BiMeO_(3)–PbTiO_(3)(where Me represents transition metals)perovskite-type thin films have been widely studied due to their superior ferroelectric properties,including robust ferroelectric polarization and high Curie ...BiMeO_(3)–PbTiO_(3)(where Me represents transition metals)perovskite-type thin films have been widely studied due to their superior ferroelectric properties,including robust ferroelectric polarization and high Curie temperatures.In this study,PbTiO_(3)-based perovskite thin films of xBi(Cu_(1/2)Zr_(1/2))O_(3)–(1-x)PbTiO_(3)(xBCZ–(1-x)PT)were designed and prepared on Pt(111)/Ti/SiO_(2)/Si substrates using the conventional sol–gel method.The x BCZ–(1-x)PT thin films demonstrate remarkable crystallinity,characterized by a perovskite structure and a dense microstructure,which contribute to their highperformance ferroelectric and fatigue properties.Notably,the thin films exhibit large remnant polarization(2P_(r0))values,reaching 98μC·cm^(-2)and 74μC·cm^(-2)for the 0.05BCZ–0.95PT and 0.1BCZ–0.9PT compositions,respectively.Furthermore,the thin films also demonstrate a high Curie temperature(T_(C)=510℃),as well as favorable fatigue properties and low leakage current,suggesting their potential applicability in ferroelectric devices.展开更多
The establishment of multi-component catalytic systems on Fe2O3 photoanodes presents considerable potential for significantly enhancing the performance of photoelectrochemical water splitting systems. In this study, w...The establishment of multi-component catalytic systems on Fe2O3 photoanodes presents considerable potential for significantly enhancing the performance of photoelectrochemical water splitting systems. In this study, we hydrothermally synthesized a Fe2O3 photoanode. In addition, d-Fe OOH synthesized via dip-coating and hydrothermally prepared h-FeOOH were used as cocatalysts and their synergistic combinations with cobalt phosphate(Co-Pi) were investigated. The synergy between h-FeOOH and Co-Pi was remarkable, whereas that between d-Fe OOH and Co-Pi was negligible. For example, the onset potentials of the Co-Pi/h-FeOOH and Co-Pi/d-FeOOH dual catalysts, were cathodically shifted by 270 and 170 m V, respectively. Moreover, the photocurrent density of the Co-Pi/h-FeOOH/Fe2O3 anode was significantly higher than that of the Co-Pi/d-FeOOH/Fe2O3 one. The synergistic effect of Co-Pi and h-FeOOH could be attributed to the significantly inhibited recombination of surface charges owing to the formation of a p-n junction between β-FeOOH and Fe2O3 and the large contact area between the granular h-FeOOH and Co-Pi. However, the thin amorphous FeOOH layer of the Co-Pi/d-FeOOH/Fe2O3 anode acted as a hole-transfer medium, and weakly promoted the kinetics of the charge transfer process.展开更多
Generally,most materials expand when heated and contract when cooled,whereas negative thermal expansion(NTE)materials are very rare.As a typical NTE material,PbTiO_(3) and related compounds have drawn particular inter...Generally,most materials expand when heated and contract when cooled,whereas negative thermal expansion(NTE)materials are very rare.As a typical NTE material,PbTiO_(3) and related compounds have drawn particular interest in recent years.The discovery of an enhanced NTE system in PbTiO_(3) is beneficial to deepen our understanding of its mechanism and regulate its properties.At present,the method of discriminating an enhanced NTE material based on PbTiO_(3) is not universal.Here,we propose a semi-empirical method through evaluating the average lattice distortion in related systems to estimate the relative coefficient of thermal expansion conveniently.The rationality of the method was verified by the analysis of the 0.6PbTiO_(3)-0.4Bi(Ga_(x)Fe_(1-x))O_(3) system.So far,all PbTiO_(3)-based compounds with enhanced NTE conform well to this method.This method provides the possibility to find more enhanced NTE PbTiO_(3)-based materials.展开更多
The direct one-step separation of polymer-grade C_(2)H_(4) from complex light hydrocarbon mixtures has high industrial significance but is very challenging.Herein,an ethylene-adsorption-weakening strategy is applied f...The direct one-step separation of polymer-grade C_(2)H_(4) from complex light hydrocarbon mixtures has high industrial significance but is very challenging.Herein,an ethylene-adsorption-weakening strategy is applied for precise regulation of the pore geometry of four tailor-made metal–organic frameworks(MOFs)with pillar-layered structures,dubbed TYUT-10/11/12/13.Based on its pore geometry design and functional group regulation,TYUT-12 exhibits exceptional selective adsorption selectivity toward C_(3)H_(8),C_(3)H_(6),C_(2)H_(6),C_(2)H_(2),and CO_(2) over C_(2)H_(4);its C_(2)H_(6)/C_(2)H_(4) adsorption selectivity reaches 4.56,surpassing the record value of 4.4 by Fe_(2)(O_(2))(dobdc)(dobdc^(4-)=2,5-dioxido-1,4-benzenedicarboxylate).The weak p–p stacking binding affinity toward C_(2)H_(4) in TYUT-12 is clearly demonstrated through a combination of neutron powder diffraction measurements and theoretical calculations.Breakthrough experiments demonstrate that C_(2)H_(4) can be directly obtained from binary,ternary,quaternary,and six-component light hydrocarbon mixtures with over 99.95%purity.展开更多
