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Deformable Catalytic Material Derived from Mechanical Flexibility for Hydrogen Evolution Reaction 被引量:2
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作者 Fengshun Wang Lingbin Xie +7 位作者 Ning Sun Ting Zhi Mengyang Zhang Yang Liu Zhongzhong Luo Lanhua Yi Qiang Zhao Longlu Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期287-311,共25页
Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent year... Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent years,deformable catalysts for HER have made great progress and would become a research hotspot.The catalytic activities of deformable catalysts could be adjustable by the strain engineering and surface reconfiguration.The surface curvature of flexible catalytic materials is closely related to the electrocatalytic HER properties.Here,firstly,we systematically summarized self-adaptive catalytic performance of deformable catalysts and various micro–nanostructures evolution in catalytic HER process.Secondly,a series of strategies to design highly active catalysts based on the mechanical flexibility of lowdimensional nanomaterials were summarized.Last but not least,we presented the challenges and prospects of the study of flexible and deformable micro–nanostructures of electrocatalysts,which would further deepen the understanding of catalytic mechanisms of deformable HER catalyst. 展开更多
关键词 Deformable catalytic material Micro-nanostructures evolution Mechanical flexibility Hydrogen evolution reaction
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Recent advances in cobalt phosphide-based materials for electrocatalytic water splitting:From catalytic mechanism and synthesis method to optimization design 被引量:1
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作者 Rongrong Deng Mengwei Guo +1 位作者 Chaowu Wang Qibo Zhang 《Nano Materials Science》 EI CAS CSCD 2024年第2期139-173,共35页
Electrochemical water splitting has long been considered an effective energy conversion technology for trans-ferring intermittent renewable electricity into hydrogen fuel,and the exploration of cost-effective and high... Electrochemical water splitting has long been considered an effective energy conversion technology for trans-ferring intermittent renewable electricity into hydrogen fuel,and the exploration of cost-effective and high-performance electrocatalysts is crucial in making electrolyzed water technology commercially viable.Cobalt phosphide(Co-P)has emerged as a catalyst of high potential owing to its high catalytic activity and durability in water splitting.This paper systematically reviews the latest advances in the development of Co-P-based materials for use in water splitting.The essential effects of P in enhancing the catalytic performance of the hydrogen evolution reaction and oxygen evolution reaction are first outlined.Then,versatile synthesis techniques for Co-P electrocatalysts are summarized,followed by advanced strategies to enhance the electrocatalytic performance of Co-P materials,including heteroatom doping,composite construction,integration with well-conductive sub-strates,and structure control from the viewpoint of experiment.Along with these optimization strategies,the understanding of the inherent mechanism of enhanced catalytic performance is also discussed.Finally,some existing challenges in the development of highly active and stable Co-P-based materials are clarified,and pro-spective directions for prompting the wide commercialization of water electrolysis technology are proposed. 展开更多
关键词 Co-P electrocatalysts Water splitting Hydrogen production catalytic mechanism Synthesis technique Optimization design
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Effects of drought on non-structural carbohydrates and C,N,and P stoichiometric characteristics of Pinus yunnanensis seedlings
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作者 Zhijuan Zhao Lina Wang +7 位作者 Yuanxi Liu Jianli Sun Jiandong Xiao Qiong Dong Lianfang Li Wanjie Zhang Chao Wang Junwen Wu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期90-102,共13页
To study non-structural carbohydrate character-istics and nutrient utilization strategies of Pinus yunnanen-sis under continuous drought conditions,2-year-old seed-lings were planted in pots with appropriate water,lig... To study non-structural carbohydrate character-istics and nutrient utilization strategies of Pinus yunnanen-sis under continuous drought conditions,2-year-old seed-lings were planted in pots with appropriate water,light and moderate and severe drought treatments[(80±5),(65±5),(50±5),and(35±5)%of field water-holding capacity].Non-structural carbohydrates,carbon(C),nitrogen(N),and phosphorus(P)concentrations were measured in each plant component.The results show that:(1)With increasing drought,non-structural carbohydrates gradually increased in leaves,stems,and coarse roots,while gradually decreased in fine roots;(2)C concentrations of all were relatively