Bulk skutterudite （FeNi）xCo4-xSbl2 with x varying from 0.05 to 1.0 were prepared by mechanical alloying and spark plasma sintering （MA-SPS）. The phases of the samples were analyzed by X-ray diffraction, and their ...Bulk skutterudite （FeNi）xCo4-xSbl2 with x varying from 0.05 to 1.0 were prepared by mechanical alloying and spark plasma sintering （MA-SPS）. The phases of the samples were analyzed by X-ray diffraction, and their thermoelectrical properties were tested by electrical constant instrument and laser thermal constant instrument. The experimental results show that bulk （FeNi）xCo4-xSb12 have the characteristic of typical semiconductor electricity. The addition of FeNi improves the electrical properties to a large extent; the samples of bulk （FeNi）xCo4-xSbl2 （x = 0.05-1.0） are n-type semiconducting materials; the increase of FeNi content can decrease the absolute value of Seebeck coefficient and therefore decrease the ZT value; FeNi with a higher content when x 〉 0.5 leads to an evident increase in thermal conductivity and also a decrease in ZT value. In general, for ZT value, the optimal added content of FeNi is 0.25-0.5 and the maximum ZT value is 0.2467 when x = 0.5 at 500℃.展开更多
The effects of Mg addition on mechanical thermo-electrical properties of Al.Mg/5%Al2O3 nanocomposite with differentMg contents （0, 5%, 10% and 20%） produced by mechanical alloying were studied. Scanning electron mic...The effects of Mg addition on mechanical thermo-electrical properties of Al.Mg/5%Al2O3 nanocomposite with differentMg contents （0, 5%, 10% and 20%） produced by mechanical alloying were studied. Scanning electron microscopy analysis （SEM）,X-ray diffraction analysis （XRD） and transmission electron microscopy （TEM） were used to characterize the produced powder. Theresults show that addition of Mg forms a predominant phase （Al.Mg solid solution）. By increasing the mass fraction of Mg, thecrystallite size decreases and the lattice strain increases which results from the atomic penetration of Mg atoms into the substitutionalsites of Al lattice. The microhardness of the composite increases with the increase of the Mg content. The thermal and electricalconductivities increase linearly with the temperature increase in the inspected temperature range. Moreover, the thermalconductivity increases with the increase of Mg content.展开更多
Engineering the electrical properties of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS)holds great potential for various applications such as sensors,thermoelectric(TE)generators,and hole transport...Engineering the electrical properties of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS)holds great potential for various applications such as sensors,thermoelectric(TE)generators,and hole transport layers in solar cells.Various strategies have been applied to achieve optimal electrical properties,including base solution post-treatments.However,the working mechanism and the exact details of the structural transformations induced by base post-treatments are still unclear.In this work,we present a comparative study on the post-treatment effects of using three common and green alkali base solutions:namely LiOH,NaOH,and KOH.The structural modifications induced in the film by the base post-treatments are studied by techniques including atomic force microscopy,grazing-incidence wide-angle X-ray scattering,ultraviolet–visible–near-infrared spectroscopy,and attenuated total reflectance Fourier-transform infrared spectroscopy.Base-induced structural modifications are responsible for an improvement in the TE power factor of the films,which depends on the basic solution used.The results are explained on the basis of the different affinity between the alkali cations and the PSS chains,which determines PEDOT dedoping.The results presented here shed light on the structural reorganization occurring in PEDOT:PSS when exposed to high-pH solutions and may serve as inspiration to create future pH-/ion-responsive devices for various applications.展开更多
Results? are presented on synthesis?? and crystal growth of? Gd2S3-Dy2S3 solid solution sulfides and study of their thermoelectric properties in the range of temperatures 80-400 K. Gd0.2Dy0.8S1.48 composition has the ...Results? are presented on synthesis?? and crystal growth of? Gd2S3-Dy2S3 solid solution sulfides and study of their thermoelectric properties in the range of temperatures 80-400 K. Gd0.2Dy0.8S1.48 composition has the best values of thermoelectric efficiency 0.39 x 10-3/K at 400 K.展开更多
Bulk SnSe is an excellent thermoelectrical material with the highest figure-of-merit value of ZT=2.&making it promising in applications.Temperature-dependent electrical and thermoelectrical properties of SnSe nano...Bulk SnSe is an excellent thermoelectrical material with the highest figure-of-merit value of ZT=2.&making it promising in applications.Temperature-dependent electrical and thermoelectrical properties of SnSe nanoplates are studied at low temperature.Conductivity drops and rises again as temperature is lowered.The Seebeck coefficient is positive at room temperature and becomes negative at low temperature.The change of the sign of the Seebeck coefficient indicates influence of bipolar transport of the semiconductive SnSe nanoplate.The bipolar transport is caused by the Fermi energy changing with temperature due to different contributions from donors and acceptors at different temperatures.展开更多
Theoretically,copper–niobium(Cu-Nb)composite superconducting cavities have excellent potential for high thermal and mechanical stability.They can appropriately exploit the high-gradient surface processing recipes dev...Theoretically,copper–niobium(Cu-Nb)composite superconducting cavities have excellent potential for high thermal and mechanical stability.They can appropriately exploit the high-gradient surface processing recipes developed for the bulk niobium(Nb)cavity and the thick copper(Cu)layer’s high thermal conductivity and rigidity,thereby enhancing the operational stability of the bulk Nb cavities.This study conducted a global review of the technical approaches employed for fabricating Cu-Nb composite superconducting cavities.We explored Cu-Nb composite superconducting cavities based on two technologies at the Institute of Modern Physics,Chinese Academy of Sciences(IMP,CAS),including their manufacturing processes,radio-frequency(RF)characteristics,and mechanical performance.These cavities exhibit robust mechanical stability.First,the investigation of several 1.3 GHz single-cell elliptical cavities using the Cu-Nb composite sheets indicated that the wavy structure at the Cu-Nb interface influenced the reliable welding of the Cu-Nb composite parts.We observed the generation and trapping of magnetic flux density during the T_c crossing of Nb in cooldown process.The cooling rates during the T_c crossing of Nb exerted a substantial impact on the performance of the cavities.Furthermore,we measured and analyzed the surface resistance R_(s)attributed to the trapped magnetic flux induced by the Seebeck effect after quenching events.Second,for the first time,a low-beta bulk Nb cavity was plated with Cu on its outer surface using electroplating technology.We achieved a high peak electric field E_(pk)of~88.8 MV/m at 2 K and the unloaded quality factor Q_(0)at the E_(pk)of 88.8 MV/m exceeded 1×10^(10).This demonstrated that the electroplating Cu on the bulk Nb cavity is a practical method of developing the Cu-Nb composite superconducting cavity with superior thermal stability.The results presented here provide valuable insights for applying Cu-Nb composite superconducting cavities in superconducting accelerators with stringent operational stability requirements.展开更多