Synthetic biology is an interdisciplinary field that combines engineering principles to design and construct new biological components,devices,and systems for understanding and reprogramming biological functions.This ...Synthetic biology is an interdisciplinary field that combines engineering principles to design and construct new biological components,devices,and systems for understanding and reprogramming biological functions.This field aims to create novel biological entities with specific functions or solutions to particular problems through precise manipulation of biomolecules and cells.Bladder cancer is a type of cancer that originates in the tissues of the urinary bladder and primarily affects the urothelial cells lining the bladder wall.Synthetic biology technology,while relatively new for the treatment of bladder cancer,has promising potential for providing innovative solutions for the detection,treatment,and management of bladder cancer.This article reviews the latest research progress in the field of synthetic biology applied to bladder cancer.This research focuses on the application of gene editing technologies such as CRISPR-CRISPR-associated protein 9 to precisely modify the genome of bladder cancer cells to inhibit their growth and proliferation.Additionally,it introduces methods for enhancing antitumor immune responses through the modification of immune cells,such as chimeric antigen receptor-T-cell therapy.Furthermore,this article explores the potential of the use of genetically engineered bacteria as an emerging treatment option for bladder cancer.Despite challenges such as targeting specificity,safety,and cost,synthetic biology technologies provide new perspectives and strategies for the treatment of bladder cancer.With continuous advancements in technology and strengthened interdisciplinary collaboration,the application of synthetic biology in bladder cancer treatment holds great promise,potentially offering patients new treatment options and hope.展开更多
Development of piezoelectric materials through chemical design meets the requirement of the nextgeneration electronic devices,yet the sensitive piezoelectricity to both chemical components and operational environment ...Development of piezoelectric materials through chemical design meets the requirement of the nextgeneration electronic devices,yet the sensitive piezoelectricity to both chemical components and operational environment call for the trial and error method during material preparation.In order to give an atomic-level understanding about functional unit and assist the chemical design,deep learning was applied to train a novelmodel based on themost popular BaTiO3 system,as a case study in this work.Through training the atomic force field of calcium and stannum doped solid-solution with Deep Potential method,3D structure of chemical distribution and corresponding polarization configuration can be constructed for different compositions under different temperatures,which exhibits a high degree of consistency with the local structure quantitatively analyzed from HAADF STEM and reverse Monte Carlo refinement of neutron total scattering data,especially for the critical composition with ultrahigh piezoelectricity of d33~860 pC/N.Systemic analysis reveals that variations in chemical bond length among various elements with oxygen elements are the primary factors influencing ferroelectric activity and leading to structural evolution.The results and methodology can facilitate the discovery of new ferroelectrics and the design of high-performance piezo/ferroelectrics with atomic-level insights.展开更多
Negative thermal expansion(NTE),where materials contract rather than expand with temperature rise,is crucial for applications requiring thermal stability,and its regulation holds significant technological promise.This...Negative thermal expansion(NTE),where materials contract rather than expand with temperature rise,is crucial for applications requiring thermal stability,and its regulation holds significant technological promise.This work demonstrates that nanosizing Cu_(2)P_(2)O_(7) through high-energy ball milling suppresses its NTE by 30.6%,with the average volumetric thermal expansion coefficient decreasing from−27.69×10^(−6) K^(−1)(bulk,5-375 K)to−19.20×10^(−6) K^(−1)(nano,87-440 K),while broadening the NTE temperature range by 65 K.Structural analyses reveal that reduced distortion of CuO_(4) polyhedra in nanocrystals slows theα-to-βphase transition,mitigating NTE.The study highlights nanosizing as an effective strategy to tune NTE in phase-transition materials by alleviating internal stress,offering a novel approach for thermal expansion regulation.展开更多
This article reported the diagnosis and treatment of cystitis glandularis(CG)co-occurring with bladder neck leiomyomas.We retrospectively analyzed the clinical data of a single case of CG with bladder neck leiomyoma.A...This article reported the diagnosis and treatment of cystitis glandularis(CG)co-occurring with bladder neck leiomyomas.We retrospectively analyzed the clinical data of a single case of CG with bladder neck leiomyoma.A 31-year-old Chinese woman wasgiven a diagnosis of CG and bladder neck leiomyoma.The mass and surrounding bladder mucosal lesions were entirely excisedvia transurethral resection,leaving a clean margin of healthy tissue.Histopathological analyses confirmed the diagnosis of CG andbladder neck leiomyoma.The patient remained asymptomatic throughout the follow-up period,with no indication of recurrence.Cystitis glandularis co-occurring with bladder neck leiomyoma requires careful examination,and surgery remains the best treatmentoption for these diseases.展开更多
