期刊文献+
共找到21篇文章
< 1 2 >
每页显示 20 50 100
离子液体的合成与应用研究进展 被引量:15
1
作者 赵正康 李娟 吕志果 《精细石油化工进展》 CAS 2009年第6期36-41,共6页
离子液体作为环境友好型离子溶剂具有很多分子溶剂不可比拟的独特性能,无色、无臭、不挥发和低蒸汽压;有较长的稳定的温度范围,较好的化学稳定性,可进行阴阳离子的设计,被认为是理想的绿色高效溶剂。本文综述了离子液体的种类、特点、... 离子液体作为环境友好型离子溶剂具有很多分子溶剂不可比拟的独特性能,无色、无臭、不挥发和低蒸汽压;有较长的稳定的温度范围,较好的化学稳定性,可进行阴阳离子的设计,被认为是理想的绿色高效溶剂。本文综述了离子液体的种类、特点、性质、制备方法和在各领域应用的研究进展。 展开更多
关键词 离子液体 绿色溶剂 功能化催化剂 合成 应用
下载PDF
Strategies for engineering metal-organic frameworks as efficient photocatalysts 被引量:12
2
作者 沈丽娟 梁若雯 吴棱 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第12期2071-2088,共18页
Environmental pollution and energy deficiency represent major problems for the sustainability of the modern world. Photocatalysis has recently emerged as an effective and environmentally friendly technique to address ... Environmental pollution and energy deficiency represent major problems for the sustainability of the modern world. Photocatalysis has recently emerged as an effective and environmentally friendly technique to address some of these sustainability issues,although the key to the success of this approach is dependent on the photocatalysts themselves. Based on their attractive physic chemical properties,including their ultrahigh surface areas,homogeneous active sites and tunable functionality,metal-organic frameworks(MOFs) have become interesting platforms for the development of solar energy conversion devices. Furthermore,MOFs have recently been used in a wide variety of applications,including heterogeneous photocatalysis for pollutant degradation,organic transformations,hydrogen production and CO2 reduction. In this review,we have highlighted recent progress towards the application of MOFs in all of these areas. We have collected numerous reported examples of the use of MOFs in these areas,as well as providing some analysis of the key factors influencing the efficiency of these systems. Moreover,we have provided a detailed discussion of new strategies that have been developed for enhancing the photocatalytic activity of MOFs. Finally,we have provided an outlook for this area in terms of the future challenges and potential prospects for MOFs in photocatalysis. 展开更多
关键词 Metal-organic frameworks PHOTOCATALYSIS LIGAND FUNCTIONALIZATION PHOTOSENSITIZATION CO-CATALYST Composite
下载PDF
Effect of Catalyst Properties on Hydrocracking of Pyrolytic Lignin to Liquid Fuel in Supercritical Ethanol 被引量:1
3
作者 姚倩 唐喆 +2 位作者 郭建华 张颖 郭庆祥 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第2期209-216,I0002,共9页
The metal-acid bifunctional catalysts have been used for bio-oil upgrading and pyrolytic lignin hydrocracking. In this work, the effects of the metal-acid bifunctional catalyst prop- erties, including acidity, pore si... The metal-acid bifunctional catalysts have been used for bio-oil upgrading and pyrolytic lignin hydrocracking. In this work, the effects of the metal-acid bifunctional catalyst prop- erties, including acidity, pore size and supported metal on hydrocracking of pyrolytic lignin in supercritical ethanol and hydrogen were investigated at 260 ℃. A series of catalysts were prepared and characterized by BET, XRD, and NHa-TPD techniques. The results showed that enhancing the acidity of the catalyst without metal can promote pyrolytic lignin poly- merization to form more solid and condensation to produce more water. The pore size of microporous catalyst was smaller than mesoporous catalyst. Together with strong acid- ity, it caused pyrolytic lignin further hydrocrack to numerous gas. Introducing Ru into acidic catalysts promoted pyrolytic lignin hydrocracking and inhibited the polymerization and condensation, which caused the yield of pyrolytic lignin liquefaction product to increase significantly. Therefore, bifunctional catalyst with high hydrocracking activity metal Ru supported on materials with acidic sites and mesopores was imperative to get satisfactory results for the conversion of pyrolytic lignin to liquid products under supercritical conditions and hydrogen atmosphere. 展开更多
关键词 Pyrolytic lignin HYDROCRACKING Bifunctional catalyst
下载PDF
Acid‐promoted Ir‐La‐S/AC‐catalyzed methanol carbonylation on single atomic active sites 被引量:4
4
