期刊文献+
共找到207,631篇文章
< 1 2 250 >
每页显示 20 50 100
In-situ carbonization approach for the binder-free Ir-dispersed ordered mesoporous carbon hydrogen evolution electrode 被引量:1
1
作者 Yanghua He Jinming Xu +5 位作者 Fanan Wang Xiaochen Zhao Guangzhao Yin Qing Mao Yanqiang Huang Tao Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第6期1140-1146,共7页
A binder-free Ir-dispersed ordered mesoporous carbon(Ir-OMC) catalytic electrode has been prepared through a designed in-situ carbonization method, which involves coating resorcinol and formaldehyde mixtures with ir... A binder-free Ir-dispersed ordered mesoporous carbon(Ir-OMC) catalytic electrode has been prepared through a designed in-situ carbonization method, which involves coating resorcinol and formaldehyde mixtures with iridium precursors onto the three-dimensional nickel foam framework, followed by insitu calcination in Natmosphere at 800 ℃ for 3 h. This electrode shows a large surface area, ordered mesoporous structure and homogeneous distribution of metal nanoparticles. It presents good activity and stability towards hydrogen evolution reaction, which is attributed to the efficient mass and electron transport from the intimate contact among Ir nanoparticles, ordered mesoporous carbon matrix and 3 D conductive substrate. We hope that this in-situ carbonization synthetic route can also be applied to design more high-performance catalysts for water splitting, fuel cells and other clean energy devices. 展开更多
关键词 in-situ carbonization Ordered mesoporous carbon HER
下载PDF
Facile synthesis of hierarchically porous carbons by controlling the initial oxygen concentration in-situ carbonization of ZIF-8 for efficient water treatment 被引量:1
2
作者 Na Zhou Yan Du +1 位作者 Chunyu Wang Rizhi Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第12期2523-2530,共8页
The state-of-the-art approaches for adjusting the structural characteristics of porous carbons are the aftertreatments, which are complicated and time consuming. In this work, a facile approach was developed, i.e., co... The state-of-the-art approaches for adjusting the structural characteristics of porous carbons are the aftertreatments, which are complicated and time consuming. In this work, a facile approach was developed, i.e., controlling the initial oxygen concentration in-situ during the direct carbonization of zeolitic imidazole framework-8(ZIF-8), to adjust the pore structure and prepare hierarchically porous carbons. The introduction of oxygen can significantly affect the crystalline and pore structures of porous carbons, and promote the pore widening and the formation of mesopores. An appropriate initial oxygen concentration can notably enhance the surface area and mesopore volume of porous carbon, and then improve the adsorption capacity toward methylene blue(MB) dye from water by 3.4 times. The developed approach is more efficient at lower carbonization temperature.Moreover, the introduction of oxygen can increase the ratio of HO\\C_O groups on the carbon surface, leading to enhanced interaction with MB molecules and higher adsorption capacity toward MB. The as-prepared porous carbons exhibit superior adsorption capacities toward MB dye as compared to the reported ZIF-8 derived carbons. These findings would aid the development of porous carbon materials with high performance. 展开更多
关键词 POROUS carbon ZIF-8 carbonization Oxygen Adsorption Water treatment
下载PDF
Controllable Condensation of Aromatics and Its Mechanisms in Carbonization
3
作者 Fan Xi Wang Chunlu +3 位作者 Luo Yang Ren Qiang Shen Haiping Long Jun 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第1期34-46,共13页
In order to obtain liquefied products with higher yields of aromatic molecules to produce mesophase pitch,a good understanding of the relevant reaction mechanisms is required.Reactive molecular dynamics simulations we... In order to obtain liquefied products with higher yields of aromatic molecules to produce mesophase pitch,a good understanding of the relevant reaction mechanisms is required.Reactive molecular dynamics simulations were used to study the thermal reactions of pyrene,1-methylpyrene,7,8,9,10-tetrahydrobenzopyrene,and mixtures of pyrene with 1-octene,cyclohexene,or styrene.The reactant conversion rates,reaction rates,and product distributions were calculated and compared,and the mechanisms were analyzed and discussed.The results demonstrated that methyl and naphthenic structures in aromatics might improve the conversion rates of reactants in hydrogen transfer processes,but their steric hindrances prohibited the generation of high polymers.The naphthenic structures could generate more free radicals and presented a more obvious inhibition effect on the condensation of polymers compared with the methyl side chains.It was discovered that when different olefins were mixed with pyrene,1-octene primarily underwent pyrolysis reactions,whereas cyclohexene mainly underwent hydrogen transfer reactions with pyrene and styrene,mostly producing superconjugated biradicals through condensation reactions with pyrene.In the mixture systems,the olefins scattered aromatic molecules,hindering the formation of pyrene trimers and higher polymers.According to the reactive molecular dynamics simulations,styrene may enhance the yield of dimer and enable the controlled polycondensation of pyrene. 展开更多