PbTiO_(3)-BiMeO_(3)ferroelectrics have attracted much attention due to not only their extremely large polarization and piezoelectricity but also their controllable thermal expansion.In this study,we present a new bina...PbTiO_(3)-BiMeO_(3)ferroelectrics have attracted much attention due to not only their extremely large polarization and piezoelectricity but also their controllable thermal expansion.In this study,we present a new binary system of(1-x)PbTio_(3)-xBi(Cu_(0.5)Ti_(0.5))o_(3)possessing large tetragonality and enhanced spontaneous polarization.Interestingly,a combination of near zero thermal expansion and negative thermal expansion over a temperature range of RT to TC(550℃)has been observed in tetragonal 0.85PbTio_(3)-0.15Bi(Cu_(0.5)Ti_(0.5))o_(3).The comprehensive structure analysis addressed that the abnormal thermal expansion is coupled to the spontaneous volume ferroelectrostriction.Moreover,the chemical bonding investigation by a maximum entropy method further attests that the covalent hybridization of Pb/Bi–o bonds plays a vital role in the improved ferroelectricity and interacts with thermal vibration to dominate the crossover from positive to negative thermal expansion.The present studies would give direct evidence to verify the theoretical calculations and could be extended to reveal the nature of thermal expansion in ferroelectrics.展开更多
The extraordinary performances of phase-coexisting ferroelectrics are significantly affected by not only the phase constitution but also the motion of domain walls.The study on the role of phase coexistence in the for...The extraordinary performances of phase-coexisting ferroelectrics are significantly affected by not only the phase constitution but also the motion of domain walls.The study on the role of phase coexistence in the formation of ferroelectric and ferroelastic domain microstructures is of great importance to explain the enhanced piezoelectric properties.In situ high-energy diffraction and the Rayleigh law are utilized to reveal the interplay of phase constitution and domain configuration to the macroscopic electromechanical coupling effect in the morphotropic phase boundary composition of 0.365BiScO_(3)–0.635PbTiO_(3) during the application of a weak electrical loading in the present study.It was found that anisotropic phase transition and domain switching occur in polycrystalline ferroelectric ceramics and a phase transition occurs dramatically beyond the coercive field.Taking into account the important role of coupled ferroelectric and ferroelastic domain microstructures,we conceived a configuration of monoclinic domains coexisting with and bridging the tetragonal domains.The existence of bridging domains would provide an insight into the interplay of the phase and domain and explains the piezoelectric performance in the vicinity of morphotropic phase boundaries.展开更多
To meet the increasing demand for high temperature piezoelectric actuator and transducer applications,much attention has been paid on exploring piezoelectric materials which can work efficiently under high temperature...To meet the increasing demand for high temperature piezoelectric actuator and transducer applications,much attention has been paid on exploring piezoelectric materials which can work efficiently under high temperature conditions.In the present study,a new Bi-based perovskite(ABO_(3))of(1-x)PbTiO_(3)-xBi(Zn_(1/2)Hf_(1/2))O_(3)has been investigated.For the compositions of x<0.20,it is interesting to observe that the tetragonality(c/a)remains relatively constant over the entire tetragonal phase.This unusual phenomenon is in contrast to the behavior of most PbTiO_(3)-based solid solutions,wherein the c/a is usually reduced.As a result,the Curie temperature(TC)increases from 490℃for pure PbTiO_(3),to as high as 528℃for x=0.10,indicating the present PbTiO_(3)-Bi(Zn_(1/2)Hf_(1/2))O_(3)to be a high-TC piezoelectric material.It is proposed that the maintained large tetragonality and high TC could be attributed to the large spontaneous polarization(PS)displacements induced by the strong Pb/Bi-O hybridization and coupling interactions between Pb/Bi and B-site ferroelectricactive cations.展开更多
It is known that negative thermal expansion(NTE)in PbTiO_(3)(PT)ferroelectrics can be controlled by chemical substitutions.In the present work,however,we report a method to change the NTE of PT by introducing cation d...It is known that negative thermal expansion(NTE)in PbTiO_(3)(PT)ferroelectrics can be controlled by chemical substitutions.In the present work,however,we report a method to change the NTE of PT by introducing cation deficiency at both the A(Pb^(2+))and B sites(Ti^(4+)).We investigated the spontaneous polarization,tetragonality c/a,coefficient of thermal expansion,and Curie temperature T_(C) with 8%Pb^(2+)deficient PT(P_(92)T),2%Ti^(4+)deficient PT(PT_(98)),and pure PT.We found that while Pb^(2+)deficiency distinctively weakens the NTE,the effect of B-site deficiency could be ignored.These phenomena are ascribed to the NTE mechanism of spontaneous volume ferroelectrostriction.The present study provides a possible way to control the NTE of PT-based materials.展开更多