stable under different stress levels.Phosphorous utilization of each component increased under light and moderate drought conditions,while N and P utilization efficiency of each plant component decreased under severe drought.Growth was mainly restricted by N,first decreasing and then increasing with increased drought;(3)There was a correlation between the levels of non-structural carbohydrates and C,N,and P in each component.Changes in N concentration affected the interconversion between soluble sugar and starch,which play a regulatory role in the fluctuation of the concentration of non-structural carbohydrates;and,(4)Plasticity analysis showed that P.yunnanensis seedlings responded to drought mainly by altering starch concentration,the ratio of soluble sugar to starch in leaves and stems,and further by alter-ing N and P utilization efficiencies.Overall,these results suggest that the physiological activities of all organs of P.yunnanensis seedlings are restricted under drought and that trade-offs exist between different physiological indicators and organs.Our findings are helpful in understanding non-structural carbohydrate and nutrient adaptation mechanisms under drought in P.yunnanensis seedlings. 展开更多
关键词 Pinus yunnanensis seedlings DROUGHT Non-structural carbohydrates C N P stoichiometric characteristics
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Critical approaches in the catalytic transformation of sugar isomerization and epimerization after Fischer-History,challenges,and prospects
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作者 Da-Ming Gao Xun Zhang +5 位作者 Haichao Liu Hidemi Fujino Tingzhou Lei Fuan Sun Jie Zhu Taoli Huhe 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第3期435-453,共19页
The transformation of aldose to ketose or common sugars into rare saccharides,including rare ketoses and aldoses,is of great value and interest to the food industry and for saccharidic biomass utilization,medicine,and... The transformation of aldose to ketose or common sugars into rare saccharides,including rare ketoses and aldoses,is of great value and interest to the food industry and for saccharidic biomass utilization,medicine,and the synthesis of drugs.Nowadays,high-fructose corn syrup(HFCS)is industrially produced in more than 10 million tons annually using immobilized glucose isomerase.Some low-calorie saccharides such as tagatose and psicose,which are becoming popular sweeteners,have also been produced on a pilot scale in order to replace sucrose and HFCS.However,current catalysts and catalytic processes are still difficult to utilize in biomass conversion and also have strong substrate dependence in producing high-value,rare sugars.Considering the specific reaction properties of saccharides and catalysts,since the pioneering discovery by Fischer,various catalysts and catalytic systems have been discovered or developed in attempts to extend the reaction pathways,improve the reaction efficiency,and to potentially produce commercial products.In this review,we trace the history of sugar isomerization/epimerization reactions and summarize the important breakthroughs for each reaction as well as the difficulties that remain unresolved to date. 展开更多
关键词 Rare sugars ISOMERIZATION KETONIZATION EPIMERIZATION catalytic transformation
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Development and Catalytic Cracking Performance of Ultrastable Y Zeolite Rich in Secondary Pores
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作者 Li Jiaxing Wang Shengji +3 位作者 Sha Hao Wang Juan Zhou Lingping Wang Lixia 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第2期13-21,共9页
A novel ultra-stable zeolite, NSZ, rich in secondary pores was developed through the combination of gas-phase andmild hydrothermal methods. This zeolite was successfully tested in an industrial setting for the first t... A novel ultra-stable zeolite, NSZ, rich in secondary pores was developed through the combination of gas-phase andmild hydrothermal methods. This zeolite was successfully tested in an industrial setting for the first time in the world. The porestructure characteristics of the NSZ zeolite prepared for industrial use were analyzed and characterized using BET. The resultsindicate a significant increase in the secondary pore volume of NSZ zeolite compared to the existing ultra-stable zeolite HSZ-5, which is produced through a conventional gas-phase method. The average secondary pore volume to total pore volume ratioin NSZ zeolite was found to be 58.96% higher. The catalytic cracking performance of NSZ zeolite was evaluated. The resultsshowed that the NSC-LTA catalyst, with NSZ as the active component, outperformed the HSC-LTA catalyst with HSZ-5 zeolitein terms of obtaining more high-value products (gasoline and liquefied petroleum gas) during the hydrogenated light cycle oilprocessing. Additionally, the NSC-LTA catalyst showed a significant improvement in coke selectivity. 展开更多
关键词 GAS-PHASE ultra-stable ZEOLITE CATALYST catalytic cracking
