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Enabling low-cost decentralized power reserves adopting carbon dioxide for green methane exchange in stabilized clathrate adsorbent
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作者 Lucas Hanssens Maarten Houlleberghs +7 位作者 C.Vinod Chandran Geert Watson Sambhu Radhakrishnan Pascal Van Der Voort Joeri F.M.Denayer Christine E.A.Kirschhock Johan A.Martens Eric Breynaert 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期438-443,I0009,共7页
1.Challenges circular methane energy systems In recent decades,methane-based energy systems have rapidly gained traction across the globe because of the increasing availability of low-cost methane production capacity.... 1.Challenges circular methane energy systems In recent decades,methane-based energy systems have rapidly gained traction across the globe because of the increasing availability of low-cost methane production capacity.However,fossil methane production and combustion lead to large greenhouse gas emissions,contributing to climate change[1]. 展开更多
关键词 Long duration energy storage Green methane Carbon neutrality Confined clathrate hydrates CH_(4)/CO_(2) exchange Direct gas exchange
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Hydrogen diffusion in C′_(1) phase clathrate hydrate
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作者 宋姿璇 周子岳 +5 位作者 林演文 石桥 郝勇超 付越群 张志森 吴建洋 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期52-59,共8页
Recently,a new phase C'_(1) H_(2) hydrate was experimentally identified.In this work,the diffusive behaviors of H_(2) in C'_(1)phase clathrate hydrate are explored using classic molecular dynamics(MD)simulatio... Recently,a new phase C'_(1) H_(2) hydrate was experimentally identified.In this work,the diffusive behaviors of H_(2) in C'_(1)phase clathrate hydrate are explored using classic molecular dynamics(MD)simulations.It reveals that the cage occupancy by H_(2) molecule negligibly influences the C'_(1) phase clathrate structure but greatly dictates the diffusion coefficient of H_(2)molecule.Due to the small cage size and small windows connecting the neighboring cages in C'_(1) phase clathrate,nonoccupancy of the neighboring cages is demanded to enable the diffusion of H_(2) molecule that is primarily dominated by hopping mechanism.Moreover,the analysis of diffusive free energy landscape reveals lower energy barrier of H_(2) molecule in C'_(1) phase clathrate hydrate than that of other gases in conventional clathrate hydrates,and that H_(2) molecule travels through the windows between neighboring cages with preferential molecular orientation.This study provides critical physical insights into the diffusion behaviors of H_(2) in the C'_(1) phase clathrate hydrate,and implies that the C'_(1) clathrate hydrate is a promising solid structure for the next-generation H_(2) storage. 展开更多
关键词 clathrate hydrate hydrogen storage DIFFUSION molecular dynamics
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Raman Spectroscopy of Nitrogen Clathrate Hydrates 被引量:1
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作者 刘昌岭 卢海龙 业渝光 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第4期353-358,447,共7页
Nitrogen hydrate samples were synthesized using liquid nitrogen and powder ice at 16 MPa and 253 K. Confocal laser Raman spectroscopy was used to investigate the characteristics of nitrogen clathrate hydrates. The res... Nitrogen hydrate samples were synthesized using liquid nitrogen and powder ice at 16 MPa and 253 K. Confocal laser Raman spectroscopy was used to investigate the characteristics of nitrogen clathrate hydrates. The results show that the Raman peaks of N-N and O-H stretching vibration in nitrogen hydrates are observed at 2322.4 and 3092.1 cm^-1, respectively, which are very similar to those in natural air clathrate hydrates. For comparison, we measured the Raman peaks of N-N stretching vibration both in liquid nitrogen and nitrogen molecules saturated water, which appear at 2326.6 and 2325.0 cm^-1, respectively. The Raman spectroscopic observations on the dissociation process suggest that nitrogen molecules occupy both the large and small cages in nitrogen clathrate hydrates. However, only one Raman peak is observed for N N stretching vibration because the difference of the environment of nitrogen molecules between large and small cages is too small to be differentiated by Raman spectroscopy. 展开更多