PbTiO_(3)–Bi(Zn_(1/2)Ti_(1/2))O_(3)is considered to be a promising high-ferroelectric performance material in the Pb/Bi-based perovskite family.In the present study,a whole set of(1−x)PbTiO_(3)–xBi(Zn_(1/2)Ti_(1/2))...PbTiO_(3)–Bi(Zn_(1/2)Ti_(1/2))O_(3)is considered to be a promising high-ferroelectric performance material in the Pb/Bi-based perovskite family.In the present study,a whole set of(1−x)PbTiO_(3)–xBi(Zn_(1/2)Ti_(1/2))O_(3)(0≤x≤1)solid solutions have been prepared by the conventional solid-state and high-pressure vs.hightemperature methods.The effect of Bi(Zn_(1/2)Ti_(1/2))O_(3) on the crystal structure has been investigated by synchrotron X-ray powder diffraction.Unlike most PbTiO_(3)-based perovskites,the present system exhibits a continuously enhanced tetragonality(c/a)and large spontaneous polarization(P_(S))properties.The enhanced c/a is ascribed to the large spontaneous polarization displacements induced by the strong Pb/Bi–O hybridization and coupling interactions between Ti/Zn and Pb/Bi cations,which can be evidenced from the lattice dynamics study and first-principles calculations.Accordingly,the T_(C)(i.e.,x=0.5)is expected to be approximately 1000℃ if its perovskite structure can be stabilized.The present study provides a route to obtain large-P_(S) in PbTiO_(3-)based ferroelectric materials by introducing isostructural perovskites with strong polarity.展开更多
Electrochemically converting CO_(2)to value-added multi-carbon(C_(2+))fuels and chemicals is a favorable way to achieve carbon neutrality.Herein,polyaniline/CuO nanosheets(PANI/CuO NSs)hybrid electrocatalysts are deve...Electrochemically converting CO_(2)to value-added multi-carbon(C_(2+))fuels and chemicals is a favorable way to achieve carbon neutrality.Herein,polyaniline/CuO nanosheets(PANI/CuO NSs)hybrid electrocatalysts are developed in order to achieve superior C_(2+)selectivity by imparting PANI functional component to the CuO NSs.The decorated PANI nanoparticles(NPs)can effectively stabilize the*CO intermediates and increase their coverage on the active Cu sites,which facilitates the C-C coupling to form multi-carbon products.Benefiting from the synergetic effect of PANI and CuO NSs,best Faradaic efficiency(FE)for C_(2+)product up to 66.4%at-1.6 V vs.reversible hydrogen electrode(RHE)in a H-cell measurement and 60.0%at 400 mA·cm^(-2)in a flow cell measurement are demonstrated by PANI/CuO NSs-25 sample.More importantly,the C_(2+)selectivity keeps stable even in a continuous measurement time period of 92 h in H-cell measurement.The present study may provide more insights for designing efficient hybrid materials toward superior C_(2+)production from electrocatalytic CO_(2)reduction.展开更多
Imposing phase engineering to porous materials is promising to realize outperforming electrocatalytic performances by taking advantages of the merits of porous nanoarchitecture and heterophase structure.In this work,a...Imposing phase engineering to porous materials is promising to realize outperforming electrocatalytic performances by taking advantages of the merits of porous nanoarchitecture and heterophase structure.In this work,amorphous/crystalline ruthenium oxide(RuO_(2))porous particles with rationally regulated heterophases are successfully prepared by integrating the phase engineering into the porous material synthesis.The resultant defect-rich amorphous/crystalline RuO_(2)porous particles exhibit excellent electrocatalytic performance toward the oxygen evolution reaction,achieving a low overpotential of 165 mV at a current density of 10 mA·cm^(−2)and a high mass activity up to 133.8 mA·cm^(-2)at a low overpotential of 200 mV.This work indicates that the synergistic effect of amorphous/crystalline heterophase and porous structural characteristics enables RuO_(2)to trigger a superior electrocatalytic activity.展开更多
基金Project supported by the National Key Research and Development Program of China(Grant No.2021YFA1400300)the National Natural Science Foundation of China(Grant Nos.22271309,12304268,12261131499,and 11921004)the China Postdoctoral Science Foundation(Grant No.2023M743741)。
文摘BiMeO_(3)–PbTiO_(3)(where Me represents transition metals)perovskite-type thin films have been widely studied due to their superior ferroelectric properties,including robust ferroelectric polarization and high Curie temperatures.In this study,PbTiO_(3)-based perovskite thin films of xBi(Cu_(1/2)Zr_(1/2))O_(3)–(1-x)PbTiO_(3)(xBCZ–(1-x)PT)were designed and prepared on Pt(111)/Ti/SiO_(2)/Si substrates using the conventional sol–gel method.The x BCZ–(1-x)PT thin films demonstrate remarkable crystallinity,characterized by a perovskite structure and a dense microstructure,which contribute to their highperformance ferroelectric and fatigue properties.Notably,the thin films exhibit large remnant polarization(2P_(r0))values,reaching 98μC·cm^(-2)and 74μC·cm^(-2)for the 0.05BCZ–0.95PT and 0.1BCZ–0.9PT compositions,respectively.Furthermore,the thin films also demonstrate a high Curie temperature(T_(C)=510℃),as well as favorable fatigue properties and low leakage current,suggesting their potential applicability in ferroelectric devices.