Lead-free SnTe with naturally non-stoichiometric vacancies has a limited thermoelectric performance due to a deviated carrier concentration from the optimum.In this paper,we experimentally demonstrated that Gd with+3 ...Lead-free SnTe with naturally non-stoichiometric vacancies has a limited thermoelectric performance due to a deviated carrier concentration from the optimum.In this paper,we experimentally demonstrated that Gd with+3 valence state as a novel n-type dopant is an effective solution for reducing carrier concentration in SnTe.A lowest value of 7.6×10^(18) cm^(−3) has been achieved.Yet with the involvement of Gd doping,the slightly modified band structure requires a further Sndeficiency compensation to enhance the overall figure of merit zT.As a consequence,in the specific sample Sn_(0.91)Gd_(0.07)Te,we successfully achieved a low lattice thermal conductivity of 0.8 W/(m K)due to the high doping level and an improved zT approaching 0.8 at 850 K.展开更多
Wearable thermoelectric devices hold significant promise in the realm of self-powered wearable electron-ics,offering applications in energy harvesting,movement tracking,and health monitoring.Nevertheless,developing th...Wearable thermoelectric devices hold significant promise in the realm of self-powered wearable electron-ics,offering applications in energy harvesting,movement tracking,and health monitoring.Nevertheless,developing thermoelectric devices with exceptional flexibility,enduring thermoelectric stability,multi-functional sensing,and comfortable wear remains a challenge.In this work,a stretchable MXene-based thermoelectric fabric is designed to accurately discern temperature and strain stimuli.This is achieved by constructing an adhesive polydopamine(PDA)layer on the nylon fabric surface,which facilitates the subsequent MXene attachment through hydrogen bonding.This fusion results in MXene-based thermo-electric fabric that excels in both temperature sensing and strain sensing.The resultant MXene-based thermoelectric fabric exhibits outstanding temperature detection capability and cyclic stability,while also delivering excellent sensitivity,rapid responsiveness(60 ms),and remarkable durability in strain sens-ing(3200 cycles).Moreover,when affixed to a mask,this MXene-based thermoelectric fabric utilizes the temperature difference between the body and the environment to harness body heat,converting it into electrical energy and accurately discerning the body’s respiratory rate.In addition,the MXene-based ther-moelectric fabric can monitor the state of the body’s joint through its own deformation.Furthermore,it possesses the capability to convert solar energy into heat.These findings indicate that MXene-based ther-moelectric fabric holds great promise for applications in power generation,motion tracking,and health monitoring.展开更多
Thermoelectric water spitting to hydrogen systems has great potential in the production of environment-friendly fuel using renewable solar energy in the future.In this work,we prepared porous nanosheet Mo doping Ni_(5...Thermoelectric water spitting to hydrogen systems has great potential in the production of environment-friendly fuel using renewable solar energy in the future.In this work,we prepared porous nanosheet Mo doping Ni_(5)P_(4)catalysts on nickel foam with efficient hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)performance in alkaline media.Density Functional Theory(DFT)calculations and experimental studies have shown that Mo doping deadeneds the interaction between H and O atomic orbitals of transition state water molecules,effectively weakening the activation energy of H_(2)O dissociation.Therefore,Mo doping is favorable for enhancing HER activity with overpotential at 10 mA cm^(-2)of 93 mV and Tafel slope of 40.1 mV dec^(-1)in 1 M KOH.Besides,it exhibits high alkaline OER activity with an ultra-low overpotential of 200 mV at 10 mA cm^(-2).Moreover,this catalyst only needs 1.537 V in a dual-electrode configuration of the electrolytic cell,which is much lower than the commercial Pt/C-RuO_(2)couple(1.614 V).In addition,we have developed and constructed a solar thermoelectric generator(TEG)that is capable of floating on water.This TEG has a continuous power output and an exceptionally long lifespan,providing a stable power supply to the synthesized catalyst electrolyzer.It can produce a maximum power output of over 90 mW,meeting the requirement of converting solar radiation heat into usable electricity.As a result,the system achieves productivity of 0.11 mL min^(-1)H_(2).This solar thermal energy conversion technology shows the possibility of large-scale industrial production of H_(2)and provides a new idea for exploring heat source utilization.展开更多
The recent discovery of superconductivity above 90 K in the oxide Y-Ba-Cu-O has generated an intense research in this field. This report deals with the thermoelectric power (TEP) of a typical high T_c oxide supercondu...The recent discovery of superconductivity above 90 K in the oxide Y-Ba-Cu-O has generated an intense research in this field. This report deals with the thermoelectric power (TEP) of a typical high T_c oxide superconductor prepared at Peking University.展开更多
The accurate characterization of thermoelectric properties at low temperatures is crucial for the development of high-performance thermoelectric cooling devices. While measurement errors of thermoelectric properties a...The accurate characterization of thermoelectric properties at low temperatures is crucial for the development of high-performance thermoelectric cooling devices. While measurement errors of thermoelectric properties at temperatures above room temperature have been extensively discussed, there is a lack of standard measurement protocols and error analyses for low-temperature transport properties. In this study, we present a measurement system capable of characterizing all three key thermoelectric parameters, i.e., Seebeck coefficient, electrical conductivity, and thermal conductivity, for a single sample across a temperature range of 10 K to 300 K. We investigated six representative commercial Bi_(2)Te_(3)-based samples(three N-type and three P-type). Using an error propagation model, we systematically analyzed the measurement uncertainties of the three intrinsic parameters and the resulting thermoelectric figure of merit. Our findings reveal that measurement uncertainties for both N-type and P-type Bi_(2)Te_(3)-based materials can be effectively maintained below 5% in the temperature range of 40 K to 300 K. However, the uncertainties increase to over 10% at lower temperatures, primarily due to the relatively smaller values of electrical resistivity and Seebeck coefficients in this regime. This work establishes foundational data for Bi_(2)Te_(3)-based thermoelectric materials and provides a framework for broader investigations of advanced low-temperature thermoelectrics.展开更多