作者 Zhou Ren Yuan Lyu +2 位作者 Siquan Feng Xiangen Song Yunjie Ding 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第6期1060-1069,共10页
Highly active Ir‐La‐S/AC catalyst was successfully prepared by co‐impregnation of an activated carbon(AC) carrier with a sulfuric acid solution of Ir and La species and compared with a tradition‐ally prepared Ir... Highly active Ir‐La‐S/AC catalyst was successfully prepared by co‐impregnation of an activated carbon(AC) carrier with a sulfuric acid solution of Ir and La species and compared with a tradition‐ally prepared Ir‐La/AC catalyst. High angle annular dark‐field‐scanning transmission electron mi‐croscopy(HAADF‐STEM) measurement results show that most of the Ir species on Ir‐La‐S/AC exist as single atomic sites, while those on Ir‐La/AC exist as nanoparticles with an average diameter of 1.5 nm. Evaluation of Ir‐La‐S/AC as a catalyst for heterogeneous carbonylation of methanol to acetyl gave a maximum TOF (turn‐over‐frequency) of 2760 h^–1, which was distinctly higher than that achieved by the Ir‐La/AC catalyst(approximately 1000 h^-1). Temperature‐programmed desorption of ammonia(NH3‐TPD) result shows that the addition of sulfuric acid during the preparation pro‐cedure results in significantly more acidic sites on Ir‐La‐S/AC than those on Ir‐La/AC, which plays a key role in the enhancement of CO insertion as the rate‐determining step. Tempera‐ture‐programmed reduction(TPR) and in situ X‐ray photoelectron spectroscopy reveal that Ir spe‐cies are more reducible, and that more Ir^+ might be formed by activation of Ir‐La‐S/AC than those on the Ir‐La/AC catalyst, which is thought to be beneficial for reductive elimination of AcI from Ir^3+ species as an essential step for CH3I regeneration and acetyl formation. 展开更多
关键词 Heterogeneous METHANOL carbonylationIr‐La‐S/ACcatalyst BIFUNCTIONAL catalyst Single‐atomic active site Co‐impregnation
下载PDF
Amorphous CoOx coupled carbon dots as a spongy porous bifunctional catalyst for efficient photocatalytic water oxidation and CO2 reduction 被引量:4
5
作者 Wanjun Sun Xiangyu Meng +5 位作者 Chunjiang Xu Junyi Yang Xiangming Liang Yinjuan Dong Congzhao Dong Yong Ding 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第12期1826-1836,共11页
Cobalt-based oxides,with high abundance,good stability and excellent catalytic performance,are regarded as promising photocatalysts for artificial photosynthetic systems to alleviate foreseeable energy shortages and g... Cobalt-based oxides,with high abundance,good stability and excellent catalytic performance,are regarded as promising photocatalysts for artificial photosynthetic systems to alleviate foreseeable energy shortages and global warming.Herein,for the first time,a series of novel spongy porous CDs@CoOx materials were synthesized to act as an efficient and stable bifunctional photocatalyst for water oxidation and CO2 reduction.Notably,the preparation temperatures visibly influence the morphologies and photocatalytic performances of the CDs@CoOx.Under the optimal conditions,a maximum O2 yield of 40.4% and pretty apparent quantum efficiency(AQE)of 58.6% at 460 nm were obtained over CDs@CoOx-300 for water oxidation.Similarly,the optimized sample CDs@CoOx-300 manifests significant enhancement on the CO2-to-CO conversion with a high selectivity of 89.3% and CO generation rate of 8.1μmol/h,which is superior to most previous cobalt-based catalysts for CO2 reduction.The composite CDs@CoOx-300 not only exposes more active sites but also facilitates electron transport,which results in excellent photocatalytic activity.In addition,the boosted photocatalytic behavior is attributed to the synergistic effect between CoOx and CDs,which was verified by the photocatalytic activity control experiments and electrochemical characterization.The work offers a novel strategy to fabricate a high performance bifunctional photocatalyst for water oxidation and CO2 reduction. 展开更多
关键词 Carbon dots coupled CoOx Bifunctional photocatalyst Water oxidation CO2 reduction Synergistic effect
下载PDF
Sea urchin‐like NiMoO_(4) nanorod arrays as highly efficient bifunctional catalysts for electrocatalytic/photovoltage‐driven urea electrolysis 被引量:2
6