关键词 carbonization controllable condensation AROMATICS MECHANISMS molecular simulation
下载PDF
In-situ construction of abundant active centers on hierarchically porous carbon electrode toward high-performance phosphate electrosorption: Synergistic effect of electric field and capture sites
4
作者 Peng Zhang Fukuan Li +6 位作者 Mingming He Silu Huo Xueli Zhang Benqiang Cen Dezhi Fang Kexun Li Hao Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期126-137,共12页
Phosphate removal is crucial for eutrophication control and water quality improvement.Electro-assisted adsorption,an eco-friendly elec-trosorption process,exhibited a promising potential for wastewater treatment.Howev... Phosphate removal is crucial for eutrophication control and water quality improvement.Electro-assisted adsorption,an eco-friendly elec-trosorption process,exhibited a promising potential for wastewater treatment.However,there are few works focused on phosphate electro-sorption,and reported electrodes cannot attach satisfactory removal capacities and rates.Herein,electro-assisted adsorption of phosphate via in-situ construction of La active centers on hierarchically porous carbon(LaPC)has been originally demonstrated.The resulted LaPC composite not only possessed a hierarchically porous structure with uniformly dispersed La active sites,but also provided good conductivity for interfacial electron transfer.The LaPC electrode achieved an ultrahigh phosphate electrosorption capability of 462.01 mg g^(-1) at 1 V,outperforming most existing electrodes.The superior phosphate removal performance originates from abundant active centers formed by the coupling of electricfield and capture sites.Besides,the stability and selectivity toward phosphate capture were maintained well even under comprehensive conditions.Moreover,a series of kinetics and isotherms models were employed to validate the electrosorption process.This work demonstrates a deep understanding and promotes a new level of phosphate electrosorption. 展开更多
关键词 Electro-assisted adsorption ELECTROSORPTION Phosphate removal Active centers MOF-derived carbon
下载PDF
Cross-upgrading of biomass hydrothermal carbonization and pyrolysis for high quality blast furnace injection fuel production:Physicochemical characteristics and gasification kinetics analysis
5
作者 Han Dang Runsheng Xu +2 位作者 Jianliang Zhang Mingyong Wang Jinhua Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期268-281,共14页
The paper proposes a biomass cross-upgrading process that combines hydrothermal carbonization and pyrolysis to produce high-quality blast furnace injection fuel.The results showed that after upgrading,the volatile con... The paper proposes a biomass cross-upgrading process that combines hydrothermal carbonization and pyrolysis to produce high-quality blast furnace injection fuel.The results showed that after upgrading,the volatile content of biochar ranged from 16.19%to 45.35%,and the alkali metal content,ash content,and specific surface area were significantly reduced.The optimal route for biochar pro-duction is hydrothermal carbonization-pyrolysis(P-HC),resulting in biochar with a higher calorific value,C=C structure,and increased graphitization degree.The apparent activation energy(E)of the sample ranges from 199.1 to 324.8 kJ/mol,with P-HC having an E of 277.8 kJ/mol,lower than that of raw biomass,primary biochar,and anthracite.This makes P-HC more suitable for blast furnace injection fuel.Additionally,the paper proposes a path for P-HC injection in blast furnaces and calculates potential environmental benefits.P-HC of-fers the highest potential for carbon emission reduction,capable of reducing emissions by 96.04 kg/t when replacing 40wt%coal injec-tion. 展开更多
关键词 blast furnace injection BIOMASS cross-upgrading hydrothermal carbonization PYROLYSIS physicochemical properties gasific-ation properties
下载PDF
A thermodynamic view on the in-situ carbon dioxide reduction by biomass-derived hydrogen during calcium carbonate decomposition
6
作者 Peng Jiang Hao Zhang +5 位作者 Guanhan Zhao Lin Li Tuo Ji Liwen Mu Xiaohua Lu Jiahua Zhu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期231-240,共10页