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Green synthesis of ZSM-5 using silica fume and catalytic co-cracking of lignin and plastics for production of monocyclic aromatics
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作者 Hongbing Fu Yufei Gu +7 位作者 Tianhua Gao Fuwei Li Hengshuo Gu Hucheng Ge Yuke Liu Zhixia Li Hongfei Lin Jiangfei Cao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期92-105,共14页
ZSM-5 with hierarchical pore structure was synthesized by a simple two-step hydrothermal crystallization from silica fume without using any organic ammonium templates.The synthesized ZSM-5 were oval shaped particles w... ZSM-5 with hierarchical pore structure was synthesized by a simple two-step hydrothermal crystallization from silica fume without using any organic ammonium templates.The synthesized ZSM-5 were oval shaped particles with a particle size about 2.0 μm and weak acid-dominated with proper Brønsted(B)and Lewis(L)acid sites.The ZSM-5 was used for catalytic co-cracking of n-octane and guaiacol,lowdensity polyethylene(LDPE)and alkali lignin(AL)to enhance the production of benzene,toluene,ethylbenzene and xylene(BTEX).The most significant synergistic effect occurred at n-octane/guaiacol at 1:1 and LDPE/AL at 1:3,under the condition,the achieved BTEX selectivity were 24%and 33%(mass)higher than the calculated values(weighted average).The highest BTEX selectivity reached 88.5%,which was 3.7%and 54.2%higher than those from individual cracking LDPE and AL.The synthesized ZSM-5 exhibited superior catalytic performance compared to the commercial ZSM-5,indicating potential application prospect. 展开更多
关键词 Silica fume ZSM-5 catalytic co-cracking PLASTICS LIGNIN
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HZSM-5 zeolites undergoing the high-temperature process for boosting the bimolecular reaction in n-heptane catalytic cracking
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作者 Chenggong Song Zhenzhou Ma +6 位作者 Xu Hou Hao Zhou Huimin Qiao Changchang Tian Li Yin Baitang Jin Enxian Yuan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期136-144,共9页
High-temperature treatment is key to the preparation of zeolite catalysts.Herein,the effects of hightemperature treatment on the property and performance of HZSM-5 zeolites were studied in this work.X-Ray diffraction,... High-temperature treatment is key to the preparation of zeolite catalysts.Herein,the effects of hightemperature treatment on the property and performance of HZSM-5 zeolites were studied in this work.X-Ray diffraction,N2physisorption,27Al magic angle spinning nuclear magnetic resonance(MAS NMR),and temperature-programmed desorption of ammonia results indicated that the hightemperature treatment at 650℃ hardly affected the inherent crystal and texture of HZSM-5zeolites but facilitated the conversion of framework Al to extra-framework Al,reducing the acid site and enhancing the acid strength.Moreover,the high-temperature treatment improved the performance of HZSM-5 zeolites in n-heptane catalytic cracking,promoting the conversion and light olefins yield while inhibiting coke formation.Based on the kinetic and mechanism analysis,the improvement of HZSM-5 performance caused by high-temperature treatment has been attributed to the formation of extra-framework Al,which enhanced the acid strength,facilitated the bimolecular reaction,and promoted the entropy change to overcome a higher energy barrier in n-heptane catalytic cracking. 展开更多
关键词 HZSM-5 N-HEPTANE catalytic cracking High-temperature treatment Extra-framework Al
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A critical review on direct catalytic hydrogasification of coal into CH_(4):catalysis process configurations,evaluations,and prospects
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作者 Shuai Yan Jun Feng +4 位作者 Shenfu Yuan Zihong Xia Fengshuang Han Xuan Qu Jicheng Bi 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第3期51-85,共35页
Coal catalytic hydrogasification(CCHG)is a straightforward approach for producing CH_(4),which shows advantages over the mature coal-to-CH_(4) technologies from the perspectives of CH_(4) yield,thermal efficiency,and ... Coal catalytic hydrogasification(CCHG)is a straightforward approach for producing CH_(4),which shows advantages over the mature coal-to-CH_(4) technologies from the perspectives of CH_(4) yield,thermal efficiency,and CO_(2) emission.The core of CCHG is to make carbon in coal convert into CH_(4) efficiently with a catalyst.In the past decades,intensive research has been devoted to catalytic hydrogasification of model carbon(pitch coke,activated carbon,coal char).However,the chemical process of CCHG is still not well understood because the coal structure is more complicated,and CCHG is a combination of coal catalytic hydropyrolysis and coal char catalytic hydrogasification.This review seeks to shed light on the catalytic process of raw coal during CCHG.The configuration of