In the context of diminishing energy resources and worsening greenhouse effect,thermoelectric materials have great potential for sustainable development due to their green and environmentally friendly characteristics....In the context of diminishing energy resources and worsening greenhouse effect,thermoelectric materials have great potential for sustainable development due to their green and environmentally friendly characteristics.Among inorganic thermoelectric materials,copper sulfide compounds have greater potential than others due to their abundant element reserves on Earth,lower usage costs,non-toxicity,and good biocompatibility.Compared to organic thermoelectric materials,the"phonon liquid-electron crystal"(PLEC)feature of copper sulfide compounds makes them have stronger thermoelectric performance.This review summarizes the latest research progress in the synthesis methods and thermoelectric modification strategies of copper sulfide compounds.It first explains the importance of the solid-phase method in the manufacture of thermoelectric devices,and then focuses on the great potential of nanoscale synthesis technology based on liquid-phase method in the preparation of thermoelectric materials.Finally,it systematically discusses several strategies for regulating the thermoelectric performance of copper sulfide compounds,including adjusting the chemical proportion of Cu_(2-x)S and introducing element doping to regulate the crystal structure,phase composition,chemical composition,band structure,and nanoscale microstructure of copper sulfide compounds,and directly affecting ZT value by adjusting conductivity and thermal conductivity.In addition,it discusses composite engineering based on copper sulfide compounds,including inorganic,organic,and metal compounds,and discusses tri-component compounds derived from sulfide copper.Finally,it discusses the main challenges and prospects of the development of copper sulfide-based thermoelectric materials,hoping that this review will promote the development of copper sulfide-based thermoelectric materials.展开更多
Thermoelectric(TE)materials,with the ability to convert heat into electrical energy,can generate micro-electrical fields at electronic interfaces with biological systems,making them applicable in electric-catalyzing a...Thermoelectric(TE)materials,with the ability to convert heat into electrical energy,can generate micro-electrical fields at electronic interfaces with biological systems,making them applicable in electric-catalyzing as nanozymes,and modulate the infected microenvironment of skin wounds.Thereby,by harnessing temperature differences in vitro or in vivo,TE nanomaterials can provide antimicrobial reactive oxygen species(ROS)by catalyzing redox reactions,thereby accelerating wound healing by suppressing infection.However,despite their promising potential,there is still a lack of comprehensive understanding of the antimicrobial mechanisms,biocompatibility,and practical applications of TE nanomaterials in wound healing,as this is a newly-emerged sub-area of energy-related biomedical applications.This review aims to address this gap by highlighting the emerging progress of TE materials in wound healing,clarifying their mechanism and advances,emphasizing their potential challenges for commercialization and clinical use,and proposing novel design strategies of TE nanomaterials for effective antibacterial performance.展开更多
In two-dimensional bilayer systems,twist-angle-dependent electronic and thermoelectric properties have garnered significant scientific interest in recent years.In this work,based on a combination of density functional...In two-dimensional bilayer systems,twist-angle-dependent electronic and thermoelectric properties have garnered significant scientific interest in recent years.In this work,based on a combination of density functional theory and nonequilibrium Green’s function method,we explore the electronic and thermoelectric properties in blue-phosphorene nanoribbon-based heterojunction(BPNRHJ)with and without blue-phosphorene nanoribbon(BPNR)stack.Our calculations find that the electronic conductance and power factor can be strongly enhanced by the BPNR stack,and their enhancements can be further observed with the twist between the layers.The main reason for this is the electronic hybridization between the layers can provide new transport channels,and the twist can modulate the strength of interlayer electronic hybridization,resulting in extremely violent fluctuations in electron transmission and hence an enhanced power factor.While the phonon thermal conductance exhibits very low dependence on the layer stack and twist.Combining these factors,our results reveal that the thermoelectric performance can be greatly modulated and enhanced in twist bilayer BPNRHJ:the figure of merit will be over 2.5 in 4-4-ZBPNR@ZGNR-AA-8.8∘at 500 K.展开更多
Due to the weak interlayer interactions,the binary Ⅲ-Ⅵ chalcogenides Ga Se can exist in several distinct polymorphs.Among them,the so-called β-and ε-phases simultaneously exhibit favorable total energies and moder...Due to the weak interlayer interactions,the binary Ⅲ-Ⅵ chalcogenides Ga Se can exist in several distinct polymorphs.Among them,the so-called β-and ε-phases simultaneously exhibit favorable total energies and moderate band gaps,which offer a good platform to explore their thermoelectric properties.Here,we demonstrate by first-principles calculations that the two systems have very similar band structures and phonon dispersions,despite different stacking sequences between adjacent layers.Interestingly,the lattice thermal conductivity of ε-GaSe is obviously lower than that of β-GaSe,which is inherently tied to stronger lattice anharmonicity caused by bonding heterogeneity.Besides,both systems exhibit higher p-type power factors due to doubly degenerate bands with weaker dispersions around the valence band maximum.As a consequence,a significantly enhanced p-type figure-of-merit of 2.1 can be realized at 700 K along the out-of-plane direction of theε-phase.展开更多
Thermoelectric technology that utilizes thermodynamic effects to convert thermal energy into electrical energy has greatly expanded wearable health monitoring,personalized detecting,and communicating applications.Enco...Thermoelectric technology that utilizes thermodynamic effects to convert thermal energy into electrical energy has greatly expanded wearable health monitoring,personalized detecting,and communicating applications.Encouragingly,thermoelectric technology assisted by artificial intelligence exerts great development potential in wearable electronic devices that rely on the self-sustainable operation of human body heat.Ionic thermoelectric(i-TE)devices that possess high Seebeck coefficients and a constant and stable electrical output are expected to achieve an effective conversation of thermal energy harvesting.Herein,we developed an i-TE paster for thermal chargeable energy storage,temperature-triggered material recognition,contact/non-contact temperature detection,and photo thermoelectric conversion applications.An all-solid-state organic ionic gel electrolyte(PVDF-HFP-PEO gel)with onion epidermal cells-like structure was sandwiched between two electrodes,which take full advantage of a synergy between the Soret effect and the polymer thermal expansion effect,thus achieving the enhanced ZT value up to 900%compared with the PEO-free electrolyte.The i-TE device delivers a Seebeck coefficient of 28 mV K^(−1),a maximum energy conversion efficiency of 1.3%in performance,and ultra-thin and skin-attachable properties in wearability,which demonstrate the great potential and application prospect of the i-TE paster in self-sustainable wearable electronics.展开更多