In the carbonate industry,deep decarbonization strategies are necessary to effectively remediate CO_(2).These strategies mainly include both sustainable energy supplies and the conversion of CO_(2)in downstream proces... In the carbonate industry,deep decarbonization strategies are necessary to effectively remediate CO_(2).These strategies mainly include both sustainable energy supplies and the conversion of CO_(2)in downstream processes.This study developed a coupled process of biomass chemical looping H2 production and reductive calcination of CaCO_(3).Firstly,a mass and energy balance of the coupled process was established in Aspen Plus.Following this,process optimization and energy integration were implemented to provide optimized operation conditions.Lastly,a life cycle assessment was carried out to assess the carbon footprint of the coupled process.Results reveal that the decomposition temperature of CaCO_(3)in an H_(2)atmosphere can be reduced to 780℃(generally around 900℃),and the conversion of CO_(2)from CaCO_(3)decomposition reached 81.33%with an H2:CO ratio of 2.49 in gaseous products.By optimizing systemic energy through heat integration,an energy efficiency of 86.30%was achieved.Additionally,the carbon footprint analysis revealed that the process with energy integration had a low global warming potential(GWP)of-2.624 kg·kg^(-1)(CO_(2)/CaO).Conclusively,this work performed a systematic analysis of introducing biomass-derived H_(2)into CaCO_(3)calcination and demonstrated the positive role of reductive calcination using green H_(2)in mitigating CO_(2)emissions within the carbonate industry. 展开更多
关键词 BIOMASS CaCO_(3)reductive calcination Chemical looping Hydrogen production carbon footprint Thermodynamics process
下载PDF
Accelerating H^(*)desorption of hollow Mo_(2)C nanoreactor via in-situ grown carbon dots for electrocatalytic hydrogen evolution
7
作者 Mengmeng Liu Yuanyuan Jiang +3 位作者 Zhuwei Cao Lulu Liu Hong Chen Sheng Ye 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期464-471,共8页
Molybdenum carbide(Mo_(2)C)is a promising non-noble metal electrocatalyst with electronic structures similar to Pt for hydrogen evolution reaction(HER).However,strong H^(*)adsorption at the Mo sites hinders the improv... Molybdenum carbide(Mo_(2)C)is a promising non-noble metal electrocatalyst with electronic structures similar to Pt for hydrogen evolution reaction(HER).However,strong H^(*)adsorption at the Mo sites hinders the improvement of HER performance.Here,we synthesized monodisperse hollow Mo_(2)C nanoreactors,in which the carbon dots(CD)were in situ formed onto the surface of Mo_(2)C through carburization reactions.According to finite element simulation and analysis,the CD@Mo_(2)C possesses better mesoscale diffusion properties than Mo_(2)C alone.The optimized CD@Mo_(2)C nanoreactor demonstrates superior HER performance in alkaline electrolyte with a low overpotential of 57 mV at 10 mA cm^(−2),which is better than most Mo_(2)C-based electrocatalysts.Moreover,CD@Mo_(2)C exhibits excellent electrochemical stability during 240 h,confirmed by operando Raman and X-ray diffraction(XRD).Density functional theory(DFT)calculations show that carbon dots cause the d-band center of CD@Mo_(2)C to shift away from Fermi level,promoting water dissociation and the desorption of H^(*).This study provides a reasonable strategy towards high-activity Mo-based HER eletrocatalysts by modulating the strength of Mo–H bonds. 展开更多
关键词 Mo_(2)C nanoreactor carbon dots H^(*)desorption Electrocatalytic hydrogen evolution
下载PDF
Breaking the temperature limit of hydrothermal carbonization of lignocellulosic biomass by decoupling temperature and pressure 被引量:4
8
作者 Shijie Yu Xiaoxiao Yang +2 位作者 Qinghai Li Yanguo Zhang Hui Zhou 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第4期1216-1227,共12页
Hydrothermal carbonization(HTC) of lignocellulosic biomass is a promising technology for the production of carbon materials with negative carbon emissions. However, the high reaction temperature and energy consumption... Hydrothermal carbonization(HTC) of lignocellulosic biomass is a promising technology for the production of carbon materials with negative carbon emissions. However, the high reaction temperature and energy consumption have limited the development of HTC technology. In conventional batch reactors, the temperature and pressure are typically coupled at saturated states. In this study, a decoupled temperature and pressure hydrothermal(DTPH) reaction system was developed to decrease the temperature of the HTC reaction of lignocellulosic biomass(rice straw and poplar leaves). The properties of hydrochars were analyzed by scanning electron microscopy(SEM), Fourier transform infrared(FTIR) spectroscopy, X-ray photoelectron spectroscopy(XPS), Raman spectroscopy, X-ray diffraction(XRD), thermogravimetric analyzer(TGA), etc. to propose the reaction mechanism. The results showed that the HTC reaction of lignocellulosic biomass could be realized at a low temperature of 200℃ in the DTPH process, breaking the temperature limit(230℃) in the conventional process. The DTPH method could break the barrier of the crystalline structure of cellulose in the lignocellulosic biomass with high cellulose content, realizing the carbonization of cellulose and hemicellulose with the dehydration, unsaturated bond formation, and aromatization. The produced hydrochar had an appearance of carbon microspheres, with high calorific values, abundant oxygen-containing functional groups, a certain degree of graphitization, and good thermal stability. Cellulose acts not only as a barrier to protect itself and hemicellulose from decomposition, but also as a key precursor for the formation of carbon microspheres. This study shows a promising method for synthesizing carbon materials from lignocellulosic biomass with a carbon-negative effect. 展开更多