文摘The establishment of multi-component catalytic systems on Fe2O3 photoanodes presents considerable potential for significantly enhancing the performance of photoelectrochemical water splitting systems. In this study, we hydrothermally synthesized a Fe2O3 photoanode. In addition, d-Fe OOH synthesized via dip-coating and hydrothermally prepared h-FeOOH were used as cocatalysts and their synergistic combinations with cobalt phosphate(Co-Pi) were investigated. The synergy between h-FeOOH and Co-Pi was remarkable, whereas that between d-Fe OOH and Co-Pi was negligible. For example, the onset potentials of the Co-Pi/h-FeOOH and Co-Pi/d-FeOOH dual catalysts, were cathodically shifted by 270 and 170 m V, respectively. Moreover, the photocurrent density of the Co-Pi/h-FeOOH/Fe2O3 anode was significantly higher than that of the Co-Pi/d-FeOOH/Fe2O3 one. The synergistic effect of Co-Pi and h-FeOOH could be attributed to the significantly inhibited recombination of surface charges owing to the formation of a p-n junction between β-FeOOH and Fe2O3 and the large contact area between the granular h-FeOOH and Co-Pi. However, the thin amorphous FeOOH layer of the Co-Pi/d-FeOOH/Fe2O3 anode acted as a hole-transfer medium, and weakly promoted the kinetics of the charge transfer process.
基金financially supported by the National Key R&D Program of China(No.2020YFA0406202)the National Natural Science Foundation of China(Nos.22090042 and 21731001)。
文摘Generally,most materials expand when heated and contract when cooled,whereas negative thermal expansion(NTE)materials are very rare.As a typical NTE material,PbTiO_(3) and related compounds have drawn particular interest in recent years.The discovery of an enhanced NTE system in PbTiO_(3) is beneficial to deepen our understanding of its mechanism and regulate its properties.At present,the method of discriminating an enhanced NTE material based on PbTiO_(3) is not universal.Here,we propose a semi-empirical method through evaluating the average lattice distortion in related systems to estimate the relative coefficient of thermal expansion conveniently.The rationality of the method was verified by the analysis of the 0.6PbTiO_(3)-0.4Bi(Ga_(x)Fe_(1-x))O_(3) system.So far,all PbTiO_(3)-based compounds with enhanced NTE conform well to this method.This method provides the possibility to find more enhanced NTE PbTiO_(3)-based materials.
基金supported by National Key Research and Development Program of China(2022YFB3806800)National Natural Science Foundation of China(22278288 and 22090062).
文摘The direct one-step separation of polymer-grade C_(2)H_(4) from complex light hydrocarbon mixtures has high industrial significance but is very challenging.Herein,an ethylene-adsorption-weakening strategy is applied for precise regulation of the pore geometry of four tailor-made metal–organic frameworks(MOFs)with pillar-layered structures,dubbed TYUT-10/11/12/13.Based on its pore geometry design and functional group regulation,TYUT-12 exhibits exceptional selective adsorption selectivity toward C_(3)H_(8),C_(3)H_(6),C_(2)H_(6),C_(2)H_(2),and CO_(2) over C_(2)H_(4);its C_(2)H_(6)/C_(2)H_(4) adsorption selectivity reaches 4.56,surpassing the record value of 4.4 by Fe_(2)(O_(2))(dobdc)(dobdc^(4-)=2,5-dioxido-1,4-benzenedicarboxylate).The weak p–p stacking binding affinity toward C_(2)H_(4) in TYUT-12 is clearly demonstrated through a combination of neutron powder diffraction measurements and theoretical calculations.Breakthrough experiments demonstrate that C_(2)H_(4) can be directly obtained from binary,ternary,quaternary,and six-component light hydrocarbon mixtures with over 99.95%purity.
