Electrostatic energy storage technology based on dielectrics is the basis of advanced electronics and high-power electrical systems.High polarization(P)and high electric breakdown strength(Eb)are the key parameters fo...Electrostatic energy storage technology based on dielectrics is the basis of advanced electronics and high-power electrical systems.High polarization(P)and high electric breakdown strength(Eb)are the key parameters for dielectric materials to achieve superior energy storage performance.In this work,a composite strategy based on antiferroelectric dielectrics(AFEs)has been proposed to improve the energy storage performance.Here,AlN is selected as the second phase for the(Pb_(0.915)Ba_(0.04)La_(0.03))(Zr_(0.65)Sn_(0.3)Ti_(0.05))O_(3)(PBLZST)AFEs,which is embedded in the grain boundaries to construct insulating networks and regulate the local electric field,improving the Eb.Meanwhile,it is emphasized that AFEs have the AFE–FE and FE–AFE phase transitions,and the increase of the phase transition electric fields can further improve the recoverable energy density(Wrec).As a result,the Eb increases from 180 to 290 kV·cm−1 with a simultaneous increase of the phase transition electric fields,magnifying the Wrec to~144%of the pristine PBLZST.The mechanism for enhanced Eb and the phase transition electric fields is revealed by the finite element simulation method.Moreover,the PBLZST:1.0 wt%AlN composite ceramics exhibit favorable temperature stability,frequency stability,and charge–discharge ability,making the composite ceramics a promising candidate for energy storage applications.展开更多
Carbon neutrality calls for renewable energies,and the efficient use of renewable energies requires energy storage mediums that enable the storage of excess energy and reuse after spatiotemporal reallocation.Compared ...Carbon neutrality calls for renewable energies,and the efficient use of renewable energies requires energy storage mediums that enable the storage of excess energy and reuse after spatiotemporal reallocation.Compared with traditional energy storage technologies,mobile energy storage technologies have the merits of low cost and high energy conversion efficiency,can be flexibly located,and cover a largerange from miniature to large systems and from high energy density to high power density,although most of them still face challenges or technical bottlenecks.In this review,we provide an overview of the opportunities and challenges of these emerging energy storagetechnologies(induding rechargeable batteries,fuel cells,and electrochemical and dielectric capacitors).Innovative materials,strategies,and technologies are highlighted.Finally,the future directions are envisioned.We hope this review will advance the development of mobile energy storage technologies and boost carbon neutrality.展开更多
Integrated sensor combines multiple sensor functions into a single unit,which has the advantages of miniaturization and better application potential.However,limited by the sensing platforms of the sensor and the selec...Integrated sensor combines multiple sensor functions into a single unit,which has the advantages of miniaturization and better application potential.However,limited by the sensing platforms of the sensor and the selectivity of the sensitive film,there are still challenges to realize multi-component gas detection in one unit.Herein,a principle integration method is proposed to achieve the multi-component gas detection based on the acoustics-electricity-mechanics coupling effect.The electrical and mechanical properties of the Bi_(2)S_(3)nanobelts materials in different atmospheres indicate the possibility of realizing the principle integration.At the same time,the surface acoustic wave(SAW)sensor as a multivariable physical transducer can sense both electrical and mechanical properties.Upon exposure to 10 ppm NO_(2),NH_(3),and their mixtures,the integrated SAW gas sensor shows a 4.5 kHz positive frequency shift(acoustoelectric effect),an 11 kHz negative frequency shift(mechanics effects),and a reduced 4 kHz negative frequency shift(acoustics-electricity-mechanics coupling effect),respectively.Moreover,we realize wireless passive detection of NO_(2)and NH_(3)based on the SAW sensor.Our work provides valuable insights that can serve as a guide to the design and fabrication of single sensors offering multi-component gas detection via different gas sensing mechanisms.展开更多