关键词 BIOMASS LIGNOCELLULOSE Hydrothermal treatment Hydrochar carbon materials
下载PDF
Influence of carbonization temperature on cobalt-based nitrogendoped carbon nanopolyhedra derived from ZIF-67 for nonoxidative propane dehydrogenation 被引量:1
9
作者 Yu-Ming Li Zi-Ye Liu +5 位作者 Qi-Yang Zhang Ya-Jun Wang Guo-Qing Cui Zhen Zhao Chun-Ming Xu Gui-Yuan Jiang 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期559-568,共10页
Propylene is a significant basic material for petrochemicals such as polypropylene,propylene oxide,etc.With abundant propane supply from shale gas,propane dehydrogenation(PDH)becomes extensively attractive as an on-pu... Propylene is a significant basic material for petrochemicals such as polypropylene,propylene oxide,etc.With abundant propane supply from shale gas,propane dehydrogenation(PDH)becomes extensively attractive as an on-purpose propylene production route in recent years.Nitrogen-doped carbon(NC)nanopolyhedra supported cobalt catalysts were synthesized in one-step of ZIF-67 pyrolysis and investigated further in PDH.XPS,TEM and N_(2) adsorption-desorption were used to study the influence of carbonization temperature on as-prepared NC supported cobalt catalysts.The temperature is found to affect the cobalt phase and nitrogen species of the catalysts.And the positive correlation was established between Co0 proportion and space time yield of propylene,indicating that the modulation of carbonization temperature could be important for catalytic performance. 展开更多
关键词 Propane dehydrogenation ZIF-67 Nitrogen-doped carbon COBALT
下载PDF
Recycling Carbon Resources from Waste PET to Reduce Carbon Dioxide Emission:Carbonization Technology Review and Perspective 被引量:1
10
作者 Xing Zhou Qi Wang +6 位作者 Sai Feng Jingrui Deng Keming Zhu Yun Xing Xiaolian Meng Xiaojun Wang Lu Li 《Journal of Renewable Materials》 SCIE EI 2023年第5期2085-2108,共24页
Greenhouse gas emissions from waste plastics have caused global warming all over the world,which has been a central threat to the ecological environment for humans,flora and fauna.Among waste plastics,waste polyethyle... Greenhouse gas emissions from waste plastics have caused global warming all over the world,which has been a central threat to the ecological environment for humans,flora and fauna.Among waste plastics,waste polyethylene terephthalate(PET)is attractive due to its excellent stability and degradation-resistant.Therefore,merging China’s carbon peak and carbon neutrality goals would be beneficial.In this review,we summarize the current state-of-the-art of carbon emission decrease from a multi-scale perspective technologically.We suggest that the carbon peak for waste PET can be achieved by employing the closed-loop supply chain,including recycling,biomass utilization,carbon capture and utilization.Waste PET can be a valuable and renewable resource in the whole life cycle.Undoubtedly,all kinds of PET plastics can be ultimately converted into CO_(2),which can also be feedstock for various kinds of chemical products,including ethyl alcohol,formic acid,soda ash,PU,starch and so on.As a result,the closed-loop supply chain can help the PET plastics industry drastically reduce its carbon footprint. 展开更多
关键词 carbon peak emission PET plastic RECYCLING waste management
下载PDF
Restoration of reservoir diagenesis and hydrocarbon accumulation process by calcite in-situ U-Pb dating and fluid inclusion analysis: A case study on Cretaceous Qingshuihe Formation in Gaoquan Structure, southern Junggar Basin, NW China 被引量:1
11
作者 GUI Lili ZHUO Qingong +7 位作者 LU Xuesong YANG Wenxia CHEN Weiyan WU Hai FAN Junjia HE Yinjun CAO Rizhou YU Xiaoqing 《Petroleum Exploration and Development》 SCIE 2023年第6期1386-1397,共12页
The complexity of diagenesis and hydrocarbon accumulation in the deep reservoirs in southern Junggar Basin restricts hydrocarbon exploration in the lower reservoir assemblage. The lithofacies and diagenesis of reservo... The complexity of diagenesis and hydrocarbon accumulation in the deep reservoirs in southern Junggar Basin restricts hydrocarbon exploration in the lower reservoir assemblage. The lithofacies and diagenesis of reservoirs in the Cretaceous Qingshuihe Formation in the Gaoquan structure of the Sikeshu Sag, southern Junggar Basin were analyzed. On this basis, the thermal history was calibrated using calcite in-situ U-Pb dating and fluid inclusion analysis to depict the hydrocarbon accumulation process in the Gaoquan structure. The