Boundary engineering has proven effective in enhancing the thermoelectric performance of materials.SnSe,known for its low thermal conductivity,has garnered significant interest;however,its application is hindered by p...Boundary engineering has proven effective in enhancing the thermoelectric performance of materials.SnSe,known for its low thermal conductivity,has garnered significant interest;however,its application is hindered by poor electrical conductivity.Herein,the Ag_(8)GeSe_(6) is introduced into the p-type polycrystalline SnSe matrix to optimize the thermoelectric performance,and the in-situ Ag_(2)Se precipitates are formed in grain boundaries,which play dual roles,acting as an electron attraction center for improving hole concentration and a phonon scattering center for reducing lattice thermal conductivity.It effectively decouples the thermal and electrical transport properties to optimize the thermoelectric performance.Importantly,the amount of Ag_(2)Se can be controlled by adjusting the amount of Ag_(8)GeSe_(6) added to the SnSe matrix.The introduction of Ag_(8)GeSe_(6) enhances electrical conductivity due to the increased hole carrier caused by the introduced Ag+and the formed electron attraction center(in-situ Ag_(2)Se precipitates).Based on the DFT calculations,the band gap of the Ag_(8)GeSe_(6)-doped samples is considerably decreased,facilitating carrier transport.As a result,the electrical transport properties increase to 808μW m^(−1) K^(−2) at 823 K for SnSe+0.5 wt%Ag_(8)GeSe_(6).In addition,in-situ Ag_(2)Se precipitates in grain boundaries strongly enhance phonon scattering,causing a decrease in lattice thermal conductivity.Furthermore,the presence of defects contributes to a reduction in lattice thermal conductivity.Specifically,the thermal conductivity of SnSe+1.0 wt%Ag_(8)GeSe_(6) decreases to 0.29 W m^(−1) K^(−1) at 823 K.Consequently,SnSe+0.5 wt%Ag_(8)GeSe_(6) obtains a high ZT value of 1.7 at 823 K and maintains a high average ZT value of 0.57 over the temperature range of 323−773 K.Additionally,the mechanical properties of Ag_(8)GeSe_(6)-doped also show an improvement.These advancements can be applied to energy supply applications during deep space exploration.展开更多
We are delighted to introduce this Special Issue of Acta Metallurgica Sinica(English Letters)dedicated to"Thermoelectric Materials and Devices."Thermoelectric materials and devices have emerged as a promisin...We are delighted to introduce this Special Issue of Acta Metallurgica Sinica(English Letters)dedicated to"Thermoelectric Materials and Devices."Thermoelectric materials and devices have emerged as a promising technology for sustainable energy solutions,enabling efficient conversion between heat and electricity.This special collection highlights the latest advancements in the field,showcasing cutting-edge research and fostering interdisciplinary collaboration among researchers worldwide.展开更多
Famatinite(Cu_(3)SbS_(4),p-type)and chalcopyrite(CuFeS_(2),n-type)are well-recognized sustainable minerals with good intermediate-temperature thermoelectric performance.In this article,we utilize the inherent thermoel...Famatinite(Cu_(3)SbS_(4),p-type)and chalcopyrite(CuFeS_(2),n-type)are well-recognized sustainable minerals with good intermediate-temperature thermoelectric performance.In this article,we utilize the inherent thermoelectric properties of these compounds to demonstrate real-time operational performance as a coupled thermoelectric generator(TEG)for waste heat recovery applications.First,we synthesized the polycrystalline and nano-grained famatinite and chalcopyrite materials with high purity through a sustainable synthesis process of mechanical alloying followed by hot pressing.A maximum output power of~5 mW by the developed TEG was demonstrated while harvesting from a waste heat source of 723 K.Furthermore,the TEG performance via computational simulations for varied thermal gradients was validated.Our results highlight the sustainable development of thermoelectric power generator from earth-abundant minerals having strong stability and capacity to convert waste heat to electricity,which opens a new direction for fabricating a low-cost TEG for intermediate-temperature applications.展开更多
SnSe is a promising thermoelectric(TE) compound that has attracted increasing attention in recent years,highlighting its advantages in wide temperature range applications.Nanocomposite material engineering provides a ...SnSe is a promising thermoelectric(TE) compound that has attracted increasing attention in recent years,highlighting its advantages in wide temperature range applications.Nanocomposite material engineering provides a straightforward and practical approach to enhance the TE transport performance and mechanical strength of materials.In this study,SiC nanoparticles with varying mass percentages were incorporated into cubic SnSe-based TE materials using the wet ball milling method via mechanical activation(MA).During the rapid hotpressing sintering(HPS) process,the SiC nanoparticles dispersed at the matrix interface and effectively hindered grains growth owing to the pinning effect.The refined grains and multiple interfaces improved the hole carrier concentration(n) and enhanced the phonon scattering,which collectively optimized the electrical and thermal transport properties of cubic SnSe-based nanocomposites,thereby significantly improving the TE dimensionless figure of merit(ZT).Eventually,the sample with 1.25 wt%SiC achieved the highest ZT of ~1.14 at 750 K,which was twice that of the uncomposite sample.In terms of mechanical properties,the addition of SiC nanoparticles can effectively enhance the Vickers hardness(H_(v)) of the material,further demonstrating that this work offers an effective strategy for improving the performance of cubic SnSe-based TE materials.展开更多
文摘Bulk skutterudite （FeNi）xCo4-xSbl2 with x varying from 0.05 to 1.0 were prepared by mechanical alloying and spark plasma sintering （MA-SPS）. The phases of the samples were analyzed by X-ray diffraction, and their thermoelectrical properties were tested by electrical constant instrument and laser thermal constant instrument. The experimental results show that bulk （FeNi）xCo4-xSb12 have the characteristic of typical semiconductor electricity. The addition of FeNi improves the electrical properties to a large extent; the samples of bulk （FeNi）xCo4-xSbl2 （x = 0.05-1.0） are n-type semiconducting materials; the increase of FeNi content can decrease the absolute value of Seebeck coefficient and therefore decrease the ZT value; FeNi with a higher content when x 〉 0.5 leads to an evident increase in thermal conductivity and also a decrease in ZT value. In general, for ZT value, the optimal added content of FeNi is 0.25-0.5 and the maximum ZT value is 0.2467 when x = 0.5 at 500℃.