suitable catalysts,operating conditions,and feedstocks for tailoring CH_(4) formation were identified,and the underlying mechanisms were elucidated.Based on these results,the CCHG process was evaluated,emphasizing pollutant emissions,energy efficiency,and reactor design.Furthermore,the opportunities and strategic approaches for CCHG under the restraint of carbon neutrality were highlighted by considering the penetration of“green”H2,biomass,and CO_(2) into CCHG.Preliminary investigations from our laboratories demonstrated that the integrated CCHG and biomass/CO_(2) hydrogenation process could perform as an emerging pathway for boosting CH_(4) production by consuming fewer fossil fuels,fulfilling the context of green manufacturing.This work not only provides systematic knowledge of CCHG but also helps to guide the efficient hydrogenation of other carbonaceous resources such as biomass,CO_(2),and coal-derived wastes. 展开更多
关键词 Coal gasification catalytic hydrogasification Methane Pressurized fluidized bed
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A review of the catalytic preparation of mesophase pitch
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作者 MA Zi-hui YANG Tao +7 位作者 SONG Yan CHEN Wen-sheng DUAN Chun-feng SONG Huai-he TIAN Xiao-dong GONG Xiang-jie LIU Zheng-yang LIU Zhan-jun 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第4期583-610,共28页
Because of its high purity and excellent orientation, mesophase pitch is a superior precursor for high-performance car-bon materials. However, the preparation of top-notch mesophase pitch faces challenges. Catalytic p... Because of its high purity and excellent orientation, mesophase pitch is a superior precursor for high-performance car-bon materials. However, the preparation of top-notch mesophase pitch faces challenges. Catalytic polycondensation at low temperat-ures is more favorable for synthesizing mesophase pitch, because it circumvents the high-temperature free radical reaction of other thermal polycondensation approaches. The reaction is gentle and can be easily controlled. It has the potential to significantly im-prove the yield of mesophase pitch and easily introduce naphthenic characteristics into the molecules, catalytic polycondensation is therefore a preferred method of synthesizing highly spinnable mesophase pitch. This review provides a synopsis of the selective pre-treatment of the raw materials to prepare different mesophase pitches, and explains the reaction mechanism and associated research advances for different catalytic systems in recent years. Finally, how to manufacture high-quality mesophase pitch by using a cata-lyst-promoter system is summarized and proposed, which may provide a theoretical basis for the future design of high-quality pitch molecules. 展开更多
关键词 Mesophase pitch catalytic polycondensation LEWIS-ACID Brønsted acid Catalyst-promoter system
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Syntheses and catalytic performances of three coordination polymers with tetracarboxylate ligands
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作者 MEI Zhenzhong WANG Hongyu +2 位作者 KANG Xiuqi SHAO Yongliang GU Jinzhong 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第9期1795-1802,共8页
Three zincand cobaltcoordination polymers,namely{[Zn_(2)(μ_(6)-adip)(phen)_(2)]·4H_(2)O}_(n)(1),{[Co_(2)(μ_(6)-adip)(bipy)_(2)]·4H_(2)O}_(n)(2),and[Co_(2)(μ4-adip)(μ-bpa)_(2)]_(n)(3)have been constructed... Three zincand cobaltcoordination polymers,namely{[Zn_(2)(μ_(6)-adip)(phen)_(2)]·4H_(2)O}_(n)(1),{[Co_(2)(μ_(6)-adip)(bipy)_(2)]·4H_(2)O}_(n)(2),and[Co_(2)(μ4-adip)(μ-bpa)_(2)]_(n)(3)have been constructed hydrothermally using H4adip(H4adip=5,5′-azanediyldiisophthalic acid),phen(phen=1,10-phenanthroline),bipy(bipy=2,2′-bipyridine),bpa(bpa=bis(4-pyridyl)amine),and zinc and cobalt chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and single-crystal X-ray diffrac-tion analyses.Single-crystal X-ray diffraction analyses revealed that three compounds crystallize in the orthorhom-bic system Pnna(1 and 2)or P21212(3)space groups.All compounds exhibit 3D frameworks.The catalytic perfor-mances in the Henry reaction of these compounds were investigated.Compound 3 exhibited an effective catalytic activity in the Henry reaction at 70℃.CCDC:2339391,1;2339392,2;2339393,3. 展开更多
关键词 coordination polymer tetracarboxylic acid catalytic properties Henry reaction
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Promoted catalytic property of Cu/SSZ-13 by introducing a minority of Mn for NO removal from diesel engine exhaust
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作者 Runnong Yang Wuyuan Liu +6 位作者 Zhaoying Wang Ming Sun Guangying Fu Zihan Gao Wenjian Jiao Rui Li Lin Yu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第7期172-182,共11页