作者 Chenxin Chen Suqi He +3 位作者 Kamran Dastafkan Zehua Zou Qingxiang Wang Chuan Zhao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第5期1267-1276,共10页
Developing multifunctional electrocatalysts with high catalytic activity,longterm stability,and low cost is essential for electrocatalytic energy conversion.Herein,sea urchinlike NiMoO_(4) nanorod arrays grown on nick... Developing multifunctional electrocatalysts with high catalytic activity,longterm stability,and low cost is essential for electrocatalytic energy conversion.Herein,sea urchinlike NiMoO_(4) nanorod arrays grown on nickel foam has been developed as a bifunctional electrocatalyst for urea oxidation and hydrogen evolution.The NiMoO_(4)‐200/NF catalyst exhibits efficient activity toward hydrogen evolution reaction with a low overpotential of only 68 mV in 1.0 mol/L KOH to gain a current density of 10 mA cm^(–2).The NiMoO_(4)‐300/NF catalyst exhibits a prominent oxygen evolution reaction(OER)catalytic activity with an overpotential of 288 mV at 50 mA cm^(–2),as well as for urea oxidation reaction with an ultralow potential of 1.36 V at 10 mA cm^(–2).The observed difference in electrocatalytic activity and selectivity,derived by temperature variation,is ascribed to different lattice oxygen contents.The lattice oxygen of NiMoO_(4)‐300/NF is more than that of NiMoO_(4)‐200/NF,and the lattice oxygen is conducive to the progress of OER.A urea electrolyzer was assembled with Ni‐MoO_(4)‐200/NF and NiMoO_(4)‐300/NF as cathode and anode respectively,delivering a current density of 10 mA cm^(–2)at a cell voltage of merely 1.38 V.The NiMoO_(4)nanorod arrays has also been successfully applied for photovoltage‐driven urea electrolysis and hydrogen production,revealing its great potential for solar‐driven energy conversion. 展开更多
关键词 NiMoO4 nanorod Bifunctional electrocatalyst Urea electrolysis Photovoltage‐driven Lattice oxygen Sea urchin‐like
下载PDF
M/C_(3)N_(4)/AC(M=Au,Pt,Ru)‐catalyzed acetylene coupling with ethylene dichloride:How effective are the bifunctionalities? 被引量:1
7
作者 Qing Yu Shiyi Wang +3 位作者 Mengru Wang Xiaoling Mou Ronghe Lin Yunjie Ding 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第3期820-831,共12页
Acetylene coupling with ethylene dichloride,which uses both coal and oil resources,is attractive for sustainable PVC manufacturing.Herein,highly active and stable carbon nitride‐based catalysts were developed by a no... Acetylene coupling with ethylene dichloride,which uses both coal and oil resources,is attractive for sustainable PVC manufacturing.Herein,highly active and stable carbon nitride‐based catalysts were developed by a novel pre‐oxidation‐pyrolysis process,affording unprecedented dehydrochlorination activity with good durability.The best‐performing system was further modified with different precious metals(Au,Pt,and Ru)to promote the hydrochlorination chemistry between the in‐situ formed hydrogen chloride and acetylene co‐feed.The presence of metal centers intensifies the hydrochlorination activity but weakens the dehydrochlorination ability due to competitive adsorption between the two reactants at the metal sites.Superior coupling performance was achieved over C_(3)N_(4)/AC and single‐atom Au/C_(3)N_(4)/AC catalysts in cascade reactors.Our results strongly suggest that dehydrochlorination is an essential step in the coupling reaction,and the activation of acetylene and ethylene dichloride molecules requires different active sites that should be engineered in future work. 展开更多
关键词 Acetylene hydrochlorination Bi‐functional catalyst DEHYDROCHLORINATION Ethylene dichloride Vinyl chloride
下载PDF
N‐doped porous carbon nanofibers inlaid with hollow Co_(3)O_(4) nanoparticles as an efficient bifunctional catalyst for rechargeable Li‐O_(2) batteries 被引量:1
8
作者 Hongbin Chen Yaqian Ye +4 位作者 Xinzhi Chen Lili Zhang Guoxue Liu Suqing Wang Liang‐Xin Ding 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第6期1511-1519,共9页