文摘The effects of Mg addition on mechanical thermo-electrical properties of Al.Mg/5%Al2O3 nanocomposite with differentMg contents （0, 5%, 10% and 20%） produced by mechanical alloying were studied. Scanning electron microscopy analysis （SEM）,X-ray diffraction analysis （XRD） and transmission electron microscopy （TEM） were used to characterize the produced powder. Theresults show that addition of Mg forms a predominant phase （Al.Mg solid solution）. By increasing the mass fraction of Mg, thecrystallite size decreases and the lattice strain increases which results from the atomic penetration of Mg atoms into the substitutionalsites of Al lattice. The microhardness of the composite increases with the increase of the Mg content. The thermal and electricalconductivities increase linearly with the temperature increase in the inspected temperature range. Moreover, the thermalconductivity increases with the increase of Mg content.
基金the Zernike Institute for Advanced Materials for the startup fundsChina Scholarship Council(201606340158)。
文摘Engineering the electrical properties of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS)holds great potential for various applications such as sensors,thermoelectric(TE)generators,and hole transport layers in solar cells.Various strategies have been applied to achieve optimal electrical properties,including base solution post-treatments.However,the working mechanism and the exact details of the structural transformations induced by base post-treatments are still unclear.In this work,we present a comparative study on the post-treatment effects of using three common and green alkali base solutions:namely LiOH,NaOH,and KOH.The structural modifications induced in the film by the base post-treatments are studied by techniques including atomic force microscopy,grazing-incidence wide-angle X-ray scattering,ultraviolet–visible–near-infrared spectroscopy,and attenuated total reflectance Fourier-transform infrared spectroscopy.Base-induced structural modifications are responsible for an improvement in the TE power factor of the films,which depends on the basic solution used.The results are explained on the basis of the different affinity between the alkali cations and the PSS chains,which determines PEDOT dedoping.The results presented here shed light on the structural reorganization occurring in PEDOT:PSS when exposed to high-pH solutions and may serve as inspiration to create future pH-/ion-responsive devices for various applications.
文摘Results? are presented on synthesis?? and crystal growth of? Gd2S3-Dy2S3 solid solution sulfides and study of their thermoelectric properties in the range of temperatures 80-400 K. Gd0.2Dy0.8S1.48 composition has the best values of thermoelectric efficiency 0.39 x 10-3/K at 400 K.
文摘Bulk SnSe is an excellent thermoelectrical material with the highest figure-of-merit value of ZT=2.&making it promising in applications.Temperature-dependent electrical and thermoelectrical properties of SnSe nanoplates are studied at low temperature.Conductivity drops and rises again as temperature is lowered.The Seebeck coefficient is positive at room temperature and becomes negative at low temperature.The change of the sign of the Seebeck coefficient indicates influence of bipolar transport of the semiconductive SnSe nanoplate.The bipolar transport is caused by the Fermi energy changing with temperature due to different contributions from donors and acceptors at different temperatures.
基金supported by the Large Research Infrastructures China initiative Accelerator Driven System(No.2017-000052-75-01-000590)the Youth Innovation Promotion Association of Chinese Academy of Sciences(No.2022422)+1 种基金the Young Scientists of National Natural Science Foundation of China(No.12005275)the Advanced Energy Science and Technology Guangdong Laboratory(No.HND22PTZZYY)。
文摘Theoretically,copper–niobium(Cu-Nb)composite superconducting cavities have excellent potential for high thermal and mechanical stability.They can appropriately exploit the high-gradient surface processing recipes developed for the bulk niobium(Nb)cavity and the thick copper(Cu)layer’s high thermal conductivity and rigidity,thereby enhancing the operational stability of the bulk Nb cavities.This study conducted a global review of the technical approaches employed for fabricating Cu-Nb composite superconducting cavities.We explored Cu-Nb composite superconducting cavities based on two technologies at the Institute of Modern Physics,Chinese Academy of Sciences(IMP,CAS),including their manufacturing processes,radio-frequency(RF)characteristics,and mechanical performance.These cavities exhibit robust mechanical stability.First,the investigation of several 1.3 GHz single-cell elliptical cavities using the Cu-Nb composite sheets indicated that the wavy structure at the Cu-Nb interface influenced the reliable welding of the Cu-Nb composite parts.We observed the generation and trapping of magnetic flux density during the T_c crossing of Nb in cooldown process.The cooling rates during the T_c crossing of Nb exerted a substantial impact on the performance of the cavities.Furthermore,we measured and analyzed the surface resistance R_(s)attributed to the trapped magnetic flux induced by the Seebeck effect after quenching events.Second,for the first time,a low-beta bulk Nb cavity was plated with Cu on its outer surface using electroplating technology.We achieved a high peak electric field E_(pk)of~88.8 MV/m at 2 K and the unloaded quality factor Q_(0)at the E_(pk)of 88.8 MV/m exceeded 1×10^(10).This demonstrated that the electroplating Cu on the bulk Nb cavity is a practical method of developing the Cu-Nb composite superconducting cavity with superior thermal stability.The results presented here provide valuable insights for applying Cu-Nb composite superconducting cavities in superconducting accelerators with stringent operational stability requirements.