关键词 Raman spectroscopy Nitrogen clathrate hydrates Nitrogen bond vibration Raman shift
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可视化技术在分析新型蓄冷材料——笼型化合物(Clathrate)溶解过程中的应用(二)
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作者 陈滨 《流体力学实验与测量》 CSCD 北大核心 2001年第1期6-9,共4页
运用折射率匹配 (Refractive IndexMatching)技术 ,使混浊液内部自然对流的可视化图像速度测量成为可能。但由于来自微粒子的散乱光的影响 ,所得到的速度场出现了少量的误对应现象。为了解决这个问题 ,开发了新的可视化实验组合技术—... 运用折射率匹配 (Refractive IndexMatching)技术 ,使混浊液内部自然对流的可视化图像速度测量成为可能。但由于来自微粒子的散乱光的影响 ,所得到的速度场出现了少量的误对应现象。为了解决这个问题 ,开发了新的可视化实验组合技术———折射率匹配与激光诱导荧光法 (LIF :Laser InducedFluorescence)组合 ,利用不同种类的粒子发光波长不同的特性 ,有效地去除了微粒子的散乱光 ,获得了清晰的示踪粒子的图像。笔者将简要介绍激光诱导荧光法的工作原理及其实验结果。 展开更多
关键词 蓄冷材料 可视化 激光诱导荧光 混浊液 图像速度测量法 笼形化合物 clathrate
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可视化技术在分析新型蓄冷材料——笼型化合物(Clathrate)溶解过程中的应用(一)
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作者 陈滨 《流体力学实验与测量》 CSCD 北大核心 2001年第1期1-5,共5页
混浊液内部的流动 ,由于微粒子之间的相互作用以及因浊度高不易进行内部观察 ,所以无论是分析还是可视化实验都相当困难 ,存在着许多未弄清的问题。通过采用折射率匹配 (Refractive IndexMatching)技术 ,使透明的微粒子与透明的溶媒的... 混浊液内部的流动 ,由于微粒子之间的相互作用以及因浊度高不易进行内部观察 ,所以无论是分析还是可视化实验都相当困难 ,存在着许多未弄清的问题。通过采用折射率匹配 (Refractive IndexMatching)技术 ,使透明的微粒子与透明的溶媒的折射率近乎相同 ,做成一种透明的“混浊液” ,从而使混入其中的示踪粒子的运动轨迹能被摄像机捕捉到 ,并以微粒子的沉降和温度的干涉所引起的流动现象为焦点 ,利用图像速度测量法来处理分析所拍摄到的可视化图像 ,成功地获得了定量的混浊液内部的速度场 ,为进一步揭示混浊液内部自然对流的流动机理提供了实验依据。 展开更多
关键词 笼形化合物 蓄冷材料 可视化 折射率匹配 混浊液 粒子追迹速度测量法 clathrate 溶解过程
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Sponge Effect on Coal Mine Methane Separation Based on Clathrate Hydrate Method 被引量:14
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作者 ZHANG Baoyong CHENG Yuanping WU Qiang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第4期610-614,共5页
The findings were presented from laboratory investigations on the hydrate formation and dissociation processes employed to recover methane from coal mine gas.The separation process of coal mine methane(CMM) was carrie... The findings were presented from laboratory investigations on the hydrate formation and dissociation processes employed to recover methane from coal mine gas.The separation process of coal mine methane(CMM) was carried out at 273.15K under 4.00 MPa.The key process variables of gas formation rate,gas volume stored in hydrate and separation concentration were closely investigated in twelve THF-SDS-sponge-gas systems to verify the sponge effect in these hydrate-based separation processes.The gas volume stored in hydrate is calculated based on the measured gas pressure.The CH4 mole fraction in hydrate phase is measured by gas chromatography to confirm the separation efficiency.Through close examination of the overall results,it was clearly verified that sponges with volumes of 40,60 and 80 cm 3 significantly increase gas hydrate formation rate and the gas volume stored in hydrate,and have little effect on the CH4 mole fraction in hydrate phase.The present study provides references for the application of the kinetic effect of porous sponge media in hydrate-based technology.This will contribute to CMM utilization and to benefit for local and global environment. 展开更多
关键词 coal mine methane separation clathrate hydrate SPONGE porous media mass transfer
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Experimental characterization of guest molecular occupancy in clathrate hydrate cages: A review 被引量:5
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作者 Changhong Yu Litao Chen Baojiang Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第9期2189-2206,共18页
Study on the microscopic structure of clathrate hydrate has made significant progress in the past decades.This review aims to summarize the state of the art of the experimental characterization of guest molecular occu... Study on the microscopic structure of clathrate hydrate has made significant progress in the past decades.This review aims to summarize the state of the art of the experimental characterization of guest molecular occupancy in clathrate hydrate cages,which is an important area of the microscopic structures.The characterizing method and features of different guest molecular,such as hydrocarbon,carbon dioxide,hydrogen and inhibitor/promoter,in different hydrate cages have been extensively reviewed.A comprehensive use of advanced technologies such as X-ray diffraction,Raman spectroscopy and nuclear magnetic resonance may provide better understanding on the compositions and microscopic mechanisms of clathrate hydrate. 展开更多
