH4 reforming with CO2. The effects of the sol-gel method on the specific surface area, catalytic activity, desorption, and reduction per... The nickel-based catalysts were prepared by the sol-gel method and used for the CH4 reforming with CO2. The effects of the sol-gel method on the specific surface area, catalytic activity, desorption, and reduction performances of catalysts were investigated with BET, TPR, and TPD. Compared with the catalyst prepared by the impregnation method, the results indicated that the catalysts prepared by the sol-gel method had larger specific surface area, showing higher catalytic activities and exhibiting perfect desorption and reduction performances. In addition, the modification effects of adding La were studied, and it was found that the 0.75NLBT catalyst constituted of 5wt.%Ni-0.75wt.%La was optimal. 展开更多
关键词 sol-gel method nickel-based catalyst REFORMING catalytic performance rare earths
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Catalytic Performance of MnO_x-WO_3/TiO_2 Catalyst for Selective Catalytic Reduction of NO_x with NH_3 and Its Tolerance Towards SO_2 被引量:3
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作者 WU Bi-jun LIU Xiao-qin XIAO Ping 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第6期914-919,共6页
The performance of Mn-W/TiO2 for selective catalytic reduction(SCR) of NOx with NH3 and its resistance to different concentrations of SO2 at various temperatures were investigated. The results show that WO3 increase... The performance of Mn-W/TiO2 for selective catalytic reduction(SCR) of NOx with NH3 and its resistance to different concentrations of SO2 at various temperatures were investigated. The results show that WO3 increased the active sites and enhanced the strength of acid, so it was an effective promoter of MnOJTiO2. The NOx conversion on Mn-W/TiO2 ranges from 80.3% to 99.6% between 100 ℃to 350℃ at GHSV=18900 h 1, while N2 product selectivity changes from 100% to 98.7%. In the presence of 0.01% SO2 and 6% H20, NOx conversion maintained 98.5% at 120℃. The influence of more than 0.01% SO2 on the activity of MnOx-WO3/TiO2 will disappear if the temperature rises above 250℃. By means of heating and sweeping with He, the activity of the catalysts can be recovered. At 300℃, NOx conversion yielded 99% with 0.07% SO2 and reached the level of commercial V-W/TiO2 catalysts. The Mn-W/TiO2 catalyst showed excellent performance for SCR of NOx with NH3 in a wider range of temperature with strong tolerance to SO2. 展开更多
关键词 Selective catalytic reduction NOx MnOx-WO3/TiO2 catalytic performance
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Ru effect on the catalytic performance of Pd@Ru/C catalysts for methanol electro-oxidation 被引量:2
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作者 Yanbiao Ren Shichao Zhang Xin Wei 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第2期232-238,共7页
Pd@Ru bimetallic nanoparticles deposited on carbon black electro-catalysts have been fabricated by microwave-assisted polyol reduction method and investigated for methanol electro-oxidation (MEO). The structure and ... Pd@Ru bimetallic nanoparticles deposited on carbon black electro-catalysts have been fabricated by microwave-assisted polyol reduction method and investigated for methanol electro-oxidation (MEO). The structure and electro-catalytic properties of the as-prepared catalysts were characterized by XRD, SEM, TEM and cyclic voltammetry (CV) techniques. The results showed that the introduction of Ru element (2-10 wt%) into Pd 20 wt%/C (hereafter, denoted as Pd/C) produced a series of core-shell structured binary catalysts. Pd@Ru 5 wt%/C (hereafter, denoted as Pd@Rus/C) catalyst displayed the highest catalytic activity towards MEO. And the mass activity of Pd@Ru5/C electrode catalyst at E = -0.038 V (vs. Hg/HgO) was 1.42 times higher than that of Pd/C electrode catalyst. In addition, the relationship between the catalytic stability for MEO on Pd@Ru/C catalysts and the value of dbp/dfp (the ratio of MEO peak current density in the negative scan and positive scan) were also investigated. The result demonstrated that Pd@Rus/C offering the smallest value of Jbp/Jfp displayed the best stable catalytic performance. 展开更多
关键词 methanol electro-oxidation catalytic performance poisoning tolerance core-shell structured catalyst