基金sponsored by the National Natural Science Foundation of China(52371193,52001231,and 52272006)the Shanghai Academic Research Leader(23XD1421200)+2 种基金the Shanghai Rising-Star Program(23QA1403900)the Chenguang Program supported by Shanghai Education Development Foundation&Shanghai Municipal Education Commission,the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions(TP2022122)the Shanghai Oriental Talented Youth Project,Space Application System of China Manned Space Program(KJZ-YY-NCL-0405).
文摘Lead-free SnTe with naturally non-stoichiometric vacancies has a limited thermoelectric performance due to a deviated carrier concentration from the optimum.In this paper,we experimentally demonstrated that Gd with+3 valence state as a novel n-type dopant is an effective solution for reducing carrier concentration in SnTe.A lowest value of 7.6×10^(18) cm^(−3) has been achieved.Yet with the involvement of Gd doping,the slightly modified band structure requires a further Sndeficiency compensation to enhance the overall figure of merit zT.As a consequence,in the specific sample Sn_(0.91)Gd_(0.07)Te,we successfully achieved a low lattice thermal conductivity of 0.8 W/(m K)due to the high doping level and an improved zT approaching 0.8 at 850 K.
基金supported by the National Natural Science Foundation of China(No.21975107)the China Scholarship Council(No.202206790046).
文摘Wearable thermoelectric devices hold significant promise in the realm of self-powered wearable electron-ics,offering applications in energy harvesting,movement tracking,and health monitoring.Nevertheless,developing thermoelectric devices with exceptional flexibility,enduring thermoelectric stability,multi-functional sensing,and comfortable wear remains a challenge.In this work,a stretchable MXene-based thermoelectric fabric is designed to accurately discern temperature and strain stimuli.This is achieved by constructing an adhesive polydopamine(PDA)layer on the nylon fabric surface,which facilitates the subsequent MXene attachment through hydrogen bonding.This fusion results in MXene-based thermo-electric fabric that excels in both temperature sensing and strain sensing.The resultant MXene-based thermoelectric fabric exhibits outstanding temperature detection capability and cyclic stability,while also delivering excellent sensitivity,rapid responsiveness(60 ms),and remarkable durability in strain sens-ing(3200 cycles).Moreover,when affixed to a mask,this MXene-based thermoelectric fabric utilizes the temperature difference between the body and the environment to harness body heat,converting it into electrical energy and accurately discerning the body’s respiratory rate.In addition,the MXene-based ther-moelectric fabric can monitor the state of the body’s joint through its own deformation.Furthermore,it possesses the capability to convert solar energy into heat.These findings indicate that MXene-based ther-moelectric fabric holds great promise for applications in power generation,motion tracking,and health monitoring.
基金supported by the Hainan Provincial Natural Science Foundation of China(Nos.522MS038 and 522QN282)the National Natural Science Foundation of China(Nos.52172086 and 52301268)the Start-up Research Foundation of Hainan University(No.KYQD(ZR)-22019).
文摘Thermoelectric water spitting to hydrogen systems has great potential in the production of environment-friendly fuel using renewable solar energy in the future.In this work,we prepared porous nanosheet Mo doping Ni_(5)P_(4)catalysts on nickel foam with efficient hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)performance in alkaline media.Density Functional Theory(DFT)calculations and experimental studies have shown that Mo doping deadeneds the interaction between H and O atomic orbitals of transition state water molecules,effectively weakening the activation energy of H_(2)O dissociation.Therefore,Mo doping is favorable for enhancing HER activity with overpotential at 10 mA cm^(-2)of 93 mV and Tafel slope of 40.1 mV dec^(-1)in 1 M KOH.Besides,it exhibits high alkaline OER activity with an ultra-low overpotential of 200 mV at 10 mA cm^(-2).Moreover,this catalyst only needs 1.537 V in a dual-electrode configuration of the electrolytic cell,which is much lower than the commercial Pt/C-RuO_(2)couple(1.614 V).In addition,we have developed and constructed a solar thermoelectric generator(TEG)that is capable of floating on water.This TEG has a continuous power output and an exceptionally long lifespan,providing a stable power supply to the synthesized catalyst electrolyzer.It can produce a maximum power output of over 90 mW,meeting the requirement of converting solar radiation heat into usable electricity.As a result,the system achieves productivity of 0.11 mL min^(-1)H_(2).This solar thermal energy conversion technology shows the possibility of large-scale industrial production of H_(2)and provides a new idea for exploring heat source utilization.
基金Project supported by the National Natural Science Foundation of China
文摘The recent discovery of superconductivity above 90 K in the oxide Y-Ba-Cu-O has generated an intense research in this field. This report deals with the thermoelectric power (TEP) of a typical high T_c oxide superconductor prepared at Peking University.
基金supported by the National Natural Science Foundation of China (Grant No. 52172259)the National Key Research and Development Program of China (Grant Nos. 2021YFA0718700 and 2022YFB3803900)the Fundamental Research Funds for the Inner Mongolia Normal University (Grant No. 2022JBTD008)。
文摘The accurate characterization of thermoelectric properties at low temperatures is crucial for the development of high-performance thermoelectric cooling devices. While measurement errors of thermoelectric properties at temperatures above room temperature have been extensively discussed, there is a lack of standard measurement protocols and error analyses for low-temperature transport properties. In this study, we present a measurement system capable of characterizing all three key thermoelectric parameters, i.e., Seebeck coefficient, electrical conductivity, and thermal conductivity, for a single sample across a temperature range of 10 K to 300 K. We investigated six representative commercial Bi_(2)Te_(3)-based samples(three N-type and three P-type). Using an error propagation model, we systematically analyzed the measurement uncertainties of the three intrinsic parameters and the resulting thermoelectric figure of merit. Our findings reveal that measurement uncertainties for both N-type and P-type Bi_(2)Te_(3)-based materials can be effectively maintained below 5% in the temperature range of 40 K to 300 K. However, the uncertainties increase to over 10% at lower temperatures, primarily due to the relatively smaller values of electrical resistivity and Seebeck coefficients in this regime. This work establishes foundational data for Bi_(2)Te_(3)-based thermoelectric materials and provides a framework for broader investigations of advanced low-temperature thermoelectrics.