The scale-free ferroelectric polarization of fluorite MO_(2)(M=Hf,Zr)due to flat polar phonon bands are promising for nonvolatile memories.Defects are also widely introduced to improve the emergent ferroelectricity.Ho...The scale-free ferroelectric polarization of fluorite MO_(2)(M=Hf,Zr)due to flat polar phonon bands are promising for nonvolatile memories.Defects are also widely introduced to improve the emergent ferroelectricity.However,their roles are still not fully understood at the atomic-level.Here,we report a significant effect of point-defect-driven flattening of polar phonon bands with more polar modes and polarization contribution in doped MO_(2).The polar phonon bands in La-doped MO_(2)(M=Hf,Zr)can be significantly flattened,compared with pure ones.However,the lower energy barrier with larger polarization of VO-only doped MO_(2) compared with La-doped cases suggest that VO and local lattice distortion should be balanced for high-performance fluorite ferroelectricity.The work is believed to bridge the relation between point defects and the generally enhanced induced ferroelectricity in fluorite ferroelectrics at the atomic-level and inspire their further property optimization via defect-engineering.展开更多
Electrocaloric effect(ECE)is promising in realizing solid-state cooling as an alternative to the conventional refrigeration with environmentally harmful coolant and low efficiency.High ECE in lead-free ferroelectric c...Electrocaloric effect(ECE)is promising in realizing solid-state cooling as an alternative to the conventional refrigeration with environmentally harmful coolant and low efficiency.High ECE in lead-free ferroelectric ceramics is highly desirable for the EC cooling.In this work,different from the researches that tune the ECE by conventional compositional design or external stress engineering,we fabricated the(1-x)BaTiO_(3)-xNaNbO_(3)(BTO-xNN)lead-free ceramics with a core-shell grain structure arising from the inhomogeneous stoichiometry of element distribution,leading to the internal compressing stress in the grains.It is interesting that the phase transition behavior,including the phase transition temperature and the diffusion property,is regulated by the core-shell grain structure induced internal stress,which can be capitalized on for the favorable ECE.Cooperated with 0.02 NN,a high ECE,e.g.adiabatic temperature change(ΔT)of 3.6 K and isothermal entropy change(ΔS)of 4.5 J kg^(-1) K^(-1),is attained in the BTO ceramic.As the internal stress further increases with more NN,the BTO-0.06NN exhibits an extremely stable ECE with a variety rate below ±4% in a wide temperature range from 300 K to 360 K.This work provides a novel approach to explore pronounced ECE in lead-free ferroelectrics for eco-friendly refrigeration.展开更多
Solid-state cooling technology based on electrocaloric effect(ECE)has been advanced as an alternative to replace the vapour-compression approach to overcome the releasing of the global warming gases.However,the develo...Solid-state cooling technology based on electrocaloric effect(ECE)has been advanced as an alternative to replace the vapour-compression approach to overcome the releasing of the global warming gases.However,the development in high ECE materials is still a challenge.In this work,polarization merging strategy was proposed to achieve a large ECE in xBa(Sn_(0.07)Ti_(0.93))O_(3)–(1−x)Ba(Hf_(0.1)Ti_(0.9))O_(3) ferroelectric ceramics,where x=0,0.2,0.4,0.6,0.8,and 1.Ba(Sn_(0.07)Ti_(0.93))O_(3) with an orthorhombic phase and Ba(Hf_(0.1)Ti_(0.9))O_(3) with a rhombohedral phase at room temperature were prepared beforehand as precursors,and phase-coexisted xBSnT–(1−x)BHfT ceramics were formed via a solid-state reaction approach.Phase coexisting structures were confirmed using the X-ray diffraction.The merged polarization was confirmed by the dielectric and ferroelectric properties.Optimal ECEs were obtained for 0.2BSnT–0.8BHfT ceramics,i.e.,adiabatic temperature change DT=2.16±0.08 K at 80℃and 5 MV/m,and DT=3.35±0.09 K at 80℃and 7 MV/m.展开更多
基金supported by the National Natural Science Foundation of China(51972126,51972125,and 52172114)the Key Research and Development Project of Hubei Province(2020BAB067)+2 种基金HUST International Cooperation and Exchange Project,Double First Class Program of China(5001182055)the Innovation Research Fund of Huazhong University of Science and Technology(2019KFYRCPY126 and 2018KFYYXJJ052)the Innovation Fund of WNLO.We also would like to acknowledge the Analytical and Testing Center of Huazhong University of Science and Technology.