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Synthesis,characterization and catalytic performance of nanosized iron-cobalt catalysts for light olefins production 被引量:1
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作者 Mostafa Feyzi Asadollah Hassankhani 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2011年第6期677-686,共10页
Nanosized Fe-Co catalysts were prepared by co-precipitation method and studied for the conversion of synthesis gas to light olefins.In particular,the effects of a range of preparation variables such as Co/Fe molar rat... Nanosized Fe-Co catalysts were prepared by co-precipitation method and studied for the conversion of synthesis gas to light olefins.In particular,the effects of a range of preparation variables such as Co/Fe molar ratios of the precipitation solution,pH value of precipitate,temperature of precipitation,promoters and loading of optimum promoter on the structure and catalytic performance are investigated.The optimal nano catalyst for light olefins (C2-C4) production was obtained over the catalyst with Co/Fe molar ratio of 3/1 which promoted with 2 wt% K.The results show that the best operational conditions were GHSV=2200 h^-1 (H2/CO=2/1) at 260℃ under atmospheric pressure.Characterization of catalysts were carried out using X-ray diffraction (XRD),thermal gravimetric analysis (TGA),differential scanning calorimetry (DSC),scanning electron microscopy (SEM),transmission electron microscopy (TEM) and N2 physisorption measurements such as Brunauer-Emmett-Teller (BET) and Barrett-Joyner-Halenda (BJH) methods. 展开更多
关键词 light olefins catalytic performance operational condition CHARACTERIZATION
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Effects of Operating Conditions on the Catalytic Performance of HZSM-5 Zeolites in n-Pentane Cracking 被引量:1
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作者 Hou Xu Zhao Liu +3 位作者 Ma Zhenzhou Chen Bochong Feng Jingyuan Cui Tingting 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2021年第1期67-75,共9页
In this work,n-pentane catalytic cracking over HZSM-5 zeolites was studied at 650°C under atmosphere pressure.A particular attention was paid to the measurement of n-pentane conversion,light olefins production,pr... In this work,n-pentane catalytic cracking over HZSM-5 zeolites was studied at 650°C under atmosphere pressure.A particular attention was paid to the measurement of n-pentane conversion,light olefins production,product distribution,coke deposit,etc.Several indexes were defined to evaluate the effects of operating conditions on the catalytic performance of HZSM-5 zeolites.It was found that decreasing the weight hourly space velocity,increasing the reactant partial pressure,and increasing the carrier gas flow rate could inhibit C-H bond breaking and enhance the C-C bond breaking and hydride transfer reactions,leading to reduced alkenes selectivity,which suppressed the formation of external coke and alleviated the deactivation of HZSM-5 zeolites.It was deduced that the catalytic stability of HZSM-5 zeolites was improved at the cost of alkenes selectivity.Compared with decreasing the weight hourly space velocity and increasing the reactant partial pressure,increasing the carrier gas flow rate could enhance the diffusion process and protect alkenes from being consumed in coke formation in order to improve the catalytic stability of HZSM-5 zeolites with less reduction of alkenes selectivity. 展开更多
关键词 operating conditions HZSM-5 zeolites catalytic performance n-pentane cracking light olefins
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Direct Synthesis,Characterization and Catalytic Performance of Iron-Containing SBA-15 for Phenol Degradation
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作者 谢焕玲 徐文国 《Journal of Beijing Institute of Technology》 EI CAS 2008年第2期232-236,共5页