文摘In the context of diminishing energy resources and worsening greenhouse effect,thermoelectric materials have great potential for sustainable development due to their green and environmentally friendly characteristics.Among inorganic thermoelectric materials,copper sulfide compounds have greater potential than others due to their abundant element reserves on Earth,lower usage costs,non-toxicity,and good biocompatibility.Compared to organic thermoelectric materials,the"phonon liquid-electron crystal"(PLEC)feature of copper sulfide compounds makes them have stronger thermoelectric performance.This review summarizes the latest research progress in the synthesis methods and thermoelectric modification strategies of copper sulfide compounds.It first explains the importance of the solid-phase method in the manufacture of thermoelectric devices,and then focuses on the great potential of nanoscale synthesis technology based on liquid-phase method in the preparation of thermoelectric materials.Finally,it systematically discusses several strategies for regulating the thermoelectric performance of copper sulfide compounds,including adjusting the chemical proportion of Cu_(2-x)S and introducing element doping to regulate the crystal structure,phase composition,chemical composition,band structure,and nanoscale microstructure of copper sulfide compounds,and directly affecting ZT value by adjusting conductivity and thermal conductivity.In addition,it discusses composite engineering based on copper sulfide compounds,including inorganic,organic,and metal compounds,and discusses tri-component compounds derived from sulfide copper.Finally,it discusses the main challenges and prospects of the development of copper sulfide-based thermoelectric materials,hoping that this review will promote the development of copper sulfide-based thermoelectric materials.
基金financially supported by the Sichuan Science and Technology Program(Nos.2023ZYD0064 and 2023YFG0220)the Fundamental Research Funds for the Central Universities(No.YJ202242)the Research Funding from West China School/Hospital of Stomatology,Sichuan University(No.QDJF2022–2).
文摘Thermoelectric(TE)materials,with the ability to convert heat into electrical energy,can generate micro-electrical fields at electronic interfaces with biological systems,making them applicable in electric-catalyzing as nanozymes,and modulate the infected microenvironment of skin wounds.Thereby,by harnessing temperature differences in vitro or in vivo,TE nanomaterials can provide antimicrobial reactive oxygen species(ROS)by catalyzing redox reactions,thereby accelerating wound healing by suppressing infection.However,despite their promising potential,there is still a lack of comprehensive understanding of the antimicrobial mechanisms,biocompatibility,and practical applications of TE nanomaterials in wound healing,as this is a newly-emerged sub-area of energy-related biomedical applications.This review aims to address this gap by highlighting the emerging progress of TE materials in wound healing,clarifying their mechanism and advances,emphasizing their potential challenges for commercialization and clinical use,and proposing novel design strategies of TE nanomaterials for effective antibacterial performance.
基金supported by the Key Projects of Department of Education of Hunan Province,China(Grant No.21A0167)the Natural Science Foundation of Hunan Province,China(Grant No.2019JJ40532)the Talent Introducing Foundation of Central South University of Forestry and Technology(Grant No.104-0160)。
文摘In two-dimensional bilayer systems,twist-angle-dependent electronic and thermoelectric properties have garnered significant scientific interest in recent years.In this work,based on a combination of density functional theory and nonequilibrium Green’s function method,we explore the electronic and thermoelectric properties in blue-phosphorene nanoribbon-based heterojunction(BPNRHJ)with and without blue-phosphorene nanoribbon(BPNR)stack.Our calculations find that the electronic conductance and power factor can be strongly enhanced by the BPNR stack,and their enhancements can be further observed with the twist between the layers.The main reason for this is the electronic hybridization between the layers can provide new transport channels,and the twist can modulate the strength of interlayer electronic hybridization,resulting in extremely violent fluctuations in electron transmission and hence an enhanced power factor.While the phonon thermal conductance exhibits very low dependence on the layer stack and twist.Combining these factors,our results reveal that the thermoelectric performance can be greatly modulated and enhanced in twist bilayer BPNRHJ:the figure of merit will be over 2.5 in 4-4-ZBPNR@ZGNR-AA-8.8∘at 500 K.
基金supported by the National Natural Science Foundation of China(Grant Nos.62074114 and 12474019)。
文摘Due to the weak interlayer interactions,the binary Ⅲ-Ⅵ chalcogenides Ga Se can exist in several distinct polymorphs.Among them,the so-called β-and ε-phases simultaneously exhibit favorable total energies and moderate band gaps,which offer a good platform to explore their thermoelectric properties.Here,we demonstrate by first-principles calculations that the two systems have very similar band structures and phonon dispersions,despite different stacking sequences between adjacent layers.Interestingly,the lattice thermal conductivity of ε-GaSe is obviously lower than that of β-GaSe,which is inherently tied to stronger lattice anharmonicity caused by bonding heterogeneity.Besides,both systems exhibit higher p-type power factors due to doubly degenerate bands with weaker dispersions around the valence band maximum.As a consequence,a significantly enhanced p-type figure-of-merit of 2.1 can be realized at 700 K along the out-of-plane direction of theε-phase.
基金supported by National Natural Science Foundation of China(62474019)Beijing Natural Science Foundation(L223006)BIT Research and Innovation Promoting Project(2024YCXY001).