The Cu-exchanged SSZ-13 with the small-pore chabazite framework is considered as a highly efficient catalyst for selective catalytic reduction of NO with NH_(3)(NH_(3)-SCR).In order to further improve the catalytic pr... The Cu-exchanged SSZ-13 with the small-pore chabazite framework is considered as a highly efficient catalyst for selective catalytic reduction of NO with NH_(3)(NH_(3)-SCR).In order to further improve the catalytic property,a series of Mn ion-assisted Cu/SSZ-13 powder catalysts were prepared by co-exchange method and stepwise exchange method.It is found that the NH_(3)-SCR activity,N_(2) selectivity,hydrothermal stability and sulfur resistance of Cu/SSZ-13 are promoted by introducing a minority of Mn(0.15%to 0.23%(mass))through co-exchange method.Characterization results reveal that the Cu,Mn co-exchange enables the higher amounts of Cu^(2+)active sites,the abundant medium strong and strong acid,the optimized ratio of Lewis acid to Brønsted acid etc.,which are required for a good NH_(3)-SCR catalytic property over broad temperature range and under harsh working environment.Moreover,a monolithic catalyst was prepared by impregnating a cordierite ceramic support into the coating slurry containing the optimized CuMn/SSZ-13 powder.The diesel engine bench tests show that Cu,Mn co-exchange gives the monolith catalyst a better catalytic property than commercial catalysts.This work provides an important guidance for the rational design of secondary-ion-assisted zeolites applied in NH_(3)-SCR. 展开更多
关键词 MnCu/SSZ-13 Co-exchange ZEOLITE CATALYSIS Selective catalytic reduction
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Preparation and Electrochemical Performance Study of Catalytic Cracking Oil Slurry-based Porous Carbon Materials
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作者 Liu Qi Zhao Gaiju +3 位作者 Liu Xingge Yu Hewei Sun Rongfeng Geng Wenguang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第2期34-45,共12页
Catalytic cracking oil slurry is a by-product of catalytic cracking projects,and the efficient conversion and sustainable utilization of this material are issues of continuous concern in the petroleum refining industr... Catalytic cracking oil slurry is a by-product of catalytic cracking projects,and the efficient conversion and sustainable utilization of this material are issues of continuous concern in the petroleum refining industry.In this study,oxygen-enriched activated carbon is prepared using a one-step KOH activation method with catalytic cracking oil slurry as the raw material.The as-prepared oil slurry-based activated carbon exhibits a high specific surface area of 2102 m^(2)/g,welldefined micropores with an average diameter of 2 nm,and a rich oxygen doping content of 32.97%.The electrochemical performance of the nitrogen-doped porous carbon is tested in a three-electrode system using a 6 mol/L KOH solution as the electrolyte.It achieves a specific capacitance of up to 230 F/g at a current density of 1 A/g.Moreover,the capacitance retention rate exceeds 89%after 10000 charge and discharge cycles,demonstrating excellent cycle stability.This method not only improves the utilization efficiency of industrial fuel waste but also reduces the production cost of supercapacitor electrode materials,thereby providing a simple and effective strategy for the resource utilization of catalytic cracking oil slurries. 展开更多
关键词 catalytic cracking slurry porous carbon SUPERCAPACITOR KOH activation
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Highly Sensitive Ammonia Gas Sensors at Room Temperature Based on the Catalytic Mechanism of N,C Coordinated Ni Single-Atom Active Center
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作者 Wenjing Quan Jia Shi +10 位作者 Min Zeng Wen Lv Xiyu Chen Chao Fan Yongwei Zhang Zhou Liu Xiaolu Huang Jianhua Yang Nantao Hu Tao Wang Zhi Yang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第12期515-531,共17页
Significant challenges are posed by the limitations of gas sensing mechanisms for trace-level detection of ammonia(NH3).In this study,we propose to exploit single-atom catalytic activation and targeted adsorption prop... Significant challenges are posed by the limitations of gas sensing mechanisms for trace-level detection of ammonia(NH3).In this study,we propose to exploit single-atom catalytic activation and targeted adsorption properties to achieve highly sensitive and selective NH3 gas detection.Specifically,Ni singleatom active sites based on N,C coordination(Ni-N-C)were interfacially confined on the surface of two-dimensional(2D)MXene nanosheets(Ni-N-C/Ti_(3)C_(2)Tx),and a fully flexible gas sensor(MNPE-Ni-N-C/Ti_(3)C_(2)Tx)was integrated.The sensor demonstrates a remarkable response value to 5 ppm NH3(27.3%),excellent selectivity for NH3,and a low theoretical detection limit of 12.1 ppb.Simulation analysis by density functional calculation reveals that the Ni single-atom center with N,C coordination exhibits specific targeted adsorption properties for NH3.Additionally,its catalytic activation effect effectively reduces the Gibbs free energy of the sensing elemental reaction,while its electronic structure promotes