An iron-containing SBA-15(Fe-SBA-15) has been synthesized via one-pot hydrothermal method under weak acidic conditions. A series of characterizations show nanocomposite materials of iron particles supported over mes... An iron-containing SBA-15(Fe-SBA-15) has been synthesized via one-pot hydrothermal method under weak acidic conditions. A series of characterizations show nanocomposite materials of iron particles supported over mesostructured materials. The catalytic activity of these iron-containing SBA-15 materials has been tested for the heterogeneous Fenton degradation of phenolic aqueous solutions. The catalytic performance has beta monitored in terms of phenol conversion, whereas the catalytic stability was evaluated by catalyst recycle. The influence of concentration of hydrogen peroxide, catalyst loading, catalyst prepared with different Fe/Si molar ratios in the gel and pH values of the solution on phenol conversion has been studied. Achieving a good catalytic performance accompanied with a noteworthy stability, Fe-SBA-15 materials prepared by this method are shown as the successful catalyst for degradation of phenolic aqueous solutions by Fenton process. 展开更多
关键词 Fe-SBA-15 Fenton reagent PHENOL catalytic performance catalytic stability
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The regulating effect of doping Cu on the catalytic performance of CO oxidative coupling to DMO on Pd_(x)Cu_(y)/GDY:A DFT study
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作者 Juan Zhao Min Han +3 位作者 Zhanhui Wang Lixia Ling Riguang Zhang Baojun Wang 《Green Energy & Environment》 SCIE EI CSCD 2022年第4期742-754,共13页
Rely on the density functional theory(DFT)calculation,the catalytic performance of Pd_(x)Cu_(y)/GDY(x=1,2,3,4;x+y≤4)for CO oxidative coupling reaction was obtained.The Pdx/GDY(x=1,2,3,4)are not ideal catalyst for dim... Rely on the density functional theory(DFT)calculation,the catalytic performance of Pd_(x)Cu_(y)/GDY(x=1,2,3,4;x+y≤4)for CO oxidative coupling reaction was obtained.The Pdx/GDY(x=1,2,3,4)are not ideal catalyst for dimethyl oxalate(DMO)formation because byproduct dimethyl carbonate(DMC)is easily formed on Pd_(1)/GDY and Pd_(2)/GDY,and high activation energies are needed on Pd_(3)/GDY and Pd_(4)/GDY.Therefore the second metal Cu is doped to regulate the performance of Pdx/GDY(x=1,2,3,4).Doping Cu not only improve the activity of DMO formation,but more importantly,controlling the ratio of Cu:Pd can effectively regulate the selectivity of DMO.Thus taking into account the activity and selectivity of the reaction for the preparation of DMO by CO oxidative coupling,the Pd_(1)Cu_(1)/GDY and Pd_(1)Cu_(2)/GDY with the activation energies of 105.2 and 99.2 kJ mol^(-1)to generate DMO show excellent catalytic activity and high DMO selectivity,which are considered as good catalysts for CO oxidative coupling.The differential charge density analysis shows the decrease in the charge density of metal clusters is an important reason for improving the selectivity of the catalyst. 展开更多
关键词 GDY Pd clusters Cu:Pd ratio DMO formation catalytic performance
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Pore Structure and Catalytic Performance of Steam-Dealuminated ZSM-5/Y Composite Zeolites
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作者 GuoJintao ShenBaojian ChenHonglin 《Petroleum Science》 SCIE CAS CSCD 2005年第1期62-65,共4页
For investigating the effect of dealumination on the pore structure and catalytic performance, ZSM-5/Y composite zeolites synthesized in situ from NaY gel were dealuminated by steaming at different temperatures. XRD ... For investigating the effect of dealumination on the pore structure and catalytic performance, ZSM-5/Y composite zeolites synthesized in situ from NaY gel were dealuminated by steaming at different temperatures. XRD (X-ray diffraction) characterization indicates that the relative crystallinity of the composite zeolites decreases with the increase in Si/Al ratio after steaming. N2 adsorption-desorption suggests that more mesopores are formed while the BET (Brunauer, Emmett and Teller) specific surface area and the micropore specific surface area decrease as the temperature of steaming rises. Daqing heavy oil was used as feedstock to test the catalytic cracking activity of ZSM-5/Y composite zeolites. The experimental results of the catalytic cracking performance reveal that the distribution of products differs due to the different conditions of hydrothermal treatment. Further hydrothermal treatment leads to an increase in the yield of light oil, and a decrease in the yield of gas products and coke. 展开更多
关键词 ZSM-5/Y composite zeolites steam treatment pore structure catalytic performance