文摘Synthetic biology is an interdisciplinary field that combines engineering principles to design and construct new biological components,devices,and systems for understanding and reprogramming biological functions.This field aims to create novel biological entities with specific functions or solutions to particular problems through precise manipulation of biomolecules and cells.Bladder cancer is a type of cancer that originates in the tissues of the urinary bladder and primarily affects the urothelial cells lining the bladder wall.Synthetic biology technology,while relatively new for the treatment of bladder cancer,has promising potential for providing innovative solutions for the detection,treatment,and management of bladder cancer.This article reviews the latest research progress in the field of synthetic biology applied to bladder cancer.This research focuses on the application of gene editing technologies such as CRISPR-CRISPR-associated protein 9 to precisely modify the genome of bladder cancer cells to inhibit their growth and proliferation.Additionally,it introduces methods for enhancing antitumor immune responses through the modification of immune cells,such as chimeric antigen receptor-T-cell therapy.Furthermore,this article explores the potential of the use of genetically engineered bacteria as an emerging treatment option for bladder cancer.Despite challenges such as targeting specificity,safety,and cost,synthetic biology technologies provide new perspectives and strategies for the treatment of bladder cancer.With continuous advancements in technology and strengthened interdisciplinary collaboration,the application of synthetic biology in bladder cancer treatment holds great promise,potentially offering patients new treatment options and hope.
基金supported by the National Key R&D Program of China(Grant No.2023YFB3508200)the Outstanding Young Scientist Program of Beijing Colleges and Universities(JWZQ20240101015)the National Natural Science Foundation of China(Grant Nos.92370104,22235002 and 52172181).We acknowledge the computational resource from Beijing PARATERA Tech Corp,LTD.
文摘Development of piezoelectric materials through chemical design meets the requirement of the nextgeneration electronic devices,yet the sensitive piezoelectricity to both chemical components and operational environment call for the trial and error method during material preparation.In order to give an atomic-level understanding about functional unit and assist the chemical design,deep learning was applied to train a novelmodel based on themost popular BaTiO3 system,as a case study in this work.Through training the atomic force field of calcium and stannum doped solid-solution with Deep Potential method,3D structure of chemical distribution and corresponding polarization configuration can be constructed for different compositions under different temperatures,which exhibits a high degree of consistency with the local structure quantitatively analyzed from HAADF STEM and reverse Monte Carlo refinement of neutron total scattering data,especially for the critical composition with ultrahigh piezoelectricity of d33~860 pC/N.Systemic analysis reveals that variations in chemical bond length among various elements with oxygen elements are the primary factors influencing ferroelectric activity and leading to structural evolution.The results and methodology can facilitate the discovery of new ferroelectrics and the design of high-performance piezo/ferroelectrics with atomic-level insights.
基金supported by the Outstanding Young Scientist Program of Beijing Colleges and Universities(No.JWZQ20240101015)the Fundamental Research Funds for the Central Universities,China(No.FRF-TP-22-137A1)+1 种基金We acknowledge the BL02B2 beamline of the SPring-8 synchrotron radiation facility,Japan,as well as all the staff for the technical assistance.The authors acknowledge ELETTRA Synchrotron Trieste for the provision of beamtime(experiment No.20230135)as well as all the staff of the XAFS beamline.We acknowledge Prof.Xianran Xing of Institute of Solid State Chemistry,University of Science and Technology Beijing provides laboratory X-ray diffraction(PANalytical X’Pert PRO X-ray diffractometer,Cu Kα1 radiation,λ=1.54059Å)testing.
文摘Negative thermal expansion(NTE),where materials contract rather than expand with temperature rise,is crucial for applications requiring thermal stability,and its regulation holds significant technological promise.This work demonstrates that nanosizing Cu_(2)P_(2)O_(7) through high-energy ball milling suppresses its NTE by 30.6%,with the average volumetric thermal expansion coefficient decreasing from−27.69×10^(−6) K^(−1)(bulk,5-375 K)to−19.20×10^(−6) K^(−1)(nano,87-440 K),while broadening the NTE temperature range by 65 K.Structural analyses reveal that reduced distortion of CuO_(4) polyhedra in nanocrystals slows theα-to-βphase transition,mitigating NTE.The study highlights nanosizing as an effective strategy to tune NTE in phase-transition materials by alleviating internal stress,offering a novel approach for thermal expansion regulation.
文摘This article reported the diagnosis and treatment of cystitis glandularis(CG)co-occurring with bladder neck leiomyomas.We retrospectively analyzed the clinical data of a single case of CG with bladder neck leiomyoma.A 31-year-old Chinese woman wasgiven a diagnosis of CG and bladder neck leiomyoma.The mass and surrounding bladder mucosal lesions were entirely excisedvia transurethral resection,leaving a clean margin of healthy tissue.Histopathological analyses confirmed the diagnosis of CG andbladder neck leiomyoma.The patient remained asymptomatic throughout the follow-up period,with no indication of recurrence.Cystitis glandularis co-occurring with bladder neck leiomyoma requires careful examination,and surgery remains the best treatmentoption for these diseases.