文摘Thermoelectric technology that utilizes thermodynamic effects to convert thermal energy into electrical energy has greatly expanded wearable health monitoring,personalized detecting,and communicating applications.Encouragingly,thermoelectric technology assisted by artificial intelligence exerts great development potential in wearable electronic devices that rely on the self-sustainable operation of human body heat.Ionic thermoelectric(i-TE)devices that possess high Seebeck coefficients and a constant and stable electrical output are expected to achieve an effective conversation of thermal energy harvesting.Herein,we developed an i-TE paster for thermal chargeable energy storage,temperature-triggered material recognition,contact/non-contact temperature detection,and photo thermoelectric conversion applications.An all-solid-state organic ionic gel electrolyte(PVDF-HFP-PEO gel)with onion epidermal cells-like structure was sandwiched between two electrodes,which take full advantage of a synergy between the Soret effect and the polymer thermal expansion effect,thus achieving the enhanced ZT value up to 900%compared with the PEO-free electrolyte.The i-TE device delivers a Seebeck coefficient of 28 mV K^(−1),a maximum energy conversion efficiency of 1.3%in performance,and ultra-thin and skin-attachable properties in wearability,which demonstrate the great potential and application prospect of the i-TE paster in self-sustainable wearable electronics.
基金supported by the Outstanding Youth Fund of Yunnan Province(Grant No.202201AV070005)the National Natural Science Foundation of China(Grant No.52162029)the National Key R&D Program of China(Grant No.2022YFF0503804).
文摘Boundary engineering has proven effective in enhancing the thermoelectric performance of materials.SnSe,known for its low thermal conductivity,has garnered significant interest;however,its application is hindered by poor electrical conductivity.Herein,the Ag_(8)GeSe_(6) is introduced into the p-type polycrystalline SnSe matrix to optimize the thermoelectric performance,and the in-situ Ag_(2)Se precipitates are formed in grain boundaries,which play dual roles,acting as an electron attraction center for improving hole concentration and a phonon scattering center for reducing lattice thermal conductivity.It effectively decouples the thermal and electrical transport properties to optimize the thermoelectric performance.Importantly,the amount of Ag_(2)Se can be controlled by adjusting the amount of Ag_(8)GeSe_(6) added to the SnSe matrix.The introduction of Ag_(8)GeSe_(6) enhances electrical conductivity due to the increased hole carrier caused by the introduced Ag+and the formed electron attraction center(in-situ Ag_(2)Se precipitates).Based on the DFT calculations,the band gap of the Ag_(8)GeSe_(6)-doped samples is considerably decreased,facilitating carrier transport.As a result,the electrical transport properties increase to 808μW m^(−1) K^(−2) at 823 K for SnSe+0.5 wt%Ag_(8)GeSe_(6).In addition,in-situ Ag_(2)Se precipitates in grain boundaries strongly enhance phonon scattering,causing a decrease in lattice thermal conductivity.Furthermore,the presence of defects contributes to a reduction in lattice thermal conductivity.Specifically,the thermal conductivity of SnSe+1.0 wt%Ag_(8)GeSe_(6) decreases to 0.29 W m^(−1) K^(−1) at 823 K.Consequently,SnSe+0.5 wt%Ag_(8)GeSe_(6) obtains a high ZT value of 1.7 at 823 K and maintains a high average ZT value of 0.57 over the temperature range of 323−773 K.Additionally,the mechanical properties of Ag_(8)GeSe_(6)-doped also show an improvement.These advancements can be applied to energy supply applications during deep space exploration.
文摘We are delighted to introduce this Special Issue of Acta Metallurgica Sinica(English Letters)dedicated to"Thermoelectric Materials and Devices."Thermoelectric materials and devices have emerged as a promising technology for sustainable energy solutions,enabling efficient conversion between heat and electricity.This special collection highlights the latest advancements in the field,showcasing cutting-edge research and fostering interdisciplinary collaboration among researchers worldwide.
基金supported by the Research Grants Council of Hong Kong Special Administrative Region under the Faculty Development Scheme Project no:UGC/FDS16/E01/23.
文摘Famatinite(Cu_(3)SbS_(4),p-type)and chalcopyrite(CuFeS_(2),n-type)are well-recognized sustainable minerals with good intermediate-temperature thermoelectric performance.In this article,we utilize the inherent thermoelectric properties of these compounds to demonstrate real-time operational performance as a coupled thermoelectric generator(TEG)for waste heat recovery applications.First,we synthesized the polycrystalline and nano-grained famatinite and chalcopyrite materials with high purity through a sustainable synthesis process of mechanical alloying followed by hot pressing.A maximum output power of~5 mW by the developed TEG was demonstrated while harvesting from a waste heat source of 723 K.Furthermore,the TEG performance via computational simulations for varied thermal gradients was validated.Our results highlight the sustainable development of thermoelectric power generator from earth-abundant minerals having strong stability and capacity to convert waste heat to electricity,which opens a new direction for fabricating a low-cost TEG for intermediate-temperature applications.
基金financially supported by Taishan Scholar Program of Shandong Province(No.tsqn202306225)Shandong Postdoctoral Science Foundation(SDBX2023025)+2 种基金the leader of scientific research studio program of Jinan(grant no.2021GXRC082)the University of Jinan Disciplinary Cross-Convergence Construction Projects 2023(Nos.XKJC-202301 and XKJC-202311)Jinan City-School Integration Development Strategy Project(No.JNSX2023015 and No.JNSX2023018)
文摘SnSe is a promising thermoelectric(TE) compound that has attracted increasing attention in recent years,highlighting its advantages in wide temperature range applications.Nanocomposite material engineering provides a straightforward and practical approach to enhance the TE transport performance and mechanical strength of materials.In this study,SiC nanoparticles with varying mass percentages were incorporated into cubic SnSe-based TE materials using the wet ball milling method via mechanical activation(MA).During the rapid hotpressing sintering(HPS) process,the SiC nanoparticles dispersed at the matrix interface and effectively hindered grains growth owing to the pinning effect.The refined grains and multiple interfaces improved the hole carrier concentration(n) and enhanced the phonon scattering,which collectively optimized the electrical and thermal transport properties of cubic SnSe-based nanocomposites,thereby significantly improving the TE dimensionless figure of merit(ZT).Eventually,the sample with 1.25 wt%SiC achieved the highest ZT of ~1.14 at 750 K,which was twice that of the uncomposite sample.In terms of mechanical properties,the addition of SiC nanoparticles can effectively enhance the Vickers hardness(H_(v)) of the material,further demonstrating that this work offers an effective strategy for improving the performance of cubic SnSe-based TE materials.