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Preparation and Catalytic Performance of Microporous Polymer/Au Nanoparticles Composite Microspheres
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作者 GUO Chun ZHANG Lijuan +3 位作者 ZHAO Yan LI Mengyuan WANG Xiaotao ZHANG Gaowen 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2020年第2期464-468,共5页
Polystyrene crosslinked microspheres were prepared by soap-free emulsion polymerization using styrene (St) and divinylbenzene (DVB) as monomers;then,the microporous structure was knitted by the Friedel-Crafts alkylati... Polystyrene crosslinked microspheres were prepared by soap-free emulsion polymerization using styrene (St) and divinylbenzene (DVB) as monomers;then,the microporous structure was knitted by the Friedel-Crafts alkylation reaction,and the Au nanoparticles (AuNPs) were loaded into the pores through thermal reduction,to obtain AuNPs/ hyper-crosslinked microporous polymer composite microspheres.SEM and particle-size test results show that the microspheres show good monodispersity.The micropore analysis indicates that the specific surface area and the pore volume of the microporous polymer microspheres decrease with increasing DVB content,and when the DVB content is 0.1%,the specific surface area reaches a maximum of 1 174.6 m2/g.After loading AuNPs,the specific surface area and the amount of micropores of the composite microspheres decrease obviously.The results of XRD and XPS analyses suggest that HAuCl4 is reduced to AuNPs.The composite microspheres show a good catalytic performance for the reduction catalyst of 4-nitrophenol. 展开更多
关键词 microporous polystyrene microspheres Au nanoparticles hyper-crosslinking catalytic performance
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CATALYTIC PERFORMANCE OF ETHYLENE HYDROFORMYLATION OVER[H_XRu_3(CO)_9(CCO)]^(2-X)/SiO_2-Al_2O_3,SiO_2 AND MgO(X=0-2)CATALYSTS
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作者 Feng Shou XIAO RuRen XU (Department of Chemistry,Jilin University,Changchun 130023)Masaru ICHIKAWA (Catalysis Research Center,Hokkaido University,Sapporo 060,Japan)Duward F.SHRIVER (Department of Chemistry,Northwestern University,Evanston,IL 602083113,USA)Xie Xian GUO (National Laboratory for Catalysis,Dalian Institute of Chemical Physics,Chinese Academy of Sciences,Dilian 116023,) 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第7期579-580,共2页
The various surface species[H_XRu_3(CO)_9(CCO)]^(2-X)(X=0-2)prepared from impregnation of[PPN]_2[Ru_3(CO)_9(CCO)]on SiO_2-Al_2O_3,SiO_2 and MgO show quite different activities and selectivities for oxygenates and etha... The various surface species[H_XRu_3(CO)_9(CCO)]^(2-X)(X=0-2)prepared from impregnation of[PPN]_2[Ru_3(CO)_9(CCO)]on SiO_2-Al_2O_3,SiO_2 and MgO show quite different activities and selectivities for oxygenates and ethane in ethylene hydroformylation. 展开更多
关键词 CCO X=0-2)CATALYSTS catalytic performance OF ETHYLENE HYDROFORMYLATION OVER[HXRu3 X SiO2-Al2O3 SiO2 AND MgO MGO Al
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CATALYTIC PERFORMANCE OF MIXED-BIMETALLIC RUTHENIUM CARBONYL CLUSTERDERIVED CATALYSTS IN CO HYDROGENATION
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作者 Masaru ICHIKAWA Atsushi FUKUOKA Catalysis Research Center,Hokkaido University,Sapporo 060,Japan. Feng Shou XIAO Catalysis Research Center,Hokkaido University,Sapporo 060,Japan.Department of Chemistry,Jilin University,Changchun 120023,China. D.F.SHRIVER Department of Chemistry,Northwestern University,Evanston,IL 602083113,USA. 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第9期707-708,共2页
The bimetallic catalysts prepared from SiO_2-supported Ru-Co,Ru- Fe and Ru-Mo carbonyl clusters exhibited high yields and selectivities towards oxygenates such as C_1-C_5 from CO+H_2,in contrast to the catalysts prepa... The bimetallic catalysts prepared from SiO_2-supported Ru-Co,Ru- Fe and Ru-Mo carbonyl clusters exhibited high yields and selectivities towards oxygenates such as C_1-C_5 from CO+H_2,in contrast to the catalysts prepared from homometallic and bimetallic Ru,Ru-Ni,Ru-Rh,Ru-Mn,and Ru- Cr carbonyl clusters.The FTIR investigation revealed that the 1584 cm^(-1) species plays an important role in the formation of oxygenates in CO hydrogenation,which is possibly assigned to surface formyl species. 展开更多