results show that the Qingshuihe reservoir experienced two phases of calcite cementation and three phases of hydrocarbon charging. The calcite cements are dated to be (122.1±6.4) Ma, (14.4±1.0) Ma - (14.2±0.3) Ma. The hydrocarbon charging events occurred at around 14.2-30.0 Ma (low-mature oil), 14.2 Ma (mature oil), and 2 Ma (high-mature gas). The latter two phases of hydrocarbon charging contributed dominantly to the formation of reservoir. Due to the S-N compressive thrust activity during the late Himalayan period since 2 Ma, the traps in the Gaoquan structure were reshaped, especially the effective traps which developed in the main reservoir-forming period were decreased significantly in scale, resulting in weak hydrocarbon shows in the middle-lower part of the structure. This indicates that the effective traps in key reservoir-forming period controlled hydrocarbon enrichment and distribution in the lower reservoir assemblage. Calcite U-Pb dating combined with fluid inclusion analysis can help effectively describe the complex diagenesis and hydrocarbon accumulation process in the central-west part of the basin. 展开更多
关键词 fluid inclusion calcite in-situ U-Pb dating diagenetic sequence hydrocarbon accumulation timing Sikeshu Sag southern Junggar Basin CRETACEOUS Qingshuihe Formation
下载PDF
In-situ hydrocarbon formation and accumulation mechanisms of micro- and nano-scale pore-fracture in Gulong shale, Songliao Basin, NE China 被引量:1
12
作者 WANG Xiaojun CUI Baowen +5 位作者 FENG Zihui SHAO Hongmei HUO Qiuli ZHANG Bin GAO Bo ZENG Huasen 《Petroleum Exploration and Development》 SCIE 2023年第6期1269-1281,共13页
By conducting experimental analyses, including thermal pyrolysis, micro-/nano-CT, argon-ion polishing field emission scanning electron microscopy (FE-SEM), confocal laser scanning microscopy (CLSM), and two-dimensiona... By conducting experimental analyses, including thermal pyrolysis, micro-/nano-CT, argon-ion polishing field emission scanning electron microscopy (FE-SEM), confocal laser scanning microscopy (CLSM), and two-dimensional nuclear magnetic resonance (2D NMR), the Gulong shale oil in the Songliao Basin was investigated with respect to formation model, pore structure and accumulation mechanism. First, in the Gulong shale, there are a large number of pico-algae, nano-algae and dinoflagellates, which were formed in brackish water environment and constituted the hydrogen-rich oil source materials of shale. Second, most of the oil-generating materials of the Qingshankou Formation shale exist in the form of organo-clay complex. During organic matter thermal evolution, clay minerals had double effects of suppression and catalytic hydrogenation, which expanded shale oil window and increased light hydrocarbon yield. Third, the formation of storage space in the Gulong Shale was related to dissolution and hydrocarbon generation. With the diagenesis, micro-/nano-pores increased, pore diameter decreased and more bedding fractures appeared, which jointly gave rise to the unique reservoir with dual media (i.e. nano-scale pores and micro-scale bedding fractures) in the Gulong shale. Fourth, the micro-/nano-scale oil storage unit in the Gulong shale exhibits independent oil/gas occurrence phase, and shows that all-size pores contain oils, which occur in condensate state in micropores or in oil-gas two phase (or liquid) state in macropores/mesopores. The understanding about Gulong shale oil formation and accumulation mechanism has theoretical and practical significance for advancing continental shale oil exploration in China. 展开更多
关键词 micro- nano-scale oil storage unit hydrocarbon occurrence phase organo-clay complex in-situ hydrocarbon accumulation Gulong shale oil Cretaceous Qingshankou Formation Songliao Basin
下载PDF
A Primary Study on Mechanical Properties of Heat-Treated Wood via in-situ Synthesis of Calcium Carbonate
13
作者 Dianen Liang Zhenhao Ding +8 位作者 Qilin Yan Redžo Hasanagić Leila Fathi Zi Yang Longhao Li Jianbo Wang Houhua Luo Qian Wang Demiao Chu 《Journal of Renewable Materials》 SCIE EI 2023年第1期435-451,共17页
This study aims to improve the value of fast-growing wood and extend the heat-treated wood utilization using inorganic calcium carbonate(CaCO_(3))crystals via an in-situ synthesis method.CaCl_(2)and Na 2CO_(3)solution... This study aims to improve the value of fast-growing wood and extend the heat-treated wood utilization using inorganic calcium carbonate(CaCO_(3))crystals via an in-situ synthesis method.CaCl_(2)and Na 2CO_(3)solutions with a concentration ratio of 1:1 were successively introduced into the thermally modified poplar wood obtained by steam heat treatment(HT)at 200℃for 1.5 and 3 h,resulting in the in-situ synthesis of CaCO_(3)crystals inside the heat-treated wood.The filling effect was best at the concentration of 1.2 mol/L.CaCO_(3)was uniformly distributed in the cell cavities of the heat-treated wood,and some of the crystals were embedded in the