the spill-over effect of reactive oxygen species at the gas-solid interface.The sensor has a dual-channel sensing mechanism of both chemical and electronic sensitization,which facilitates efficient electron transfer to the 2D MXene conductive network,resulting in the formation of the NH3 gas molecule sensing signal.Furthermore,the passivation of MXene edge defects by a conjugated hydrogen bond network enhances the long-term stability of MXene-based electrodes under high humidity conditions.This work achieves highly sensitive room-temperature NH3 gas detection based on the catalytic mechanism of Ni single-atom active center with N,C coordination,which provides a novel gas sensing mechanism for room-temperature trace gas detection research. 展开更多
关键词 Gas sensor Single atom catalytic activation Targeted adsorption End-sealing passivation
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Syntheses,crystal structures,and catalytic properties of three zinc(Ⅱ),cobalt(Ⅱ)and nickel(Ⅱ)coordination polymers constructed from 5⁃(4⁃carboxyphenoxy)nicotinic acid
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作者 LING Weizhong CHEN Xiangyun +2 位作者 LIU Wenjing HUANG Yingkai LI Yu 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第9期1803-1810,共8页
Three zinc(Ⅱ),cobalt(Ⅱ),and nickel(Ⅱ)coordination polymers,namely[Zn(μ^(3-)cpna)(μ-dpea)_(0.5)]_(n)(1),[Co(μ^(3-)cpna)(μ-dpey)_(0.5)]_(n)(2),and[Ni(μ^(3-)cpna)(μ-dpey)_(0.5)(H_(2)O)]_(n)(3),have been construc... Three zinc(Ⅱ),cobalt(Ⅱ),and nickel(Ⅱ)coordination polymers,namely[Zn(μ^(3-)cpna)(μ-dpea)_(0.5)]_(n)(1),[Co(μ^(3-)cpna)(μ-dpey)_(0.5)]_(n)(2),and[Ni(μ^(3-)cpna)(μ-dpey)_(0.5)(H_(2)O)]_(n)(3),have been constructed hydrothermally using H_(2)cpna(5-(4-carboxyphenoxy)nicotinic acid),dpea(1,2-di(4-pyridyl)ethane),dpey(1,2-di(4-pyridyl)ethylene),and zinc,cobalt,and nickel chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and single-crystal X-ray diffraction analyses.Single-crystal X-ray diffraction analyses revealed that three compounds crystallize in the triclinic system,space group P1.Compounds 1-3 show 2D layer structures.The catalytic activities in the Knoevenagel condensation reaction of these compounds were investigated.Compounds 1 and 2 exhibit effective catalytic activities in the Knoevenagel condensa-tion reaction at room temperature.For this reaction,various parameters were optimized,followed by the investiga-tion of the substrate scope.CCDC:2335676,1;2335677,2;2335678,3. 展开更多
关键词 coordination polymer dicarboxylic acid catalytic property Knoevenagel condensation reaction
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Catalytically altering the redox pathway of sulfur in propylene carbonate electrolyte using dual-nitrogen/oxygen-containing carbon
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作者 Linghui Yu Heng Zhang +9 位作者 Luyuan Paul Wang Samuel Jun Hoong Ong Shibo Xi Bo Chen Rui Guo Ting Wang Yonghua Du Wei Chen Ovadia Lev Zhichuan J.Xu 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期224-233,共10页
Carbonate electrolytes are one of the most desirable electrolytes for high-energy lithium-sulfur batteries(LSBs)because of their successful implementation in commercial Li-ion batteries.The low-polysulfide-solubility ... Carbonate electrolytes are one of the most desirable electrolytes for high-energy lithium-sulfur batteries(LSBs)because of their successful implementation in commercial Li-ion batteries.The low-polysulfide-solubility feature of some carbonate solvents also makes them very promising for overcoming the shuttle effects of LSBs.However,regular sulfur electrodes experience undesired electrochemical mechanisms in carbonate electrolytes due to side reactions.In this study,we report a catalytic redox mechanism of sulfur in propylene carbonate(PC)electrolyte based on a compari-son study.The catalytic mechanism is characterized by the interactions between polysulfides and dual N/O functional groups on the host carbon,which largely prevents side reactions between pol-ysulfides and the carbonate electrolyte.Such a mechanism coupled with the low-polysulfide-solubility feature leads to stable cycling of LSBs in PC electrolyte.Favorable dual N/O functional groups are identified via a density functional theory study.This work provides an alternative route for enabling LSBs in carbonate electrolytes. 展开更多
关键词 Energy storage Lithium-sulfur battery catalytic redox reaction Porous carbon Carbonate electrolyte
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Catalytic Effect of Transition Metal Complexes of Triaminoguanidine on the Thermolysis of Energetic NC/DEGDN Composite
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作者 Mohammed Dourari Ahmed Fouzi Tarchoun +4 位作者 Djalal Trache Amir Abdelaziz Roufaida Tiliouine Tessnim Barkat Weiqiang Pang 《火炸药学报》 EI CAS CSCD 北大核心 2024年第3期209-219,I0003,共12页