关键词 Ru CO Cr catalytic performance OF MIXED-BIMETALLIC RUTHENIUM CARBONYL CLUSTERDERIVED CATALYSTS IN CO HYDROGENATION CO
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THE RELATIONSHIPS BETWEEN THE POLARIZING FORCE OF CATIONS AND THE ELECTROPHILIC CHARACTER AND CATALYTIC PERFORMANCES OF PROMOTED Pt-Al_2O_3 CATALYST
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作者 Jia LIU Xi Yao YANG Li PANG Department of Chemistry,Peking University,Beijing,100871 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第3期261-262,共2页
The electronic modification effect of various metal oxides over Pt-Al;O;catalyst andthe relationships between the polarizing force of cations(PFC)and the electrophiliccharacter(EC)and catalytic performances(CP)o... The electronic modification effect of various metal oxides over Pt-Al;O;catalyst andthe relationships between the polarizing force of cations(PFC)and the electrophiliccharacter(EC)and catalytic performances(CP)of promoted Pt catalyst have been studiecby competitive hydrogenation reaction method(CHRM)and test reaction,i.e.hydrogena-tion of benzene and hydrogenolysis of cyclopentane. 展开更多
关键词 Pt EC THE RELATIONSHIPS BETWEEN THE POLARIZING FORCE OF CATIONS AND THE ELECTROPHILIC CHARACTER AND catalytic performanceS OF PROMOTED Pt-Al2O3 CATALYST Al
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Promoted catalytic performance of Ag-Mn bimetal catalysts synthesized through reduction route
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作者 Wenkai Hu Tao Guo +6 位作者 Kaiyao Ma Xu Li Wangting Luo Mingzhi Wu Hao Guo Yaxin Zhang Wenfeng Shangguan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第3期358-369,共12页
VOCs can exert great harm to both human and environment,and catalytic oxidation is believed to be an effective technique to eliminate these pollutants.In this paper,Ag-Mn bimetal catalysts with 10 wt.%of silver were s... VOCs can exert great harm to both human and environment,and catalytic oxidation is believed to be an effective technique to eliminate these pollutants.In this paper,Ag-Mn bimetal catalysts with 10 wt.%of silver were synthesized using doping,impregnation,and reduction methods respectively,and then they were applied to the catalytic oxidation of benzene.Through series of characterizations it showed that the loading of silver using reduction method significantly resulted in improved physico-chemical properties of manganese oxides,such as larger surface area and pore volume,higher proportion of surface Mn~(3+)and Mn~(4+),stronger reducibility and more active of surface oxygen species,which were all beneficial to its catalytic activity.As a result,the Ag-Mn catalysts synthesized by reduction method showed a lower T_(90)value(equals to the temperature at which 90%of initial benzene was removed)of 203℃.Besides,both the used and fresh Ag-Mn catalysts synthesized by reduction method showed preferable stability in this research. 展开更多
关键词 Ag-Mn Benzene oxidation catalytic performance Reduction route
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Mesoporous Cu_(3−x)Zn_(x)(BTC)_(2)nanocubes synthesized in deep eutectic solvent and their catalytic performances 被引量:2
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作者 Jingyang Hu Jianling Zhang +11 位作者 Xiuniang Tan Xiuyan Cheng Zhuizhui Su Lixiong Qian Mingzhao Xu Yufei Sha Yanyue Wang Yisen Yang Yunpeng Liu Guang Mo Xueqing Xing Zhonghua Wu 《Nano Research》 SCIE EI CSCD 2023年第3期3703-3708,共6页
To develop high-performance metal-organic frameworks(MOFs)for catalysis is of great importance.Here,we synthesized the mesoporous Cu_(3−x)Zn_(x)(BTC)_(2)(BTC=benzene-1,3,5-tricarboxylate)nanocubes in a deep eutectic s... To develop high-performance metal-organic frameworks(MOFs)for catalysis is of great importance.Here,we synthesized the mesoporous Cu_(3−x)Zn_(x)(BTC)_(2)(BTC=benzene-1,3,5-tricarboxylate)nanocubes in a deep eutectic solvent of ZnCl_(2)/ethylene glycol solution.The route can proceed at room temperature and the reaction time needed is shortened to be 30 min,which is superior to the conventional solvothermal route that usually needs high temperature and long reaction time.The formation mechanism of the mesoporous Cu_(3−x)Zn_(x)(BTC)_(2)nanocubes in deep eutectic solvent(DES)was investigated by in situ synchrotron X-ray diffraction/small angle X-ray scattering/X-ray absorption fine structure conjunction technique.The mesoporous Cu_(3−x)Zn_(x)(BTC)_(2)nanocubes exhibit high catalytic activity and reusability for cyanosilylation reaction of benzaldehyde and aerobic oxidation reaction of benzylic alcohol. 展开更多