文摘Electrostatic energy storage technology based on dielectrics is the basis of advanced electronics and high-power electrical systems.High polarization(P)and high electric breakdown strength(Eb)are the key parameters for dielectric materials to achieve superior energy storage performance.In this work,a composite strategy based on antiferroelectric dielectrics(AFEs)has been proposed to improve the energy storage performance.Here,AlN is selected as the second phase for the(Pb_(0.915)Ba_(0.04)La_(0.03))(Zr_(0.65)Sn_(0.3)Ti_(0.05))O_(3)(PBLZST)AFEs,which is embedded in the grain boundaries to construct insulating networks and regulate the local electric field,improving the Eb.Meanwhile,it is emphasized that AFEs have the AFE–FE and FE–AFE phase transitions,and the increase of the phase transition electric fields can further improve the recoverable energy density(Wrec).As a result,the Eb increases from 180 to 290 kV·cm−1 with a simultaneous increase of the phase transition electric fields,magnifying the Wrec to~144%of the pristine PBLZST.The mechanism for enhanced Eb and the phase transition electric fields is revealed by the finite element simulation method.Moreover,the PBLZST:1.0 wt%AlN composite ceramics exhibit favorable temperature stability,frequency stability,and charge–discharge ability,making the composite ceramics a promising candidate for energy storage applications.
基金National Na tural Science Foundation of China(grants 52173163,51972126,52172114,and 22122202)National 1000-Talents Program,the Innovation Fund of WNLO,Wenzhou Science and Technology Bureau(grant ZG2022020)Huazhong University of Science and Technology(grant 2023BR021).
文摘Carbon neutrality calls for renewable energies,and the efficient use of renewable energies requires energy storage mediums that enable the storage of excess energy and reuse after spatiotemporal reallocation.Compared with traditional energy storage technologies,mobile energy storage technologies have the merits of low cost and high energy conversion efficiency,can be flexibly located,and cover a largerange from miniature to large systems and from high energy density to high power density,although most of them still face challenges or technical bottlenecks.In this review,we provide an overview of the opportunities and challenges of these emerging energy storagetechnologies(induding rechargeable batteries,fuel cells,and electrochemical and dielectric capacitors).Innovative materials,strategies,and technologies are highlighted.Finally,the future directions are envisioned.We hope this review will advance the development of mobile energy storage technologies and boost carbon neutrality.
基金supported by the National Natural Science Foundation of China(No.61922032)We thank the Program for the Academic Frontier Youth Team of Huazhong University of Science and Technology(HUST)(No.2018QYTD06)the Innovation Fund of Wuhan National Laboratory for Optoelectronics.
文摘Integrated sensor combines multiple sensor functions into a single unit,which has the advantages of miniaturization and better application potential.However,limited by the sensing platforms of the sensor and the selectivity of the sensitive film,there are still challenges to realize multi-component gas detection in one unit.Herein,a principle integration method is proposed to achieve the multi-component gas detection based on the acoustics-electricity-mechanics coupling effect.The electrical and mechanical properties of the Bi_(2)S_(3)nanobelts materials in different atmospheres indicate the possibility of realizing the principle integration.At the same time,the surface acoustic wave(SAW)sensor as a multivariable physical transducer can sense both electrical and mechanical properties.Upon exposure to 10 ppm NO_(2),NH_(3),and their mixtures,the integrated SAW gas sensor shows a 4.5 kHz positive frequency shift(acoustoelectric effect),an 11 kHz negative frequency shift(mechanics effects),and a reduced 4 kHz negative frequency shift(acoustics-electricity-mechanics coupling effect),respectively.Moreover,we realize wireless passive detection of NO_(2)and NH_(3)based on the SAW sensor.Our work provides valuable insights that can serve as a guide to the design and fabrication of single sensors offering multi-component gas detection via different gas sensing mechanisms.
基金W.D.acknowledges the National Key Research and Development Plan(2021YFA1202100)the Nature Science Foundation of Hubei province(20223564/2022CFB595)and China(52202134)+3 种基金2021 Independent Innovation Fund-New Teacher Research Starting Fund of Huazhong University of Science and Technology(5003182109)the Innovation Fund of WNLO,2022 Shenzhen Central Leading Local Science and Technology Development Special Funding Program Virtual University Park Laboratory ProjectQ.F.acknowledges the Natural Science Founda-tion of China(61971459)Shenzhen Technology Plan(JCYJ20190809095009521).