fissures of the wood cell walls.The morphology of CaCO_(3)crystals was mainly spherical and rhombic polyhedral.Three main types of CaCO_(3)crystals were calcite,vaterite,and aragonite.The HT of poplar wood at 200℃resulted in degrading the chemical components of the wood cell wall.This degradation led to reduced wood mechanical properties,including the surface hardness(HD),modulus of rupture(MOR),and modulus of elasticity(MOE).After CaCO_(3)was in-situ synthesized in the heat-treated wood,the HD increased by 18.36%and 16.35%,and MOR increased by 14.64%and 8.89%,respectively.Because of the CaCO_(3)synthesization,the char residue of the 200℃heat-treated wood samples increased by 9.31%and the maximum weight loss rate decreased by 19.80%,indicating that the filling with CaCO_(3)cannot only improve the mechanical properties of the heat-treated wood but also effectively enhance its thermal stability. 展开更多
关键词 Heat treatment poplar wood calcium carbonate in-situ synthesis REINFORCEMENT
下载PDF
Revealing sodium storage mechanism of hard carbon anodes through in-situ investigation of mechano-electrochemical coupling behavior
14
作者 Mei Yang Zhenya Luo +5 位作者 Xiao Wang Xinxin Cao Weiguo Mao Yong Pan Cuiying Dai Junan Pan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第11期227-236,I0006,共11页
Hard carbon(HC)is considered a promising anode material for sodium-ion batteries due to its relatively low price and high specific capacity.However,HC still suffers from unclear reaction mechanisms and unsatisfactory ... Hard carbon(HC)is considered a promising anode material for sodium-ion batteries due to its relatively low price and high specific capacity.However,HC still suffers from unclear reaction mechanisms and unsatisfactory cycling stability.The study of mechano-electrochemical coupling behavior by in-situ measurement techniques is expected to understand the sodium storage and degradation mechanisms.In this paper,the strain and stress evolution of HC anodes at different sodiation/desodiation depths and cycles are investigated by combining electrochemical methods,digital image correlation,and theoretical equations.The observation by monitoring the in-situ strain evolution during the redox process supports the“adsorption-intercalation/filling”mechanism in reduction and the“de-filling/de-intercalation-deso rption”mechanism in oxidation.Further studies have demonstrated that the strain and stress of the electrode show periodic changes accompanied by a continuous accumulation of residual stress during cycles,explaining the capacity degradation mechanism of HC from a mechanical perspective.In addition,when the higher current density is applied,the electrodes experience greater strain and stress associated with the Na+insertion rate.This work clarifies the Na-storage mechanism and the mechano-electrochemical coupling mechanism of HC anodes by in-situ strain measurement,which helps optimize and design the anode materials of sodium-ion batteries from the perspective of interface microstructure and multi-field coupling,such as in situ integrated interface structure design. 展开更多
关键词 Hard carbon Sodium storage in-situ strain measurement Digital image correlation Mechano-electrochemical coupling
下载PDF
Boosting high initial coulombic efficiency of hard carbon by in-situ electrochemical presodiation 被引量:1
15
作者 Nannan Qin Yanyan Sun +5 位作者 Chao Hu Sainan Liu Zhigao Luo Xinxin Cao Shuquan Liang Guozhao Fang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期310-316,I0008,共8页
Hard carbon(HC)is a promising anode material for sodium ion batteries(SIBs),whereas inferior initial coulombic efficiency(ICE)severely limits its practical application.In the present work,we propose an in situ electro... Hard carbon(HC)is a promising anode material for sodium ion batteries(SIBs),whereas inferior initial coulombic efficiency(ICE)severely limits its practical application.In the present work,we propose an in situ electrochemical presodiation approach to improve ICE by mixing sodium biphenyl(Na-Bp)dimethoxyethane(DME)solution with DME-based ether electrolyte.A solid electrolyte interface(SEI)could be formed beforehand on the HC electrode and Na^(+)was absorbed to nanopores and graphene stacks,compensating for the sodium loss and preventing electrolyte decomposition during the initial charge and discharge cycle.By this way,the ICE of half-cells was increased to nearly 100%and that of full-cells from 45%to 96%with energy density from 132.9 to 230.5 W h kg^(-1).Our work provides an efficient and facile method for improving ICE,which can potentially promote the practical application of HCbased materials. 展开更多
关键词 Hard carbon In situ presodiation Initial coulombic efficiency Solid electrolyte interface Sodium-ion batteries
下载PDF
Decarbonization options of the iron and steelmaking industry based on a three-dimensional analysis 被引量:1
16
作者 Xin Lu Weijian Tian +3 位作者 Hui Li Xinjian Li Kui Quan Hao Bai 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第2期388-400,共13页