关键词 bimetallic metal-organic framework(MOF) mesoporous nanocubes deep eutectic solvent formation mechanism catalytic performance
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Boosting the catalytic activity toward oxygen reduction via a heterostructure of porous iron oxide-decorated 2D NiO/NG nanosheets
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作者 Kakali Maiti Matthew T.Curnan +2 位作者 Hyung Jun Kim Kyeounghak Kim Jeong Woo Han 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期669-681,I0016,共14页
As a noble metal substitute,two-dimensional(2D)hierarchical nano-frame structures have attracted great interest as candidate catalysts due to their remarkable advantages-high intrinsic activity,high electron mobility,... As a noble metal substitute,two-dimensional(2D)hierarchical nano-frame structures have attracted great interest as candidate catalysts due to their remarkable advantages-high intrinsic activity,high electron mobility,and straightforward surface functionalization.Therefore,they may replace Pt-based catalysts in oxygen reduction reaction(ORR)applications.Herein,a simple method is developed to design hierarchical nano-frame structures assembled via 2D NiO and N-doped graphene(NG)nanosheets.This procedure can yield nanostructures that satisfy the criteria correlated with improved electrocatalytic performance,such as large surface area,numerous undercoordinated atoms,and high defect densities.Further,porous NG nanosheet architectures,featuring NiO nanosheets densely coordinated with accessible holey Fe_(2)O_(3) moieties,can enhance mesoporosity and balance hydrophilicity.Such improvements can facilitate charge transport and expose formerly inaccessible reaction sites,maximizing active site density utilization.Density functional theory(DFT)calculations reveal favored O_(2) adsorption and dissociation on Fe_(2)O_(3) hybrid structures when supported by 2D NiO and NG nanomaterials,given 2D materials donated charge to Fe_(2)O_(3) active sites.Our systematic studies reveal that synergistic contributions are responsible for enriching the catalytic activity of Fe_(2)O_(3)@NiO/NG in alkaline media-encompassing internal voids and pores,unique hierarchical support structures,and concentrated N-dopant and bimetallic atomic interactions.Ultimately,this work expands the toolbox for designing and synthesizing highly efficient 2D/2D shelled functional nanomaterials with transition metals,endeavoring to benefit energy conversion and related ORR applications. 展开更多
关键词 N-doped graphene Holey Fe_(2)O_(3)nanocrystals NiO nanosheets High catalytic performance ORR
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Modulating the local coordination environment of single-atom catalysts for enhanced catalytic performance 被引量:104
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作者 Xinyuan Li Hongpan Rong +2 位作者 Jiatao Zhang Dingsheng Wang Yadong Li 《Nano Research》 SCIE EI CAS CSCD 2020年第7期1842-1855,共14页
The local coordination environment of catalysts has been investigated ftor an extended period to obtain enhanced catalytic performance.Especially with the advancement of single-atom catalysts(SACs),research on the coo... The local coordination environment of catalysts has been investigated ftor an extended period to obtain enhanced catalytic performance.Especially with the advancement of single-atom catalysts(SACs),research on the coordination environment has been advanced to the atomic level.The surrounding coordination atoms of central metal atoms play important roles in their catalytic activity,selectivity and stability.In recent years,remarkable improvements of the catalytic performance of SACs have been achieved by the tailoring of coordination atoms,coordination numbers and second-or higher-coordination shells,which provided new opportunities for the further development of SACs.In this review,the characterization of coordination environment,tailoring of the local coordination environment,and their related adjustable catalytic performance will be discussed.We hope this review will provide new insights on further research of SACs. 展开更多
