Light alloys have irreplaceable advantages such as high specific strength and low density.They are indispensable structural materials in aerospace,military,and marine engineering.It is an enduring research hotspot to ...Light alloys have irreplaceable advantages such as high specific strength and low density.They are indispensable structural materials in aerospace,military,and marine engineering.It is an enduring research hotspot to prepare high-strength and high-toughness light alloys to play a more significant role in advanced engineering applications.As a new method to improve the mechanical properties of light alloys,the magnetic field-assisted process can produce magnetoplastic effects.Therefore,in this paper,research progress on the magnetoplastic effects of light alloys assisted by magnetic fields was reviewed,and the effects of magnetic fields on dislocations,grain refinement,precipitation kinetics,phase transformation,and mechanical properties of light alloys were elucidated.Magnetic field treatment transforms radical pairs from the ground state to the excited state,which reduces the resistance between dislocations and obstacles,facilitating dislocation depinning.Moreover,magnetic field can promote grain refinement and phase transformation,increase precipitation kinetics,and synergistically improve strength and elongation.Finally,the prospects of magnetic field-assisted processes of light alloys were discussed.展开更多
Carrier separation in a solar cell usually relies on the p–n junction. Here we show that an n–n type inorganic semiconductor heterojunction is also able to separate the exciton for efficient solar cell applications....Carrier separation in a solar cell usually relies on the p–n junction. Here we show that an n–n type inorganic semiconductor heterojunction is also able to separate the exciton for efficient solar cell applications. The n–n type heterojunction was formed by hydrothermal deposition of Sb_(2)(S,Se)_(3) and thermal evaporation of Sb_(2)Se_(3). We found that the n–n junction is able to enhance the carrier separation by the formation of an electric field, reduce the interfacial recombination and generate optimized band alignment. The device based on this n–n junction shows 2.89% net efficiency improvement to 7.75%when compared with the device consisted of semiconductor absorber–metal contact. The study in the n–n type solar cell is expected to bring about more versatile materials utility, new interfacial engineering strategy and fundamental findings in the photovoltaic energy conversion process.展开更多
The mechanical behavior of solution heat-treated and pre-aged Mg–6Zn–1Gd–1Er alloys during hot compression(from 180 to 330℃)has been investigated.The results showed that the flow stress curves of the pre-aged samp...The mechanical behavior of solution heat-treated and pre-aged Mg–6Zn–1Gd–1Er alloys during hot compression(from 180 to 330℃)has been investigated.The results showed that the flow stress curves of the pre-aged sample(PAS)intersected with that of the solution heat-treated sample(SHTS)during hot compression.At 180℃,when the true strain is 0.27 and 0.47,the PAS showed larger and smaller stress(210.80 MPa vs.207.58 MPa and 205.67 MPa vs.207.93 MPa)than the SHTS,respectively.These phenomena were due to the stronger interaction of W phase and dislocations/twins under the strain of 0.27,while dynamic recrystallization softening occurred under the strain of 0.47.When the temperature increased to 330℃,the flow stress of PAS and SHTS showed an opposite trend to that of 180℃.Continuous dynamic recrystallization and particle stimulated nucleation based on slip operations are the main deformation mechanisms under 330℃.At the true strain is 0.33 and 0.53,the PAS has smaller and larger stress(61.32 MPa vs.63.69 MPa and 58.75 MPa vs.57.09 MPa)than the SHTS,respectively.The increasing deformation resistance of dynamic precipitation improved the flow stress under smaller strain and dynamic recrystallization decreased the flow stress under high strain,which resulted the opposite phenomena of SHTS.展开更多
Antimony selenide(Sb_(2)Se_(3))has recently made considerable photovoltaic,advancements in photoelectrochemical,and photodetector research scenarios,owing to its advantageous material merits and superior optoelectroni...Antimony selenide(Sb_(2)Se_(3))has recently made considerable photovoltaic,advancements in photoelectrochemical,and photodetector research scenarios,owing to its advantageous material merits and superior optoelectronic properties.By contrast,the exploration of flexible Sb_(2)Se_(3) photoelectric devices are less attempted,though it possesses unique one-dimensional(1D)crystal structure to enable large deformation tolerance.Here,we develop a flexible Sb2Ses thin-film photodetector on polyimide substrate.Thanks to the high-quality SbSes light absorber and benign interfaces at both back contact and heterojunction regions,the carrier dynamics are effectively optimized.The leading flexible Sb_(2)Se_(3) photodetector showcases self-powered and broadband features,with exceptional responsivity of 0.51 A·W^(-1) and realistic detectivity up to 1.32×10^(13) Jones,ultra-fast response speed of 49 ns/351 ns of rise and decay times,and remarkable mechanical deformation stability,flourishing the high-level development for flexible Sb_(2)Se_(3) photodetectors.Interestingly,a tunable single/dual-color flexible imaging system under band alignment modulation,along with a wearable and accurate heart rate/arterial blood oxygen saturation photoplethysmography detection system highlights the great application potential for flexible Sb,Ses photodetectors.展开更多