基金supported by the National Natural Science Foundation of China(Grant No.21701126,21801013,21825102,21731001,21590793)the Talent Introduction Foundation of Tianjin Normal University(5RL146)+1 种基金the Fundamental Research Funds for the Central Universities,China(Grant No.FRF-TP-18-001C2).L.L.Fthanks the financial support from the China Scholarship Council.
文摘PbTiO_(3)-BiMeO_(3)ferroelectrics have attracted much attention due to not only their extremely large polarization and piezoelectricity but also their controllable thermal expansion.In this study,we present a new binary system of(1-x)PbTio_(3)-xBi(Cu_(0.5)Ti_(0.5))o_(3)possessing large tetragonality and enhanced spontaneous polarization.Interestingly,a combination of near zero thermal expansion and negative thermal expansion over a temperature range of RT to TC(550℃)has been observed in tetragonal 0.85PbTio_(3)-0.15Bi(Cu_(0.5)Ti_(0.5))o_(3).The comprehensive structure analysis addressed that the abnormal thermal expansion is coupled to the spontaneous volume ferroelectrostriction.Moreover,the chemical bonding investigation by a maximum entropy method further attests that the covalent hybridization of Pb/Bi–o bonds plays a vital role in the improved ferroelectricity and interacts with thermal vibration to dominate the crossover from positive to negative thermal expansion.The present studies would give direct evidence to verify the theoretical calculations and could be extended to reveal the nature of thermal expansion in ferroelectrics.
基金supported by the National Natural Science Foundation of China(Grants 21701126,21801013,21825102,21731001,and 21590793)the Fundamental Research Funds for the Central Universities,China(Grant FRF-TP-18-001C2)+3 种基金financial support from the China Scholarship Council and the help from Naike ShiNSF’s ChemMatCARS Sector 15 is principally supported by the Divisions of Chemistry(CHE)Materials Research(DMR),National Science Foundation,under Grant No.NSF/CHE-1834750The use of the Advanced Photon Source,an Office of Science User Facility operated for the U.S.Department of Energy(DOE)Office of Science by Argonne National Laboratory,was supported by the U.S.DOE under Contract No.DE-AC02-06CH11357.
文摘The extraordinary performances of phase-coexisting ferroelectrics are significantly affected by not only the phase constitution but also the motion of domain walls.The study on the role of phase coexistence in the formation of ferroelectric and ferroelastic domain microstructures is of great importance to explain the enhanced piezoelectric properties.In situ high-energy diffraction and the Rayleigh law are utilized to reveal the interplay of phase constitution and domain configuration to the macroscopic electromechanical coupling effect in the morphotropic phase boundary composition of 0.365BiScO_(3)–0.635PbTiO_(3) during the application of a weak electrical loading in the present study.It was found that anisotropic phase transition and domain switching occur in polycrystalline ferroelectric ceramics and a phase transition occurs dramatically beyond the coercive field.Taking into account the important role of coupled ferroelectric and ferroelastic domain microstructures,we conceived a configuration of monoclinic domains coexisting with and bridging the tetragonal domains.The existence of bridging domains would provide an insight into the interplay of the phase and domain and explains the piezoelectric performance in the vicinity of morphotropic phase boundaries.
基金supported by the National Natural Science Foundation of China(Grants 21322102,21590793,91422301,and 21231001)the National Program for Support of Top-notch Young Professionals,the Program for Chang Jiang Young Scholars,and the Fundamental Research Funds for the Central Universities,China(Grant FRF-TP-14-012C1)Advanced Photon Source,a U.S.Department of Energy(DOE)Office of Science User Facility,operated for the DOE Office of Science by the Argonne National Laboratory under Contract DE-AC02-06CH11357.
文摘To meet the increasing demand for high temperature piezoelectric actuator and transducer applications,much attention has been paid on exploring piezoelectric materials which can work efficiently under high temperature conditions.In the present study,a new Bi-based perovskite(ABO_(3))of(1-x)PbTiO_(3)-xBi(Zn_(1/2)Hf_(1/2))O_(3)has been investigated.For the compositions of x<0.20,it is interesting to observe that the tetragonality(c/a)remains relatively constant over the entire tetragonal phase.This unusual phenomenon is in contrast to the behavior of most PbTiO_(3)-based solid solutions,wherein the c/a is usually reduced.As a result,the Curie temperature(TC)increases from 490℃for pure PbTiO_(3),to as high as 528℃for x=0.10,indicating the present PbTiO_(3)-Bi(Zn_(1/2)Hf_(1/2))O_(3)to be a high-TC piezoelectric material.It is proposed that the maintained large tetragonality and high TC could be attributed to the large spontaneous polarization(PS)displacements induced by the strong Pb/Bi-O hybridization and coupling interactions between Pb/Bi and B-site ferroelectricactive cations.
