The A_(2)B_(2)O_(7)-type rare earth zirconate compounds have been considered as promising candidates for thermal barrier coating(TBC) materials because of their low sintering rate,improved phase stability,and reduced ...The A_(2)B_(2)O_(7)-type rare earth zirconate compounds have been considered as promising candidates for thermal barrier coating(TBC) materials because of their low sintering rate,improved phase stability,and reduced thermal conductivity in contrast with the currently used yttria-partially stabilized zirconia (YSZ) in high operating temperature environments.This review summarizes the recent progress on rare earth zirconates for TBCs that insulate high-temperature gas from hot-section components in gas turbines.Based on the first principles,molecular dynamics,and new data-driven calculation approaches,doping and high-entropy strategies have now been adopted in advanced TBC materials design.In this paper,the solid-state heat transfer mechanism of TBCs is explained from two aspects,including heat conduction over the full operating temperature range and thermal radiation at medium and high temperature.This paper also provides new insights into design considerations of adaptive TBC materials,and the challenges and potential breakthroughs are further highlighted for extreme environmental applications.Strategies for improving thermophysical performance are proposed in two approaches:defect engineering and material compositing.展开更多
Regulation of perovskite growth plays a critical role in the development of high-performance optoelectronic devices.However,judicious control of the grain growth for perovskite light emitting diodes is elusive due to ...Regulation of perovskite growth plays a critical role in the development of high-performance optoelectronic devices.However,judicious control of the grain growth for perovskite light emitting diodes is elusive due to its multiple requirements in terms of morphology,composition,and defect.Herein,we demonstrate a supramolecular dynamic coordination strategy to regulate perovskite crystallization.The combined use of crown ether and sodium trifluoroacetate can coordinate with A site and B site cations in ABX_(3) perovskite,respectively.The formation of supramolecular structure retard perovskite nucleation,while the transformation of supramolecular intermediate structure enables the release of components for slow perovskite growth.This judicious control enables a segmented growth,inducing the growth of insular nanocrystal consist of low-dimensional structure.Light emitting diode based on this perovskite film eventually brings a peak external quantum efficiency up to 23.9%,ranking among the highest efficiency achieved.The homogeneous nano-island structure also enables high-efficiency large area(1 cm^(2))device up to 21.6%,and a record high value of 13.6%for highly semi-transparent ones.展开更多
基金the financial support from the National Natural Science Foundation of China(Nos.51572061,51621091,and 51321061)the Heilongjiang Touyan Team Program。
文摘The A_(2)B_(2)O_(7)-type rare earth zirconate compounds have been considered as promising candidates for thermal barrier coating(TBC) materials because of their low sintering rate,improved phase stability,and reduced thermal conductivity in contrast with the currently used yttria-partially stabilized zirconia (YSZ) in high operating temperature environments.This review summarizes the recent progress on rare earth zirconates for TBCs that insulate high-temperature gas from hot-section components in gas turbines.Based on the first principles,molecular dynamics,and new data-driven calculation approaches,doping and high-entropy strategies have now been adopted in advanced TBC materials design.In this paper,the solid-state heat transfer mechanism of TBCs is explained from two aspects,including heat conduction over the full operating temperature range and thermal radiation at medium and high temperature.This paper also provides new insights into design considerations of adaptive TBC materials,and the challenges and potential breakthroughs are further highlighted for extreme environmental applications.Strategies for improving thermophysical performance are proposed in two approaches:defect engineering and material compositing.
基金The authors gratefully acknowledge financial support from the National Natural Science Foundation of China(Nos.61935016,92056119,22175118,62288102,62274135)National Key Research and Development Program of China(under Grants No.2021YFA0715502)+2 种基金Double First-Class Initiative Fund of ShanghaiTech University,and the Science and Technology Commission of Shanghai Municipality(Nos.20XD1402500 and 20JC1415800)Bertil och Britt Svenssons Stiftelse and Swedish Energy Agency(P2022-00394)The authors appreciate the Instrument Analysis Center and Centre for High-resolution Electron Microscopy(CħEM)and the high-performance computing(HPC)Platform of ShanghaiTech University.The authors gratefully thank professor John A.McGuire for the helpful discussion.
文摘Regulation of perovskite growth plays a critical role in the development of high-performance optoelectronic devices.However,judicious control of the grain growth for perovskite light emitting diodes is elusive due to its multiple requirements in terms of morphology,composition,and defect.Herein,we demonstrate a supramolecular dynamic coordination strategy to regulate perovskite crystallization.The combined use of crown ether and sodium trifluoroacetate can coordinate with A site and B site cations in ABX_(3) perovskite,respectively.The formation of supramolecular structure retard perovskite nucleation,while the transformation of supramolecular intermediate structure enables the release of components for slow perovskite growth.This judicious control enables a segmented growth,inducing the growth of insular nanocrystal consist of low-dimensional structure.Light emitting diode based on this perovskite film eventually brings a peak external quantum efficiency up to 23.9%,ranking among the highest efficiency achieved.The homogeneous nano-island structure also enables high-efficiency large area(1 cm^(2))device up to 21.6%,and a record high value of 13.6%for highly semi-transparent ones.
基金the National Key Research and Development Program of China(2016YFA0204000)the National Natural Science Foundation of China(61935016,U1632118 and 21571129)+3 种基金start-up funding from ShanghaiTech Universitythe Center for High-resolution Electron Microscopy(C?EM)at ShanghaiTech University(EM02161943)Young 1000 Talents ProgramScience Fund for Creative Research Groups(21421004)。