Hydrothermal deposition of antimony selenosulfide(Sb_(2)(S,Se_(3)))has enabled solar cell applications to surpass the 10%efficiency threshold.This deposition process involves the reaction of three precursor materials:...Hydrothermal deposition of antimony selenosulfide(Sb_(2)(S,Se_(3)))has enabled solar cell applications to surpass the 10%efficiency threshold.This deposition process involves the reaction of three precursor materials:Sb,S,and Se.However,this process generates an unfavourable gradient of Se and S anions in the Sb_(2)(S,Se)_(3)film,which limits further efficiency improvements.Herein,we demonstrate how NH_(4)F can be used as an additive to regulate the band gradient of the Sb_(2)(S,Se)_(3)and modify the surface of the CdS electron-transporting layer.On the one hand,NH_(4)F inhibits the decomposition of Na_(2)S_(2)O_(3)and selenourea,which optimizes the deposition process and allows for adjustment of the Se/S ratio and their distribution in the Sb_(2)(S,Se)_(3)film.On the other hand,hydrolysis of NH_(4)F induces dissolution and redeposition of CdS,thereby effectively improving the morphology and crystallinity of the CdS substrate.Finally,the dual effect of NH_(4)F enables improved surface morphology and energy alignment of the Sb_(2)(S,Se)_(3)film,thus yielding a maximum efficiency of 10.28%,a 12%improvement over the control device.This study demonstrates an effective strategy for simultaneously modifying a sulfide-based substrate and regulating the element distribution during the deposition of a metal chalcogenide film for optoelectronic device applications.展开更多
基金supported by the National Natural Science Foundation of China(No.52274382)the National Key Research and Development Program of China(No.2023YFB3407000).
文摘Light alloys have irreplaceable advantages such as high specific strength and low density.They are indispensable structural materials in aerospace,military,and marine engineering.It is an enduring research hotspot to prepare high-strength and high-toughness light alloys to play a more significant role in advanced engineering applications.As a new method to improve the mechanical properties of light alloys,the magnetic field-assisted process can produce magnetoplastic effects.Therefore,in this paper,research progress on the magnetoplastic effects of light alloys assisted by magnetic fields was reviewed,and the effects of magnetic fields on dislocations,grain refinement,precipitation kinetics,phase transformation,and mechanical properties of light alloys were elucidated.Magnetic field treatment transforms radical pairs from the ground state to the excited state,which reduces the resistance between dislocations and obstacles,facilitating dislocation depinning.Moreover,magnetic field can promote grain refinement and phase transformation,increase precipitation kinetics,and synergistically improve strength and elongation.Finally,the prospects of magnetic field-assisted processes of light alloys were discussed.
基金Project supported by Institute of Energy, Hefei Comprehensive National Science Center (Grant No. 21KZS212)the National Key Research and Development Program of China (Grant No. 2019YFA0405600)+2 种基金the National Natural Science Foundation of China (Grant Nos. U19A2092 and 22005293)the China Postdoctoral Science Foundation (Grant No. 2021M693045)Collaborative Innovation Program of Hefei Science Center, Chinese Academy of Sciences。
文摘Carrier separation in a solar cell usually relies on the p–n junction. Here we show that an n–n type inorganic semiconductor heterojunction is also able to separate the exciton for efficient solar cell applications. The n–n type heterojunction was formed by hydrothermal deposition of Sb_(2)(S,Se)_(3) and thermal evaporation of Sb_(2)Se_(3). We found that the n–n junction is able to enhance the carrier separation by the formation of an electric field, reduce the interfacial recombination and generate optimized band alignment. The device based on this n–n junction shows 2.89% net efficiency improvement to 7.75%when compared with the device consisted of semiconductor absorber–metal contact. The study in the n–n type solar cell is expected to bring about more versatile materials utility, new interfacial engineering strategy and fundamental findings in the photovoltaic energy conversion process.
基金supported by the National Natural Science Foundation of China(Grant Nos.52174362,51975207,and 11772127)the Hunan Provincial Natural Science Foundation for Excellent Young Scholars of China(Grant No.2019JJ30010)+2 种基金the Hunan Provincial Natural Science Foundation of China(Grant No.2018JJ3101)the Scientific Research Fund of Hunan Provincial Education Department(Grant No.17B059)the Leading Plan for Scientific and Technological Innovation of High-Tech Industries—Heavy Haul Equipment R&D and Intelligent Handling(No.2021GK4008).