关键词 clathrate HYDRATE Cage OCCUPANCY Experimental characterization PXRD Raman NMR
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THERMAL CONDUCTIVITY OF THF CLATHRATE HYDRATE FROM 243 K TO 263 K 被引量:5
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作者 HUANG Duzi~(1,2) and FAN Shuanshi~1(~1Center for Gas Hydrate, Guangzhou Institute of Energy Conversion, CAS, Guangzhou, 510070, Guangdong, China ~2 Department of Thermal Science & Energy Engineering, USTC, Hefei, 230036, Anhui, China) 《化工学报》 EI CAS CSCD 北大核心 2003年第z1期71-75,共5页
Using transient plane source technique, we measured THF hydrate thermal conductivity from 243 K to 263 K. The sample THF solution is over saturated in order to avoid the effect of ice. And also to avoid the effect of ... Using transient plane source technique, we measured THF hydrate thermal conductivity from 243 K to 263 K. The sample THF solution is over saturated in order to avoid the effect of ice. And also to avoid the effect of crystal anisotropy, the THF hydrate was crushed to measure. In the test temperature value increases with the temperature increasing. 展开更多
关键词 THF in or IT THERMAL CONDUCTIVITY OF THF clathrate HYDRATE FROM 243 K TO 263 K of that
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Intensification of methane and hydrogen storage inclathrate hydrate and future prospect 被引量:5
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作者 Xuemei Lang Shuanshi Fan YanhongWang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2010年第3期203-209,共7页
Gas hydrate is a new technology for energy gas(methane/hydrogen)storage due to its large capacity of gas storage and safe.But industrial application of hydrate storage process was hindered by someproblems.For methan... Gas hydrate is a new technology for energy gas(methane/hydrogen)storage due to its large capacity of gas storage and safe.But industrial application of hydrate storage process was hindered by someproblems.For methane,the main problems are low formation rateand storage capacity,which can be solved by strengthening mass andheat transfer,such as adding additives,stirring,bubbling,etc.Onekind of additives can change the equilibrium curve to reduce the formation pressure of methane hydrate,and the other kind of additivesis surfactant,which can form micelle with water and increase the interface of water-gas.Dry water has the similar effects on the methanehydrate as surfactant.Additionally,stirring,bubbling,and sprayingcan increase formation rate and storage capacity due to mass transferstrengthened.Inserting internal or external heat exchange also canimprove formation rate because of good heat transfer.For hydrogen,the main difficulties are very high pressure for hydrate formed.Tetrahydrofuran(THF),tetrabutylammonium bromide(TBAB) andtetrabutylammonium fluoride(TBAF) have been proved to be able todecrease the hydrogen hydrate formation pressure significantly. 展开更多
关键词 clathrate hydrate METHANE HYDROGEN formation rate storage capacity
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Accelerated methane storage in clathrate hydrates using surfactantstabilized suspension with graphite nanoparticles 被引量:4
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作者 Liang Yang Xin Wang +4 位作者 Daoping Liu Guomin Cui Binlin Dou Juan Wang Shuqing Hao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第4期1112-1119,共8页