Decarbonization is a critical issue for peaking CO_(2) emissions of energy-intensive industries,such as the iron and steel industry.The decarbonization options of China’s ironmaking and steelmaking sector were discus... Decarbonization is a critical issue for peaking CO_(2) emissions of energy-intensive industries,such as the iron and steel industry.The decarbonization options of China’s ironmaking and steelmaking sector were discussed based on a systematic three-dimensional low-carbon analysis from the aspects of resource utilization(Y),energy utilization(Q),and energy cleanliness which is evaluated by a process general emission factor(PGEF)on all the related processes,including the current blast furnace(BF)-basic oxygen furnace(BOF)integrated process and the specific sub-processes,as well as the electric arc furnace(EAF)process,typical direct reduction(DR)process,and smelting reduction(SR)process.The study indicates that the three-dimensional aspects,particularly the energy structure,should be comprehensively considered to quantitatively evaluate the decarbonization road map based on novel technologies or processes.Promoting scrap utilization(improvement of Y)and the substitution of carbon-based energy(improvement of PGEF)in particular is critical.In terms of process scale,promoting the development of the scrap-based EAF or DR-EAF process is highly encouraged because of their lower PGEF.The three-dimensional method is expected to extend to other processes or industries,such as the cement production and thermal electricity generation industries. 展开更多
关键词 peak CO_(2)emission low carbon management decarbonization option energy-intensity industry ironmaking and steelmaking
下载PDF
Enhancing the Interaction of Carbon Nanotubes by Metal-Organic Decomposition with Improved Mechanical Strength and Ultra-Broadband EMI Shielding Performance 被引量:3
17
作者 Yu-Ying Shi Si-Yuan Liao +7 位作者 Qiao-Feng Wang Xin-Yun Xu Xiao-Yun Wang Xin-Yin Gu You-Gen Hu Peng-Li Zhu Rong Sun Yan-Jun Wan 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期281-294,共14页
The remarkable properties of carbon nanotubes(CNTs)have led to promising applications in the field of electromagnetic inter-ference(EMI)shielding.However,for macroscopic CNT assemblies,such as CNT film,achieving high ... The remarkable properties of carbon nanotubes(CNTs)have led to promising applications in the field of electromagnetic inter-ference(EMI)shielding.However,for macroscopic CNT assemblies,such as CNT film,achieving high electrical and mechanical properties remains challenging,which heavily depends on the tube-tube interac-tions of CNTs.Herein,we develop a novel strategy based on metal-organic decomposition(MOD)to fabricate a flexible silver-carbon nanotube(Ag-CNT)film.The Ag particles are introduced in situ into the CNT film through annealing of MOD,leading to enhanced tube-tube interactions.As a result,the electrical conductivity of Ag-CNT film is up to 6.82×10^(5) S m^(-1),and the EMI shielding effectiveness of Ag-CNT film with a thickness of~7.8μm exceeds 66 dB in the ultra-broad frequency range(3-40 GHz).The tensile strength and Young’s modulus of Ag-CNT film increase from 30.09±3.14 to 76.06±6.20 MPa(~253%)and from 1.12±0.33 to 8.90±0.97 GPa(~795%),respectively.Moreover,the Ag-CNT film exhibits excellent near-field shield-ing performance,which can effectively block wireless transmission.This innovative approach provides an effective route to further apply macroscopic CNT assemblies to future portable and wearable electronic devices. 展开更多
关键词 EMI shielding Mechanical strength carbon nanotubes Metal-organic decomposition Flexibility
下载PDF
Carbon Emission Effects Driven by Evolution of Chinese Dietary Structure from 1987 to 2020 被引量:1
18
作者 ZHU Yuanyuan ZHANG Yan ZHU Xiaohua 《Chinese Geographical Science》 SCIE CSCD 2024年第1期181-194,共14页
Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research ob... Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research object(data excluding Hong Kong,Macao and Taiwan) and used the carbon emission coefficient method to quantitatively measure the food carbon emissions from 1987–2020,then analyzed the carbon emission effects under the evolution of dietary structure.The results showed that during the study period,the Chinese dietary structure gradually changed to a high-carbon consumption pattern.The dietary structure of urban residents developed to a balanced one,while that of rural residents developed to a high-quality one.During the study period,the per capita food carbon emissions and total food consumption of Chinese showed an increasing trend.The per capita food carbon emissions of residents in urban and rural showed an overall upward trend.The total food carbon emissions in urban increased significantly,while that in rural increased first and then decreased.The influence of beef and mutton on carbon emissions is the highest in dietary structure.Compared with the balanced dietary pattern,the food carbon emissions of Chinese residents had not yet reached the peak,but were evolving to a high-carbon consumption pattern. 展开更多