关键词 single-atom catalysts coordination environment catalytic performance energy conversion
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The effect of hydrogen peroxide on properties of Ce0.35Zr0.55La0.055Pr0.045O2 oxides and the catalytic performance usedon Pd supported three-way catalyst 被引量:5
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作者 Qi wang Meisheng Cui +4 位作者 Xiaowei Huang Yongke Hou Mei Yue Qiang Zhong YongqiZhang 《Journal of Rare Earths》 SCIE EI CAS CSCD 2017年第11期1092-1101,共10页
In this study,two series of cerium zirconium mixed oxides CeZrLaPrOwere prepared under traditional co-precipitation and oxidation co-precipitation methods respectively. The physicochemical properties of the samples we... In this study,two series of cerium zirconium mixed oxides CeZrLaPrOwere prepared under traditional co-precipitation and oxidation co-precipitation methods respectively. The physicochemical properties of the samples were compared under these two methods and assessed by XRD,Raman,BET,TEM,HTPR,OSC,XPS and catalysts measurements. The formation of homogeneity phase structure can be facilitated by changing the precipitating properties of Ce3+ under oxidation coprecipitation method, which is helpful to enhance the homogeneity of Ce and Zr at atomic level.What’s more, it is conducive to remove impurities Na~+ and Cl~-by oxidation co-precipitation with hydrogen peroxide. The catalysts activities are related to both the redox properties and the textural properties of mixed oxides. The Pd-only TWCs supported on the CZLP-H-F exhibits better catalytic performance and thermal stability with wider air/fuel ratio operation window, lower light-off and full conversion temperatures of CHand NO. The homogeneity of phase structure for cerium zirconium mixed oxide can be predicted and deduced from detecting the atomic distribution uniformity of its precursor. So this work not only provides insights into the mechanisms for phase segregation of cerium zirconium mixed oxide, but also provides a guidance to improve homogeneity of cerium zirconium mixed oxide by adding additives. 展开更多
关键词 Cerium zirconium mixed oxides CO-PRECIPITATION Hydrogen peroxide catalytic performance
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Improving the performance of metal-organic frameworks for thermo-catalytic CO_(2)conversion:Strategies and perspectives 被引量:4
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作者 Leiduan Hao Qineng Xia +2 位作者 Qiang Zhang Justus Masa Zhenyu Sun 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第11期1903-1920,共18页
Climate change caused by the increasing emission of CO_(2)to the atmosphere has become a global concern.To ameliorate this issue,converting CO_(2)into valuable chemicals is highly desirable,enabling a sustainable low-... Climate change caused by the increasing emission of CO_(2)to the atmosphere has become a global concern.To ameliorate this issue,converting CO_(2)into valuable chemicals is highly desirable,enabling a sustainable low-carbon future.To this end,developing efficient catalytic systems for CO_(2)conversion has sparked intense interests from both academia and industry.Taking advantage of their highly porous structures and unique properties,metal−organic frameworks(MOFs)have shown great potential as heterogeneous catalysts for CO_(2)conversion.Various transformations involving CO_(2)have been accomplished over MOFs-based materials.Here we provide a comprehensive and up-to-date review on recent advances of heterogeneous CO_(2)thermocatalysis using MOFs,highlighting relationships between structures and properties.Special attention is given to the design strategies for improving the catalytic performance of MOFs.Avenues available to enrich the catalytic active sites in MOF structures are stressed and their respective impacts on CO_(2)conversion efficiency are presented.The synergistic effects between each active site within the structure of MOFs and derivatives are discussed.In the end,future perspectives and challenges in CO_(2)conversion by heterogeneous catalysis with MOFs are described. 展开更多
关键词 CO_(2) conversion Metal-organic frameworks catalytic active sites SYNERGY catalytic performance
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