In this study,enhanced kinetics of methane hydrate formation in the sodium dodecyl sulfate(SDS)solution with different concentrations of suspended graphite nanoparticles(GNPs)were investigated at 6.1-9.0 MPa and 274.1... In this study,enhanced kinetics of methane hydrate formation in the sodium dodecyl sulfate(SDS)solution with different concentrations of suspended graphite nanoparticles(GNPs)were investigated at 6.1-9.0 MPa and 274.15 K.The GNPs with rough surfaces and excellent thermal conductivity not only provided a considerable number of microsites for hydrate nucleation but also facilitated the fast hydrate heat transfer in the suspension system.At a relatively low pressure of 6.1 MPa,the suspension with 0.4 wt%of GNPs exhibited the minimum induction time of 22 min and maximum methane uptake of 126.1 cm3·cm-3.However,the methane storage performances of the suspensions with higher and lower concentrations of GNPs were not satisfactory.At the applied pressure,the temperature increase arising from the hydrate heat in the suspension system with the optimized concentration(0.4 wt%)of GNPs was more significant than that in the traditional SDS solution.Furthermore,compared with those of the system without GNPs,enhanced hydration rate and storage capacity were achieved in the suspensions with GNPs,and the storage capacities were increased by 3.9%-17.0%.The promotion effect of GNPs on gas hydrate formation at low pressure is much more obvious than that at high pressure. 展开更多
关键词 methane storage clathrate hydrates formation kinetics SUSPENSION graphite nanoparticles
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Synthesis and high temperature thermoelectric transport properties of Si-based type-Ⅰ clathrates 被引量:3
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作者 邓书康 唐新峰 唐润生 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第7期3084-3089,共6页
N-type Si-based type-Ⅰ clathrates with different Ga content were synthesized by combining the solid-state reaction method,melting method and spark plasma sintering (SPS) method.The effects of Ga composition on high... N-type Si-based type-Ⅰ clathrates with different Ga content were synthesized by combining the solid-state reaction method,melting method and spark plasma sintering (SPS) method.The effects of Ga composition on high temperature thermoelectric transport properties were investigated.The results show that at room temperature,the carrier concentration decreases, while the carrier mobility increases slightly with increasing Ga content.The Seebeck coefficient increases with increasing Ga content. Among all the samples,Ba7.93Ga17.13Si28.72exhibits higher Seebeck coefficient than the others and reaches -135μV·K^-1 at 1000 K.The sample prepared by this method exhibits very high electrical conductivity,and reaches 1.95x 10^5 S·m^-1 for Ba8.01Ga16.61Si28.93 at room temperature.The thermal conductivity of all samples is almost temperature independent in the temperature range of 300-1000 K,indicating the behaviour of a typical metal.The maximum ZT value of 0.75 is obtained at 1000 K for the compound Ba7.93Ga17.13Si28.72. 展开更多
关键词 type-Ⅰ clathrate thermoelectric materials SYNTHESIS
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Influence of sintering temperature on the thermoelectric properties of Ba_8Ga_(16)Si_(30) clathrate treated by spark plasma sintering 被引量:1
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作者 Li-hua Liu Feng Li +3 位作者 Ning Chen Hong-mei Qiu Guo-hui Cao Yang Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2015年第1期78-85,共8页
A series of Ba8Ga16Si30 clathrate samples were prepared by arc melting, ball milling, acid washing, and spark plasma sintering (SPS). X-ray diffraction analysis revealed that the lattice of the Ba8Ga16Si30 samples e... A series of Ba8Ga16Si30 clathrate samples were prepared by arc melting, ball milling, acid washing, and spark plasma sintering (SPS). X-ray diffraction analysis revealed that the lattice of the Ba8Ga16Si30 samples expanded as the SPS temperature was increased from 400 to 750℃. Lattice contraction recurred when the SPS temperature was further increased in the range of 750-1000℃. This phenomenon can be explained by the variation of Ga content in the lattice. The thermoelectric figure of the merit ZT value of clathrates increased with the increase in SPS temperature and reached a maximum when the sample was subjected to SPS at 800℃. A further increase in SPS temperature did not contribute to the improvement of ZT. The variation of the lattice parameter a vs. SPS temperature T was similar to the variation ob-served in the ZT-T curve. 展开更多