关键词 dietary structure structural evolution carbon emission effects carbon neutrality China
下载PDF
Aboveground carbon sequestration of Cunninghamia lanceolata forests:Magnitude and drivers 被引量:1
19
作者 Chen Wang Shuguang Liu +3 位作者 Yu Zhu Andrew R.Smith Ying Ning Deming Deng 《Forest Ecosystems》 SCIE CSCD 2024年第1期32-41,共10页
Understanding the spatial variation,temporal changes,and their underlying driving forces of carbon sequestration in various forests is of great importance for understanding the carbon cycle and carbon management optio... Understanding the spatial variation,temporal changes,and their underlying driving forces of carbon sequestration in various forests is of great importance for understanding the carbon cycle and carbon management options.How carbon density and sequestration in various Cunninghamia lanceolata forests,extensively cultivated for timber production in subtropical China,vary with biodiversity,forest structure,environment,and cultural factors remain poorly explored,presenting a critical knowledge gap for realizing carbon sequestration supply potential through management.Based on a large-scale database of 449 permanent forest inventory plots,we quantified the spatial-temporal heterogeneity of aboveground carbon densities and carbon accumulation rates in Cunninghamia lanceolate forests in Hunan Province,China,and attributed the contributions of stand structure,environmental,and management factors to the heterogeneity using quantile age-sequence analysis,partial least squares path modeling(PLS-PM),and hot-spot analysis.The results showed lower values of carbon density and sequestration on average,in comparison with other forests in the same climate zone(i.e.,subtropics),with pronounced spatial and temporal variability.Specifically,quantile regression analysis using carbon accumulation rates along an age sequence showed large differences in carbon sequestration rates among underperformed and outperformed forests(0.50 and 1.80 Mg·ha^(-1)·yr^(-1)).PLS-PM demonstrated that maximum DBH and stand density were the main crucial drivers of aboveground carbon density from young to mature forests.Furthermore,species diversity and geotopographic factors were the significant factors causing the large discrepancy in aboveground carbon density change between low-and high-carbon-bearing forests.Hotspot analysis revealed the importance of culture attributes in shaping the geospatial patterns of carbon sequestration.Our work highlighted that retaining largesized DBH trees and increasing shade-tolerant tree species were important to enhance carbon sequestration in C.lanceolate forests. 展开更多
关键词 carbon density carbon accumulation rate Forest age Spatial variation Cultural influence
下载PDF
Carbon nanocages bridged with graphene enable fast kinetics for dual-carbon lithium-ion capacitors 被引量:2
20
作者 Shani Li Yanan Xu +7 位作者 Wenhao Liu Xudong Zhang Yibo Ma Qifan Peng Xiong Zhang Xianzhong Sun Kai Wang Yanwei Ma 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第3期573-583,共11页
Lithium-ion capacitors(LICs) combining the advantages of lithium-ion batteries and supercapacitors are considered a promising nextgeneration energy storage device. However, the sluggish kinetics of battery-type anode ... Lithium-ion capacitors(LICs) combining the advantages of lithium-ion batteries and supercapacitors are considered a promising nextgeneration energy storage device. However, the sluggish kinetics of battery-type anode cannot match the capacitor-type cathode, restricting the development of LICs. Herein, hierarchical carbon framework(HCF) anode material composed of 0D carbon nanocage bridged with 2D graphene network are developed via a template-confined synthesis process. The HCF with nanocage structure reduces the Li^(+) transport path and benefits the rapid Li^(+) migration, while 2D graphene network can promote the electron interconnecting of carbon nanocages. In addition, the doped N atoms in HCF facilitate to the adsorption of ions and enhance the pseudo contribution, thus accelerate the kinetics of the anode. The HCF anode delivers high specific capacity, remarkable rate capability. The LIC pouch-cell based on HCF anode and active HCF(a-HCF) cathode can provide a high energy density of 162 Wh kg^(-1) and a superior power density of 15.8 kW kg^(-1), as well as a long cycling life exceeding 15,000cycles. This study demonstrates that the well-defined design of hierarchical carbon framework by incorporating 0D carbon nanocages and 2D graphene network is an effective strategy to promote LIC anode kinetics and hence boost the LIC electrochemical performance. 展开更多
关键词 Hierarchical carbon framework NANOCAGE ZIF GRAPHENE Lithium-ion capacitors
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部