Stable and high‐efficiency bifunctional catalysts for the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)are desired for the practical application of Li‐O_(2)batteries with excellent rate performanc... Stable and high‐efficiency bifunctional catalysts for the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)are desired for the practical application of Li‐O_(2)batteries with excellent rate performance and cycle stability.Herein,a novel hybrid bifunctional catalyst with carbon nanofibers inlaid with hollow Co_(3)O_(4)nanoparticles and separate active sites for ORR and OER were prepared and applied in Li‐O_(2)batteries.Benefiting from the synergistic effect of unique porous structural features and high electrocatalytic activity of hollow Co3O4 intimately bound to N‐doped carbon nanofibers,the assembled Li‐O_(2)batteries with novel catalyst exhibited high specific capacity,excellent rate capability,and cycle stability up to 150 cycles under a capacity limitation of 500 mAh g^(–1)at a current density of 100 mA g^(–1).The facile synthesis and preliminary results in this work show the as‐prepared catalyst as a promising bifunctional electrocatalyst for applications in metal‐air batteries,fuel cells,and electrocatalysis. 展开更多
关键词 Li‐O_(2)batteries Bifunctional catalyst Co_(3)O_(4) N‐doped carbon nanofibers Oxygen reduction reaction Oxygen evolution reaction
下载PDF
Geometric and electronic effects on the performance of a bifunctional Ru2P catalyst in the hydrogenation and acceptorless dehydrogenation of N‐heteroarenes 被引量:1
9
作者 Fangjun Shao Zihao Yao +7 位作者 Yijing Gao Qiang Zhou Zhikang Bao Guilin Zhuang Xing Zhong Chuan Wu Zhongzhe Wei Jianguo Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第7期1185-1194,共10页
The development of bifunctional catalysts for the efficient hydrogenation and acceptorless dehydrogenation of N‐heterocycles is a challenge.In this study,Ru_(2)P/AC effectively promoted reversible transformations bet... The development of bifunctional catalysts for the efficient hydrogenation and acceptorless dehydrogenation of N‐heterocycles is a challenge.In this study,Ru_(2)P/AC effectively promoted reversible transformations between unsaturated and saturated N‐heterocycles affording yields of 98%and 99%,respectively.Moreover,a remarkable enhancement in the reusability of Ru_(2)P/AC was observed compared with other Ru‐based catalysts.According to density functional theory calculations,the superior performance of Ru_(2)P/AC was ascribed to specific synergistic factors,namely geometric and electronic effects induced by P.P greatly reduced the large Ru‐Ru ensembles and finely modified the electronic structures,leading to a low reaction barrier and high desorption ability of the catalyst,further boosting the hydrogenation and acceptorless dehydrogenation processes. 展开更多
关键词 Ruthenium phosphide Bifunction catalyst Reaction mechanism Geometric and electronic effects HYDROGENATION Acceptorless dehydrogenation
下载PDF
Toluene methylation with syngas to para‐xylene by bifunctional ZnZrO_(x)‐HZSM‐5 catalysts 被引量:2
10
作者 Xiaoqin Han Jiachang Zuo +1 位作者 Danlu Wen Youzhu Yuan 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第4期1156-1164,共9页
Toluene methylation with methanol on H‐ZSM‐5(Z5)zeolite for the directional transformation of toluene to xylene has been industrialized.However,great challenges remain because of the high energy barrier of methanol ... Toluene methylation with methanol on H‐ZSM‐5(Z5)zeolite for the directional transformation of toluene to xylene has been industrialized.However,great challenges remain because of the high energy barrier of methanol deprotonation to the methoxy group,the side reaction of methanol to olefins,coke formation,and the deactivation of zeolites.Herein,we report the toluene methylation coupled with CO hydrogenation to showcase an enhancement in para‐xylene(PX)selectivity by employing a bifunctional catalyst composed of ZnZrO_(x)(ZZO)and modified Z5.The results showed that a PX selectivity of up to 81.8%in xylene and xylene selectivity of 64.8%in hydrocarbons at 10.3%toluene conversion can be realized over the bifunctional catalyst on a fixed‐bed reactor.The selectivity of gaseous hydrocarbons decreased to 10.9%,and approximately half of that was observed in methanol reagent route where the PX selectivity in xylene was 38.8%.We observed that the acid strength,the quantity ratio of Brönsted and Lewis acid sites,and the pore size of zeolites were essential for the PX selectivity.The investigation of the H_(2)/D_(2) kinetic isotope effect revealed that the newborn methyl group in xylene resulted from the hydrogenation of CO rather than toluene disproportionation.Furthermore,the catalyst showed no evident deactivation within the 100 h stability test.The findings offer a promising route for the production of value‐added PX with high selectivity via toluene methylation coupled with syngas conversion. 展开更多