关键词 clathrate compounds THERMOELECTRICITY sintering temperature spark plasma sintering lattice constants
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Effect of nanoparticles on the nucleation and agglomeration rates of hydrate growth using THF-water clathrates 被引量:1
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作者 Syed Y.Nahri James L.Nielsen Yuanhang Chen 《Petroleum Science》 SCIE CAS CSCD 2020年第2期467-476,共10页
Four types of nanoparticles,amorphous carbon,ironⅢoxide,SiO2,and amino-coated SiO2,were tested to determine changes in tetrahydrofuran-water(THF-water)clathrate hydrate nucleation and agglomeration.Rates were experim... Four types of nanoparticles,amorphous carbon,ironⅢoxide,SiO2,and amino-coated SiO2,were tested to determine changes in tetrahydrofuran-water(THF-water)clathrate hydrate nucleation and agglomeration.Rates were experimentally found to determine their viability for preventing natural gas hydrates from developing during offshore drilling operations.THF-water clathrates were chosen as a model to represent gas hydrate growth at atmospheric pressure.Concentrations of each nanoparticle between 0.15%and 1.0%by weight were tested as a kinetic inhibitor to hydrate formation.Tests were repeated at various temperatures below the formation temperature of 4.4℃for THF-water clathrate hydrates.Measurements were made to identify how the concentration of THF affects the clathrate hydrates forming under static conditions between20%and 30%by mole of THF.The primary tests in this study were performed using a 20:80 THF/water ratio.Temperature increases during hydrate nucleation for THF-water were measured between-5 and 3℃.The range of ideal nanoparticle concentrations was found to be between 0.15%and 0.45%by weight for optimal static,kinetic inhibition of hydrate nucleation.At approximately 0.3%by weight,the most significant inhibition was observed under static conditions for all four types of nanoparticles tested.We found that functionalized amino-coated SiO2 nanoparticles,across all tests,significantly increased the time required for the formation of THF-water clathrate hydrates compared to the other three non-functionalized nanoparticles.The amorphous carbon and ironⅢoxide nanoparticles performed similarly across each test and were both the least effective in their inhibition of the clathrate hydrates of the four nanoparticles studied compared to a control. 展开更多
关键词 NANOPARTICLES Gas HYDRATES clathrateS HYDRATE inhibition Functionalized NANOPARTICLES
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Lattice dynamics study of low energy guest-host coupling in clathrate hydrate 被引量:1
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作者 杨岳海 董顺乐 王琳 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第1期270-273,共4页
Our lattice dynamics simulation of Xe-hydrate with four-site TIP4P oxygen-shell model can accurately reproduce each peak position in the inelastic incoherent neutron scattering spectrum at the acoustic band (below 15... Our lattice dynamics simulation of Xe-hydrate with four-site TIP4P oxygen-shell model can accurately reproduce each peak position in the inelastic incoherent neutron scattering spectrum at the acoustic band (below 15 meV) and yield correct relative intensity. Based on the results, the uncertain profile at ~6 meV is assigned to anharmonic guest modes coupled strongly to small cages. Blue shift is proposed in phonon dispersion sheet in the case of anticrossing and found to be an evident signal for guest-host coupling that explains the anomalous thermal conductivity of clathrate hydrate. 展开更多
关键词 lattice dynamics clathrate hydrate guest-host coupling anticrossing
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Interaction Study of Guest with Host in Clathrate Hydrate
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作者 Shunle Dong 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2007年第4期423-427,共5页