基金supported by the National Natural Science Foundation of China(grant no.91022016,91422301,and 21231001)the Program for Changjiang Scholars and the Innovative Research Team in University(IRT1207)the Fundamental Research Funds for the Central Universities,China(grant no.FRF-SD-13-008A).
文摘It is known that negative thermal expansion(NTE)in PbTiO_(3)(PT)ferroelectrics can be controlled by chemical substitutions.In the present work,however,we report a method to change the NTE of PT by introducing cation deficiency at both the A(Pb^(2+))and B sites(Ti^(4+)).We investigated the spontaneous polarization,tetragonality c/a,coefficient of thermal expansion,and Curie temperature T_(C) with 8%Pb^(2+)deficient PT(P_(92)T),2%Ti^(4+)deficient PT(PT_(98)),and pure PT.We found that while Pb^(2+)deficiency distinctively weakens the NTE,the effect of B-site deficiency could be ignored.These phenomena are ascribed to the NTE mechanism of spontaneous volume ferroelectrostriction.The present study provides a possible way to control the NTE of PT-based materials.
基金supported by the National Natural Science Foundation of China(Grant No.21731001 and 21590793)the National Program for Support of Top-notch Young Professionals,the Program for Chang Jiang Young Scholars,the Fundamental Research Funds for the Central Universities,China(FRF-TP-17-001B)+2 种基金the General Financial Grant from the China Postdoctoral Science Foundation(2017M622536)Department of Energy(DOE)Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No.DE-AC02-06CH11357The room temperature synchrotron radiation experiments were also performed at the BL44B2 beamline of SPring-8 with the approval of the Japan Synchrotron Radiation Research Institute(JASRI)(Proposal NO.2016A1060).
文摘PbTiO_(3)–Bi(Zn_(1/2)Ti_(1/2))O_(3)is considered to be a promising high-ferroelectric performance material in the Pb/Bi-based perovskite family.In the present study,a whole set of(1−x)PbTiO_(3)–xBi(Zn_(1/2)Ti_(1/2))O_(3)(0≤x≤1)solid solutions have been prepared by the conventional solid-state and high-pressure vs.hightemperature methods.The effect of Bi(Zn_(1/2)Ti_(1/2))O_(3) on the crystal structure has been investigated by synchrotron X-ray powder diffraction.Unlike most PbTiO_(3)-based perovskites,the present system exhibits a continuously enhanced tetragonality(c/a)and large spontaneous polarization(P_(S))properties.The enhanced c/a is ascribed to the large spontaneous polarization displacements induced by the strong Pb/Bi–O hybridization and coupling interactions between Ti/Zn and Pb/Bi cations,which can be evidenced from the lattice dynamics study and first-principles calculations.Accordingly,the T_(C)(i.e.,x=0.5)is expected to be approximately 1000℃ if its perovskite structure can be stabilized.The present study provides a route to obtain large-P_(S) in PbTiO_(3-)based ferroelectric materials by introducing isostructural perovskites with strong polarity.
文摘Electrochemically converting CO_(2)to value-added multi-carbon(C_(2+))fuels and chemicals is a favorable way to achieve carbon neutrality.Herein,polyaniline/CuO nanosheets(PANI/CuO NSs)hybrid electrocatalysts are developed in order to achieve superior C_(2+)selectivity by imparting PANI functional component to the CuO NSs.The decorated PANI nanoparticles(NPs)can effectively stabilize the*CO intermediates and increase their coverage on the active Cu sites,which facilitates the C-C coupling to form multi-carbon products.Benefiting from the synergetic effect of PANI and CuO NSs,best Faradaic efficiency(FE)for C_(2+)product up to 66.4%at-1.6 V vs.reversible hydrogen electrode(RHE)in a H-cell measurement and 60.0%at 400 mA·cm^(-2)in a flow cell measurement are demonstrated by PANI/CuO NSs-25 sample.More importantly,the C_(2+)selectivity keeps stable even in a continuous measurement time period of 92 h in H-cell measurement.The present study may provide more insights for designing efficient hybrid materials toward superior C_(2+)production from electrocatalytic CO_(2)reduction.
文摘Imposing phase engineering to porous materials is promising to realize outperforming electrocatalytic performances by taking advantages of the merits of porous nanoarchitecture and heterophase structure.In this work,amorphous/crystalline ruthenium oxide(RuO_(2))porous particles with rationally regulated heterophases are successfully prepared by integrating the phase engineering into the porous material synthesis.The resultant defect-rich amorphous/crystalline RuO_(2)porous particles exhibit excellent electrocatalytic performance toward the oxygen evolution reaction,achieving a low overpotential of 165 mV at a current density of 10 mA·cm^(−2)and a high mass activity up to 133.8 mA·cm^(-2)at a low overpotential of 200 mV.This work indicates that the synergistic effect of amorphous/crystalline heterophase and porous structural characteristics enables RuO_(2)to trigger a superior electrocatalytic activity.