文摘The scale-free ferroelectric polarization of fluorite MO_(2)(M=Hf,Zr)due to flat polar phonon bands are promising for nonvolatile memories.Defects are also widely introduced to improve the emergent ferroelectricity.However,their roles are still not fully understood at the atomic-level.Here,we report a significant effect of point-defect-driven flattening of polar phonon bands with more polar modes and polarization contribution in doped MO_(2).The polar phonon bands in La-doped MO_(2)(M=Hf,Zr)can be significantly flattened,compared with pure ones.However,the lower energy barrier with larger polarization of VO-only doped MO_(2) compared with La-doped cases suggest that VO and local lattice distortion should be balanced for high-performance fluorite ferroelectricity.The work is believed to bridge the relation between point defects and the generally enhanced induced ferroelectricity in fluorite ferroelectrics at the atomic-level and inspire their further property optimization via defect-engineering.
基金supported by the National Science Foundation of China(Grant No.51972125,51772108,51972126 and 61675076)the Fund from Science,Technology and Innovation Commission of Shenzhen Municipality(JCYJ20180507182248925)+5 种基金the Innovation Fund of WNLO and the Fundamental Research Funds for the Central Universities(2019KFYRCPY126 and 2018KFYYXJJ052)the support from the Thousand Young Talent Program(Grant No.BE0200005)the support provided by the“Double First-Rate”Program(Grant No.WF220402017)the Prospective Research Program(Grant No.AF0200246)the Student Innovation Center at Shanghai Jiao Tong Universitysupported by the Key Research Program of Frontier Sciences,CAS(ZDBS-LY-JSC002).
文摘Electrocaloric effect(ECE)is promising in realizing solid-state cooling as an alternative to the conventional refrigeration with environmentally harmful coolant and low efficiency.High ECE in lead-free ferroelectric ceramics is highly desirable for the EC cooling.In this work,different from the researches that tune the ECE by conventional compositional design or external stress engineering,we fabricated the(1-x)BaTiO_(3)-xNaNbO_(3)(BTO-xNN)lead-free ceramics with a core-shell grain structure arising from the inhomogeneous stoichiometry of element distribution,leading to the internal compressing stress in the grains.It is interesting that the phase transition behavior,including the phase transition temperature and the diffusion property,is regulated by the core-shell grain structure induced internal stress,which can be capitalized on for the favorable ECE.Cooperated with 0.02 NN,a high ECE,e.g.adiabatic temperature change(ΔT)of 3.6 K and isothermal entropy change(ΔS)of 4.5 J kg^(-1) K^(-1),is attained in the BTO ceramic.As the internal stress further increases with more NN,the BTO-0.06NN exhibits an extremely stable ECE with a variety rate below ±4% in a wide temperature range from 300 K to 360 K.This work provides a novel approach to explore pronounced ECE in lead-free ferroelectrics for eco-friendly refrigeration.
基金supported by the National Natural Science Foundation of China(Grant Nos.51872053,52272105,and 52202130)the Guangdong Provincial Natural Science Foundation(Grant No.2015A030308004)+3 种基金the NSFC–Guangdong Joint Fund(Grant No.U1501246)the Dongguan City Frontier Research Project(Grant No.2019622101006)the Advanced Energy Science and Technology Guangdong Provincial Laboratory Foshan Branch–Foshan Xianhu Laboratory Open Fund-Key Project(Grant No.XHT2020-011)the Open Project Program of Guangdong Provincial Key Laboratory of Electronic Functional Materials and Devices,Huizhou University(Grant No.EFMD2022004Z).
文摘Solid-state cooling technology based on electrocaloric effect(ECE)has been advanced as an alternative to replace the vapour-compression approach to overcome the releasing of the global warming gases.However,the development in high ECE materials is still a challenge.In this work,polarization merging strategy was proposed to achieve a large ECE in xBa(Sn_(0.07)Ti_(0.93))O_(3)–(1−x)Ba(Hf_(0.1)Ti_(0.9))O_(3) ferroelectric ceramics,where x=0,0.2,0.4,0.6,0.8,and 1.Ba(Sn_(0.07)Ti_(0.93))O_(3) with an orthorhombic phase and Ba(Hf_(0.1)Ti_(0.9))O_(3) with a rhombohedral phase at room temperature were prepared beforehand as precursors,and phase-coexisted xBSnT–(1−x)BHfT ceramics were formed via a solid-state reaction approach.Phase coexisting structures were confirmed using the X-ray diffraction.The merged polarization was confirmed by the dielectric and ferroelectric properties.Optimal ECEs were obtained for 0.2BSnT–0.8BHfT ceramics,i.e.,adiabatic temperature change DT=2.16±0.08 K at 80℃and 5 MV/m,and DT=3.35±0.09 K at 80℃and 7 MV/m.