Lattice dynamical simulations of noble gas hydrate structures I and II have been performed. Potential energies were investigated to study the influence of guest species on the stability of the hydrate structure. Resul... Lattice dynamical simulations of noble gas hydrate structures I and II have been performed. Potential energies were investigated to study the influence of guest species on the stability of the hydrate structure. Results show that when the diameter of inclusion molecules is between 3 A and 4.2 A, such as Ar and Kr, the critical role of the 512 cage in the stabilization of hydrates becomes effective. For Xe hydrates SI and SII, with the help of lattice dynamical calculations, the modes attributions are identified directly. We proposed the resonant effect of the fingerprint frequency at about 7 meV and 10 meV which arise from the coupling of Xe molecules in the 512 cage with the host lattice. 展开更多
关键词 clathrate hydrate He NE Ar KR XE lattice dynamical simulation
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A NOVEL SUPRAMOLECULAR CLATHRATE OF RODLIKE p-BUTOXYBENZYLIDENE-p′-DODECOXYANILINE TRAPPED WITHIN POLYORGANOSILOXANE PORE
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作者 许辉 曹新宇 +4 位作者 李泽 曹明 戴道荣 谢萍 张榕本 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1998年第3期253-260,共8页
A novel supramolecular polysiloxane clathrate, POS/C, has been preparedby in-situ encapsulating rodlike p-butoxybenzylidene-p ' - dodecoxyaniline (BBDA ) , one kindof Schiff base liquid crystal molecule, within th... A novel supramolecular polysiloxane clathrate, POS/C, has been preparedby in-situ encapsulating rodlike p-butoxybenzylidene-p ' - dodecoxyaniline (BBDA ) , one kindof Schiff base liquid crystal molecule, within the pore of polyorganosiloxane (POS) whichis prepared by hydrosilylation coupling reaction of polyvinylsilsesquioxane (Vi- T ) withtetramethyldisiloxane (H-MM). Investigation by polarized light microscopy (PLM), differ-ential scanning calorimetry (DSC), infrared spectroscopy (IR), atomic force microscopy(AFM) and molecular simulation gives a preliminary support to the existence of the titlesupramolecular clathrate. 展开更多
关键词 Supramolecular clathrate Polyorganosiloxane pore HYDROSILATION Encapsulation Characterization
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Structural, elastic, and electronic properties of sodium atoms encapsulated type-I silicon–clathrate compound under high pressure
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作者 张伟 陈青云 +1 位作者 曾召益 蔡灵仓 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第10期400-407,共8页
We calculated the structural, elastic, and electronic properties of alkali metal Na atoms doped type-I silicon-clathrate compound(Na8Si46) under pressure using first-principles methods. The obtained dependencies of ... We calculated the structural, elastic, and electronic properties of alkali metal Na atoms doped type-I silicon-clathrate compound(Na8Si46) under pressure using first-principles methods. The obtained dependencies of bond lengths and bond angles on pressure show heterogeneous behaviors which may bring out a structural transition. By using the elastic stability criteria from the calculated elastic constants, we confirm that the Na8Si46 is elastically unstable under high pressure. Some of the mechanical and thermal quantities include bulk modulus, shear modulus,Young's modulus, Debye temperature,sound velocity, melting point, and hardness, which are also derived from the elastic constants. The calculated total and partial electron densities of states of Na8Si46 indicate a weak interaction between the encapsulated Na atoms and the silicon framework. Moreover, the effect of pressure on its electronic structure is also investigated, which suggests that pressure is not a good choice to enhance the thermoelectricity performance of Na8Si46. 展开更多
关键词 clathrate compound elastic constants electronic structure density functional theory
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Sn-based type-VIII single-crystal clathrates with a large figure of merit
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作者 Deng Shu-Kang Li De-Cong +2 位作者 Shen Lan-Xian Hao Rui-Ting T.Takabatake 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第1期462-466,共5页