关键词 Toluene methylation Syngas conversion Para‐xylene Bifunctional catalyst ZnZrO_(x)‐ZSM‐5
下载PDF
Precisely decorating CdS on Zr-MOFs through pore functionalization strategy: A highly efficient photocatalyst for H2 production 被引量:1
11
作者 Haijun Hu Kailai Zhang +6 位作者 Ge Yan Litong Shi Baohua Jia Hongwei Huang Yu Zhang Xiaodong Sun Tianyi Ma 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第9期2332-2341,共10页
Different materials,such as metal sulphides,are often combined with metal‐organic frameworks(MOFs)to develop multi‐functional composites and improve their photocatalytic properties.However,the high interfacial energ... Different materials,such as metal sulphides,are often combined with metal‐organic frameworks(MOFs)to develop multi‐functional composites and improve their photocatalytic properties.However,the high interfacial energy barrier limits the formation and nano‐assembly of the heterogeneous junctions between MOFs and metal sulphides.Herein,the heterostructured Zr‐MOF‐S@CdS are successfully constructed through a sequential synthesis method,in which the mesoporous Zr‐MOF are firstly decorated with thioglycolic acid through pore functionalization,and followed by the S^(2-)anion exchange process resulting in the surface close attached growth of CdS onto Zr‐MOF‐S materials.Due to the presence of molecules linkers,the CdS can be precisely decorated onto Zr‐MOF‐S without aggregation,which can provide more active sites.Moreover,the intimate connections and the suitable band structures between two materials can also facilitate the photogenerated electron‐hole pairs separation.Therefore,the resulting Zr‐MOF‐S@CdS with appropriate ratio exhibits high photocatalytic activity for water reduction,in which the H_(2) evolution rate can reach up to 1861.7μmol·g^(‒1)·h^(‒1),4.5 times higher than pure CdS and 2.3 times higher than of Zr‐MOF/CdS,respectively.Considering the promising future of MOF‐based photocatalysts,this work may provide an avenue for the further design and synthesis MOF‐based composite photocatalysts for efficient H_(2) evolution. 展开更多
关键词 Zr-MOF Pore functionalization Photocatalytic H2 production Molecular linker Junction
下载PDF
Synthesis of 4,4'-MDC in the Presence of Sulfonic Acid-functionalized Ionic Liquids 被引量:12
12
作者 耿艳楼 胡利彦 +2 位作者 赵新强 安华良 王延吉 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第5期756-760,共5页
The synthesis of methylene diphenyl dimethylcarbamate (4,4'-MDC) from methyl N-phenyl carbonate (MPC) and formaldehyde (HCHO) was conducted in the presence of sulfonic acid-functionalized ionic liquids (ILs) ... The synthesis of methylene diphenyl dimethylcarbamate (4,4'-MDC) from methyl N-phenyl carbonate (MPC) and formaldehyde (HCHO) was conducted in the presence of sulfonic acid-functionalized ionic liquids (ILs) as dual solvent-catalyst. The influences of the kind of anion in the ionic liquids, reaction conditions and the recycle of the ionic liquid on 4,4'-MDC synthesis reaction were investigated. In addition, the acid strength of ILs was de-termined by the Hammett method with UV-visible spectroscopy, and the acid strength-catalytic activity relationship was correlated. The activity estimation results showed that [HSO3-bmim]CF3SO3 was the optimal dual solvent-catalyst. Under the suitable reaction conditions of 70℃, 40 min, molar ratio of nMPC/nHCHO= 10/1 and mass ratio of WILs/WMPC = 4.5/1, the yield of 4,4'-MDC based on HCHO was 89.9 % and the selectivity of 4,4'-MDC with respect to MPC was 74.9%. Besides, [HSO3-bmim]CF3SO3 was reused four times after being purified and no significant loss in the catalytic activity was observed. 展开更多
关键词 ionic liquids methyl N-phenyl carbonate FORMALDEHYDE methylene diphenyl dimethylcarbamate Bronsted acidity catalyst recycling
下载PDF
Reaction kinetics for synthesis of sec-butyl alcohol catalyzed by acid-functionalized ionic liquid 被引量:7