文摘The mechanical behavior of solution heat-treated and pre-aged Mg–6Zn–1Gd–1Er alloys during hot compression(from 180 to 330℃)has been investigated.The results showed that the flow stress curves of the pre-aged sample(PAS)intersected with that of the solution heat-treated sample(SHTS)during hot compression.At 180℃,when the true strain is 0.27 and 0.47,the PAS showed larger and smaller stress(210.80 MPa vs.207.58 MPa and 205.67 MPa vs.207.93 MPa)than the SHTS,respectively.These phenomena were due to the stronger interaction of W phase and dislocations/twins under the strain of 0.27,while dynamic recrystallization softening occurred under the strain of 0.47.When the temperature increased to 330℃,the flow stress of PAS and SHTS showed an opposite trend to that of 180℃.Continuous dynamic recrystallization and particle stimulated nucleation based on slip operations are the main deformation mechanisms under 330℃.At the true strain is 0.33 and 0.53,the PAS has smaller and larger stress(61.32 MPa vs.63.69 MPa and 58.75 MPa vs.57.09 MPa)than the SHTS,respectively.The increasing deformation resistance of dynamic precipitation improved the flow stress under smaller strain and dynamic recrystallization decreased the flow stress under high strain,which resulted the opposite phenomena of SHTS.
基金This work was supported by the National Natural Science Foundation of China(Nos.62104156,62074102,22275180,and 2019YFA0405600)Guangdong Basic and Applied Basic Research Foundation(Nos.2023A1515011256 and 2022A1515010979)ChinaShenzhen Science and Technology Program(No.GJHZ20240218113809019).
文摘Antimony selenide(Sb_(2)Se_(3))has recently made considerable photovoltaic,advancements in photoelectrochemical,and photodetector research scenarios,owing to its advantageous material merits and superior optoelectronic properties.By contrast,the exploration of flexible Sb_(2)Se_(3) photoelectric devices are less attempted,though it possesses unique one-dimensional(1D)crystal structure to enable large deformation tolerance.Here,we develop a flexible Sb2Ses thin-film photodetector on polyimide substrate.Thanks to the high-quality SbSes light absorber and benign interfaces at both back contact and heterojunction regions,the carrier dynamics are effectively optimized.The leading flexible Sb_(2)Se_(3) photodetector showcases self-powered and broadband features,with exceptional responsivity of 0.51 A·W^(-1) and realistic detectivity up to 1.32×10^(13) Jones,ultra-fast response speed of 49 ns/351 ns of rise and decay times,and remarkable mechanical deformation stability,flourishing the high-level development for flexible Sb_(2)Se_(3) photodetectors.Interestingly,a tunable single/dual-color flexible imaging system under band alignment modulation,along with a wearable and accurate heart rate/arterial blood oxygen saturation photoplethysmography detection system highlights the great application potential for flexible Sb,Ses photodetectors.
基金the National Natural Science Foundation of China(22005293 and U19A2092)the National Key Research and Development Program of China(2019YFA0405600).
文摘Hydrothermal deposition of antimony selenosulfide(Sb_(2)(S,Se_(3)))has enabled solar cell applications to surpass the 10%efficiency threshold.This deposition process involves the reaction of three precursor materials:Sb,S,and Se.However,this process generates an unfavourable gradient of Se and S anions in the Sb_(2)(S,Se)_(3)film,which limits further efficiency improvements.Herein,we demonstrate how NH_(4)F can be used as an additive to regulate the band gradient of the Sb_(2)(S,Se)_(3)and modify the surface of the CdS electron-transporting layer.On the one hand,NH_(4)F inhibits the decomposition of Na_(2)S_(2)O_(3)and selenourea,which optimizes the deposition process and allows for adjustment of the Se/S ratio and their distribution in the Sb_(2)(S,Se)_(3)film.On the other hand,hydrolysis of NH_(4)F induces dissolution and redeposition of CdS,thereby effectively improving the morphology and crystallinity of the CdS substrate.Finally,the dual effect of NH_(4)F enables improved surface morphology and energy alignment of the Sb_(2)(S,Se)_(3)film,thus yielding a maximum efficiency of 10.28%,a 12%improvement over the control device.This study demonstrates an effective strategy for simultaneously modifying a sulfide-based substrate and regulating the element distribution during the deposition of a metal chalcogenide film for optoelectronic device applications.
基金supported by the National Natural Science Foundation of China (22005293, U19A2092 and 22275180)the National Key Research and Development Program of China (2019YFA0405600)+1 种基金the Institute of Energy, Hefei Comprehensive National Science Center (21KZS212)the Collaborative Innovation Program of Hefei Science Center, CAS。