Single-crystal samples of type-VIII BasGa16-xCuxSn30 (x = 0, 0.03, 0.06, 0.15) clathrates were prepared using the Sn-flux method. At room temperature the carrier density, n, is 3.5-5 × 10^19 cm^-3 for all the s... Single-crystal samples of type-VIII BasGa16-xCuxSn30 (x = 0, 0.03, 0.06, 0.15) clathrates were prepared using the Sn-flux method. At room temperature the carrier density, n, is 3.5-5 × 10^19 cm^-3 for all the samples, the carrier mobility, μH, increases to more than twice that of BasGa16Sn30 for all the Cu doping samples, and consequently the electrical conductivity is enhanced distinctly from 1.90×10^4 S/m to 4.40 ×10^4 S/m, with the Cu composition increasing from x = 0 to x = 0.15. The Seebeck coefficient,α, decreases slightly with the increases in Cu composition. The values are about 0.72 W/mK at 300 K and are almost invariant with temperature up to 500 K for the samples with x = 0 and x = 0.03. The lattice thermal conductivity, μL, decreases from 0.59 W/InK for x = 0 to 0.50 W/mK for x = 0.03 at 300 K. The figure of merit for x = 0.03 reaches 1.35 at 540 K. 展开更多
关键词 thermoelectric material type-VIII clathrate thermoelectric properties
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Theoretical Studies on the Thermo- electric Properties of Tin-based Clathrates:Cs_8M_4Sn_(42)(M=Zn,Cd,Hg) and Cs_8Sn_(44)□_2
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作者 WANG Peng WU Li-Ming 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第12期1793-1804,共12页
The site occupancies and thermoelectric properties of tin-based clathrates Cs8M4Sn44□2 (M = Zn, Cd, Hg) and CssSn44□2 were studied by the first principle calculations. We had provided an efficient way to probe the... The site occupancies and thermoelectric properties of tin-based clathrates Cs8M4Sn44□2 (M = Zn, Cd, Hg) and CssSn44□2 were studied by the first principle calculations. We had provided an efficient way to probe the relationship between the crystalline structure and power factor. Detailed analyses indicated the p states of Sn at 16i and 24k sites together with the p states of M substitute contributed significantly to the maximum power factor, yet Cs atoms nearly did not. The dangling bonds of vacancies in Cs8Snn44□2 are also discussed. The power factors of p- and n-type CssMaSn42 and Cs8Sn44□2 at optimal temperature and carder concentration are predicted. Our results suggest that Cs8ZnaSn44□2 is a promising candidate at the 5.25 ×10^19 cm-3 hole carrier concentration as a high temperature thermoelectric material that is competitive to the state-of-art Ge-based clathrate thermoelectric materials. 展开更多
关键词 the first principle THERMOELECTRIC boltzmann theory clathrate tin electronic structure
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Electrical Transport Properties of Type-Ⅷ Sn-Based Single-Crystalline Clathrates (Eu/Ba)8Ga16Sn30 Prepared by Ga Flux Method
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作者 Shu-Ping Deng Feng Cheng +6 位作者 De-Cong Li Yu Tang Zhong Chen Lan-Xian Shen Hong-Xia Liu Pei-Zhi Yang Shu-Kang Deng 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第4期92-96,共5页
Single-crystalline samples of Eu/Ba-filled Sn-based type-Ⅷ clathrate are prepared by the Ga flux method with different stoichiometric ratios. The electrical transport properties of the samples are optimized by Eu dop... Single-crystalline samples of Eu/Ba-filled Sn-based type-Ⅷ clathrate are prepared by the Ga flux method with different stoichiometric ratios. The electrical transport properties of the samples are optimized by Eu doping. Results indicate that Eu atoms tend to replace Ba atoms. With the increase of the Eu initial content, the carrier density increases and the carrier mobility decreases, which leads to an increase of the Seebeck coefficient. By contrast, the electrical conductivity decreases. Finally, the sample with Eu initial content of x = 0.75 behaves with excellent electrical properties, which shows a maximal power factor of 1.51 mW·m^-1K^-2 at 480K, and the highest ZT achieved is 0.87 near the temperature of 483K. 展开更多
关键词 Seebeck Eu/Ba Electrical Transport Properties of Type Prepared by Ga Flux Method Sn-Based Single-Crystalline clathrates BA GA
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