13
作者 邱挺 唐文莉 +2 位作者 李承港 吴承明 李玲 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期106-111,共6页
The acid-functionalized ionic liquid([HSO3Pmim]HSO4) was synthesized by a two-step method. Nuclear magnetic resonance(NMR) and Fourier transform infrared spectroscopy(FT-IR) show that the synthesis method is feasible ... The acid-functionalized ionic liquid([HSO3Pmim]HSO4) was synthesized by a two-step method. Nuclear magnetic resonance(NMR) and Fourier transform infrared spectroscopy(FT-IR) show that the synthesis method is feasible and high purity of ionic liquid can be obtained. Using [HSO3Pmim]HSO4as the catalyst, we studied the reaction kinetics of synthesizing sec-butyl alcohol from sec-butyl acetate and methanol by transesterification in a high-pressure batch reactor. The effects of temperature, initial molar ratio of methanol to ester, and catalyst concentration on the conversion of sec-butyl acetate were studied. Based on its possible reaction mechanism, a homogeneous kinetic model was established. The results show that the reaction heat ΔH is 10.94 × 103J·mol-1, so the reaction is an endothermic reaction. The activation energies Ea+and Ea-are 60.38 × 103 and 49.44 × 103J·mol-1,respectively. 展开更多
关键词 Ionic liquids sec-Butyl alcohol Kinetic modeling TRANSESTERIFICATION
下载PDF
Fabrication of Pd-based metal-acid-alkali multifunctional catalysts for one-pot synthesis of MIBK 被引量:5
14
作者 Rui Ma Yunpeng Li +4 位作者 Guandong Wu Yufei He Junting Feng Yingying Zhao Dianqing Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第8期1384-1394,共11页
The one-pot synthesis of methyl isobutyl ketone(MIBK) from acetone using multifunctional catalysts is an important sustainable organic synthesis method with high atom and energy efficiency.Herein. we report a series... The one-pot synthesis of methyl isobutyl ketone(MIBK) from acetone using multifunctional catalysts is an important sustainable organic synthesis method with high atom and energy efficiency.Herein. we report a series of Pd supported on mixed metal oxide(MMO) catalysts with controllable acidic/basic/metallic sites on the surface. We study the relationship between the nature, synergy,and proximity of active sites and the catalytic performance of the multifunctional catalyst in the tandem reaction, in detail. In the existence of Lewis acid and base sites, the catalysts with medium-strength acidic/basic sites show preferred activity and/or MIBK selectivity. For multifunctional catalysts, the catalytic properties are more than just a collection of active sites, and the Pd/Mg_3Al-MMO catalyst possessing 0.1% Pd loading and ~0.4 acid/base molar ratio exhibits the optimal 42.1% acetone conversion and 37.2% MIBK yield, which is among the best reported so far for this tandem reaction under similar conditions. Moreover, the proximity test indicates that the intimate distance between acidic/basic/metallic sites can greatly shorten the diffusion time of the intermediate species from each active site, leading to an enhancement in the catalytic performance. 展开更多
关键词 One‐pot synthesisof methyl isobutyl ketone Multifunctional catalyst PdMg3Al mixedmetal oxide Synergy effect PROXIMITY
下载PDF
Commercial Test of Multi-functional Desulfurizing Agent TS-01 for Gasoline in FCC Process
15
作者 Cai Zhi Wu Yingjian Yu Weisheng( SINOPEC Jiujiang Company, Jiujiang, Jiangxi 332004) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2003年第1期43-46,共4页
Experimental use of multi-functional desulfurizing agent TS-01 for FCC gasoline in the FCC unitof SINOPEC Jiujiang Company shows that the multi-functional desulfurizing agent can effectivelyremove various kinds of sul... Experimental use of multi-functional desulfurizing agent TS-01 for FCC gasoline in the FCC unitof SINOPEC Jiujiang Company shows that the multi-functional desulfurizing agent can effectivelyremove various kinds of sulfur in FCC gasoline and diesel fuel and fulfill passivation on heavy metals. 展开更多
关键词 FCC GASOLINE DESULFURIZATION commercial test
下载PDF
Metal-free porous nitrogen-doped carbon nanotubes for enhanced oxygen reduction and evolution reactions 被引量:10
16
作者 Ting Pan Hongying Liu +3 位作者 Guangyuan Ren Yunan Li Xianyong Lu Ying Zhu 《Science Bulletin》 SCIE EI CAS CSCD 2016年第11期889-896,共8页