The transition metal complexes of triaminoguanidine(TAG-M,where M=Cobalt(Co)or Iron(Fe))have been prepared.The catalytic effect of these complexes on the thermolysis of energetic composite based on nitrocellulose and ... The transition metal complexes of triaminoguanidine(TAG-M,where M=Cobalt(Co)or Iron(Fe))have been prepared.The catalytic effect of these complexes on the thermolysis of energetic composite based on nitrocellulose and diethylene glycol dinitrate,has been investigated.Extensive characterization of the resulting energetic composites was carried out using scanning electron microscopy(SEM),X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),and differential scanning calorimetry(DSC).Isoconversional kinetic analysis was performed to determine the Arrhenius parameters associated with the thermolysis of the elaborated energetic formulations.It is found that TAG-M complexes have strong catalytic effect on the thermo-kinetic decomposition of NC/DEGDN by decreasing the apparent activation energy and significantly increased the total heat release.The models that govern the decomposition processes are also studied,and it is revealed that different reaction processes are accomplished by introduction metal complexes of triaminoguanidine.Overall,this study serves as a valuable reference for future research focused on the investigation of catalytic combustion features of solid propellants. 展开更多
关键词 triaminoguanidine transition metal complexes NITROCELLULOSE diethylene glycol dinitrate catalytic effect
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Preparation of PrFe_(x)Co_(1-x)O_(3)/Mt catalyst and study on degradation of 2-hydroxybenzoic acid wastewater by catalytic wet peroxide oxidation
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作者 Binxia Zhao Yijia Gao +3 位作者 Tiancheng Hun Xiaoxiao Fan Nan Shao Xiaoqian Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期286-297,共12页
In this study,the perovskite nanocomposite PrFe_(x)Co_(1-x)O_(3)(Pr(S))was successfully synthesized by the sol-gel method;PrFe_(x)Co_(1-x)O_(3)/Al-pillared montmorillonite(Pr(S)/Mt)catalysts were prepared by impregnat... In this study,the perovskite nanocomposite PrFe_(x)Co_(1-x)O_(3)(Pr(S))was successfully synthesized by the sol-gel method;PrFe_(x)Co_(1-x)O_(3)/Al-pillared montmorillonite(Pr(S)/Mt)catalysts were prepared by impregnation(D)method and solid-melting(G)method,respectively,with Pr(S)as the active component and Al-pillared montmorillonite as the carrier.The catalysts were applied to treat the 2-hydroxybenzoic acid(2-HA)-simulated wastewater by catalytic wet peroxide oxidation(CWPO)technique,and the chemical oxygen demand(COD)removal rate and the 2-HA degradation rate were used as indicators to evaluate the catalytic performance.The results of the experiment indicated that the solid-melting method was more conducive to preparing the catalyst when the Co/Fe molar ratio of 7:3 and the optimal structural properties of the catalysts were achieved.The influence of operating parameters,including reaction temperature,catalyst dosage,H_(2)O_(2)dosage,pH,and initial 2-HA concentration,were optimized for the degradation of 2-HA by CWPO.The results showed that 97.64%of 2-HA degradation and 75.23%of COD removal rate were achieved under more suitable experimental conditions.In addition,after the catalyst was used five times,the degradation rate of 2-HA could still reach 76.93%,which implied the high stability and reusability of the catalyst.The high catalytic activity of the catalyst was due to the doping of Co into PrFeO_(3),which could promote the generation of HO·,and the high stability could be attributed to the loading of Pr(S)onto Al-Mt,which reduced the leaching of reactive metals.The study of reaction mechanism and kinetics showed that the whole degradation process conformed to the pseudo-firstorder kinetic equation,and the Langmuir-Hinshelwood method was applied to demonstrate that catalysis was dominant in the degradation process. 展开更多
关键词 MONTMORILLONITE PEROVSKITE catalytic wet peroxide oxidation(CWPO) 2-Hydroxybenzoic acid
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Preparation of Modified UiO-66 Catalyst and Its Catalytic Performance for NH_(3)-SCR Denitration
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作者 吴彦霞 梁海龙 +2 位作者 CHEN Yufeng HU Liming WANG Chunpeng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期261-267,共7页