Developing efficient metal-free bi-functional electrocatalysts is required to reduce costs and improve the slow oxygen reduction reaction (ORR) and oxygen evo- lution reaction (OER) kinetics in electrochemical sys... Developing efficient metal-free bi-functional electrocatalysts is required to reduce costs and improve the slow oxygen reduction reaction (ORR) and oxygen evo- lution reaction (OER) kinetics in electrochemical systems. Porous N-doped carbon nanotubes (NCNTs) were fabri- cated by KOH activation and pyrolysis of polypyrrole nanotubes. The NCNTs possessed a large surface area of more than 1,000 m2 g-1. NCNT electrocatalysts, particu- larly those annealed at 900 ℃, exhibited excellent ORR electrocatalytic performance. Specifically, they yielded a more positive onset potential, higher current density, and long-term operation stability in alkaline media, when compared with a commercially available 20 wt% Pt/C catalyst. This resulted from the synergetic effect between the dominant pyridinic/graphitic-N species and the porous tube structures. The NCNT electrocatalyst also exhibited good performance for the OER. The metal-free porous nitrogen-doped carbon nanomaterials were prepared from low cost and environmentally friendly precursors. They are potential alternatives to Pt/C catalysts, for electrochemical energy conversion and storage. 展开更多
关键词 N-doped porous carbon POLYPYRROLE ELECTROCATALYST Oxygen reduction reaction Oxygenevolution reaction
原文传递
Metal@Silica Yolk-Shell Nanostructures as Versatile Bifunctional Nanocatalysts 被引量:6
17
作者 Ji Chan Park Hyunjoon Song 《Nano Research》 SCIE EI CAS CSCD 2011年第1期33-49,共17页
Recent developments in nanochemistry offer precise morphology control of nanomaterials, which has significant impacts in the field of heterogeneous catalysis. Rational design of bifunctional catalysts can influence va... Recent developments in nanochemistry offer precise morphology control of nanomaterials, which has significant impacts in the field of heterogeneous catalysis. Rational design of bifunctional catalysts can influence various aspects of catalytic properties. In this review, a new class of bifunctional catalysts with a metal@silica yolk-shell nanostructure is introduced. This structure has many advantages as a heterogeneous catalyst since it ensures a homogeneous environment around each metal core, and particle sintering is effectively eliminated during high temperature reactions. The catalysts exhibit high activity and recyclability in gas- and solution-phase reactions. It is anticipated that appropriate selection of bifunctional components and optimal structural control will significantly further enhance the catalytic properties, and enable target reaction-oriented development of new catalysts. 展开更多
关键词 Yolk-shell nanostructure NANOCATALYST bifunctionality metal nanoparticles heterogeneous catalytic reactions
原文传递
Synergistic trifunctional electrocatalysis of pyridinic nitrogen and single transition-metal atoms anchored on pyrazine-modified graphdiyne 被引量:3
18
作者 Siyun Qi Junru Wang +4 位作者 Xiaohan Song Yingcai Fan Weifeng Li Aijun Du Mingwen Zhao 《Science Bulletin》 SCIE EI CAS CSCD 2020年第12期995-1002,M0003,共9页
Multifunctional catalysts that integrate high efficiency hydrogen evolution reaction(HER), oxygen evolution reaction(OER) and oxygen reduction reaction(ORR) catalytic activity in a single material are attractive for u... Multifunctional catalysts that integrate high efficiency hydrogen evolution reaction(HER), oxygen evolution reaction(OER) and oxygen reduction reaction(ORR) catalytic activity in a single material are attractive for unitized regenerative fuel cells and overall water splitting technologies. As the best-known HER and ORR electrocatalysts, Pt and its alloys have only moderate OER activity. Ruthenium and iridium oxides exhibit the highest OER activities but not as active as Pt for HER and ORR. Here, we proposed a general principle for achieving trifunctional electrocatalysis for three reactions in a single material. Using the newly-synthesized pyrazine-modified graphdiyne(PR-GDY) as an example, we demonstrated that the synergistic effect of the pyridinic nitrogen and anchored transition-metal(TM) single atoms renders highly-efficient HER/OER/ORR trifunctional electrocatalytic activity. For the Ni-doped PR-GDY, the overpotentials for HER, OER and ORR can be respectively as low as -0.05, 0.29 and 0.38 V, which are comparable or even superior to the best-known single-functional and bi-functional precious electrocatalysts.These computational results offer not only a promising trifunctional electrocatalyst but also a strategy for the design of multifunctional electrocatalysts. 展开更多
关键词 Trifunctional electrocatalysts Pyrazine-modified graphdiyne(PR-GDY) Single atoms Density-functional theory
原文传递
Recyclable bifunctional aluminum salen catalyst for CO2 fixation:the efficient formation of five-membered heterocyclic compounds 被引量:4
19
作者 Rongchang Luo Zhi Yang +2 位作者 Wuying Zhang Xiantai Zhou Hongbing Ji 《Science China Chemistry》 SCIE EI CAS CSCD 2017年第7期979-989,共11页
A variety of unique Al(salen) complexes functionalized by imidazolium-based ionic liquid(IL) moieties with the salen ligand at the two sides of 3,3′-position have been successfully prepared, rather than familiar 5,5... A variety of unique Al(salen) complexes functionalized by imidazolium-based ionic liquid(IL) moieties with the salen ligand at the two sides of 3,3′-position have been successfully prepared, rather than familiar 5,5′-position reported previously.The catalytic activity obtained by these bifunctional catalysts could be superior to those of the binary type catalysts in the formation of five-membered heterocyclic compounds from the cycloaddition reaction of CO_2 and three-membered heterocyclic compounds(including terminal epoxides and N-substituted aziridines), presumably due to the distinguished intramolecularly synergistic catalysis, which might lead to perform the cycloaddition reaction at ambient conditions and retain excellent yield and unprecedented chemo-or regioselectivity. Moreover, the polyether-based trifunctional Al(salen) catalysts with the best catalytic performance could be regenerated and reused at least eight times without any obvious decreases in catalytic activity. Finally,the kinetic investigation suggested the structure of catalysts had important influences on the catalytic activity, thereby proposing the possible reaction mechanism. 展开更多
关键词 carbon dioxide cyclic carbonate salen aluminum bifunctional catalyst cooperative effect
原文传递
Ru-Co-Mn trimetallic alloy nanocatalyst driving bifunctional redox electrocatalysis 被引量:1
20
作者 Shan Liu Erhuan Zhang +6 位作者 Xiaodong Wan Rongrong Pan Yuemei Li Xiuming Zhang Mengyao Su Jia Liu Jiatao Zhang 《Science China Materials》 SCIE EI CAS CSCD 2022年第1期131-138,共8页
Water electrolysis is one of the most promising approaches for producing hydrogen.However,it has been hindered by the sluggishness of the anodic oxygen evolution reaction.In this work,we fabricated Ru-Co-Mn trimetalli... Water electrolysis is one of the most promising approaches for producing hydrogen.However,it has been hindered by the sluggishness of the anodic oxygen evolution reaction.In this work,we fabricated Ru-Co-Mn trimetallic alloy nanoparticles on N-doped carbon support(RuCoMn@NC)via the pyrolysis-adsorption-pyrolysis process using ZIF-67 as a precursor.The RuCoMn@NC catalyst exhibited excellent electrocatalytic performance for the hydrogen evolution reaction(HER)over a wide range of pH and glucose oxidation reaction in alkaline media.It showed exceptional HER activity in alkaline medium,superior to that of the commercial Pt/C catalyst(20 wt%),and good electrochemical stability.Further,a two-electrode alkaline electrolyzer pairing RuCoMn@NC as both cathode and anode was employed,and only a cell voltage of 1.63 V was required to attain a current density of 10 mA cm^(-2)in glucose electrolysis,which is about 270 mV lower than that in the overall water-splitting electrolyzer.This paper provides a promising method for developing efficiently bifunctional electrocatalysts driving redox electrocatalysis,and it would be beneficial to energy-saving electrolytic H_(2) production. 展开更多
关键词 Ru-Co-Mn trimetallic alloy HER glucose oxidation reaction redox electrocatalysis
原文传递
上一页 1 2 下一页 到第
使用帮助 返回顶部