Zirconium-based metal-organic framework UiO-66 was successfully prepared by solvothermal method,and UiO-66 was modified by adding regulators such as formic acid,acetic acid,and hydrochloric acid.The NH_(3)-SCR reactiv... Zirconium-based metal-organic framework UiO-66 was successfully prepared by solvothermal method,and UiO-66 was modified by adding regulators such as formic acid,acetic acid,and hydrochloric acid.The NH_(3)-SCR reactivity of the samples was evaluated by the denitration activity evaluation system,and the UiO-66 and the regulator-modified UiO-66 were characterized by XRD,SEM,BET,FTIR,TG,NH_(3)-TPD,etc.,the effects of regulator types on the structure and properties of UiO-66 were investigated.The experimental results show that,after adding the modifier,the morphology of UiO-66 changes from irregular quadrilateral with serious agglomeration to particles with regular crystal shape and good dispersibility,and the crystal morphology of the catalyst is improved.In addition,after adding the modifier,UiO-66 has a larger specific surface area and stronger surface acidity,which optimizes the catalytic performance of UiO-66.The catalytic performance test results of NH_(3)-SCR show that the low-temperature activity of UiO-66 is poor,and it only shows a certain catalytic activity at higher temperatures.The catalytic activity of UiO-66 was significantly improved after adding the regulator.Among them,the UiO-66-HCl modified with hydrochloric acid had the best catalytic activity,and the denitration rate reached 70%when the denitration temperature was 380℃. 展开更多
关键词 UiO-66 catalyst catalytic denitration NH_(3)-SCR MODIFIED
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Four-channel catalytic micro-reactor based on alumina hollow fiber membrane for efficient catalytic oxidation of CO
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作者 Baichuan Xu Bin Wang Tao Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第7期140-147,共8页
The traditional automotive catalytic converter using commercial ceramic honeycomb carriers has many problems such as high back pressure,low engine efficiency,and high usage of precious metals.This study proposes a fou... The traditional automotive catalytic converter using commercial ceramic honeycomb carriers has many problems such as high back pressure,low engine efficiency,and high usage of precious metals.This study proposes a four-channel catalytic micro-reactor based on alumina hollow fiber membrane,which uses phase inversion method for structural molding and regulation.Due to the advantages of its carrier,it can achieve lower ignition temperature under low noble metal loading.With Pd/CeO_(2) at a loading rate of 2.3%(mass),the result showed that the reaction ignition temperature is even less than 160℃,which is more than 90℃ lower than the data of commercial ceramic substrates under similar catalyst loading and airspeed conditions.The technology in turn significantly reduces the energy consumption of the reaction.And stability tests were conducted under constant conditions for 1000 h,which proved that this catalytic converter has high catalytic efficiency and stability,providing prospects for the design of innovative catalytic converters in the future. 展开更多
关键词 catalytic converter Precious metal catalyst Phase inversion method Hollow fiber membrane CO oxidation
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Catalytic effect in lithium metal batteries: From heterogeneous catalyst to homogenous catalyst
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作者 Haining Fan Xuan-Wen Gao +3 位作者 Hailong Xu Yichun Ding Shi-Xue Dou Wen-Bin Luo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期305-326,I0008,共23页
Lithium metal batteries are regarded as prominent contenders to address the pressing needs owing to the high theoretical capacity.Toward the broader implementation,the primary obstacle lies in the intricate multi-elec... Lithium metal batteries are regarded as prominent contenders to address the pressing needs owing to the high theoretical capacity.Toward the broader implementation,the primary obstacle lies in the intricate multi-electron,multi-step redox reaction associated with sluggish conversion kinetics,subsequently giving rise to a cascade of parasitic issues.In order to smooth reaction kinetics,catalysts are widely introduced to accelerate reaction rate via modulating the energy barrier.Over past decades,a large amount of research has been devoted to the catalyst design and catalytic mechanism exploration,and thus the great progress in electrochemical performance has been realized.Therefore,it is necessary to make a comprehensive review toward key progress in catalyst design and future development pathway.In this review,the basic mechanism of lithium metal batteries is provided along with corresponding advantages and existing challenges detailly described.The main catalysts employed to accelerate cathode reaction with emphasis on their catalytic mechanism are summarized as well.Finally,the rational design and innovative direction toward efficient catalysts are suggested for future application in metal-sulfur/gas battery and beyond.This review is expected to drive and benefit future research on rational catalyst design with multi-parameter synergistic impacts on the activity and stability of next-generation metal battery,thus opening new avenue for sustainable solution to climate change,energy and environmental issues,and the potential industrial economy. 展开更多
关键词 Energy storage and conversion Metal battery Sulfur battery Air battery catalytic effect Heterogeneous catalyst Homogeneous catalyst
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