The AA5052 aluminum alloy is widely used in automobile and aerospace manufacturing,and with the development of light-weight alloys,it is required that these materials exhibit better mechanical properties.Previous stud...The AA5052 aluminum alloy is widely used in automobile and aerospace manufacturing,and with the development of light-weight alloys,it is required that these materials exhibit better mechanical properties.Previous studies have demonstrated that the addition of Sc to aluminum alloys can improve both the microstructure and properties of the alloys.In this study,the effect of Sc on the Fe-rich phase and properties of the AA5052 aluminum alloy was studied by adding 0%,0.05%,0.2%,and 0.3%Sc.The results show that with the increase of Sc,the coarse needle-like Fe-rich phase gradually transforms into Chinese-script and then nearly spherical particles,reduce the size of Fe-rich phase,and refine the grain with increase of high angle grain boundaries(HAGBs).These microstructure changes enhance the strength of the AA5052 alloy through Sc addition.The ductility of the alloy is obviously improved because the addition of a lower amount of Sc changes the morphology of Fe-rich phase from needle-like into a Chinese-script,and it is subsequently reduced as a result of significant increase in HAGBs with increasing Sc content.展开更多
Rechargeable aluminum batteries(RABs)are attractive cadidates for next-generation energy storage and conversion,due to the low cost and high safety of Al resources,and high capacity of metal Al based on the three-elec...Rechargeable aluminum batteries(RABs)are attractive cadidates for next-generation energy storage and conversion,due to the low cost and high safety of Al resources,and high capacity of metal Al based on the three-electrons reaction mechanism.However,the development of RABs is greatly limited,because of the lack of advanced cathode materials,and their complicated and unclear reaction mechanisms.Exploring the novel nanostructured transition metal and carbon composites is an effective route for obtaining ideal cathode materials.In this work,we synthesize porous CoSnO_(3)/C nanocubes with oxygen vacancies for utilizing as cathodes in RABs for the first time.The intrinsic structure stability of the mixed metal cations and carbon coating can improve the cycling performance of cathodes by regulating the internal strains of the electrodes during volume expansion.The nanocubes with porous structures contribute to fast mass transportation which improves the rate capability.In addition to this,abundant oxygen vacancies promote the adsorption affinity of cathodes,which improves storage capacity.As a result,the CoSnO_(3)/C cathodes display an excellent reversible capacity of 292.1 mAh g^(-1) at 0.1 A g^(-1),a good rate performance with 109 mAh g^(-1) that is maintained even at 1 A g^(-1) and the provided stable cycling behavior for 500 cycles.Besides,a mechanism of intercalation of Al^(3+)within CoSnO_(3)/C cathode is proposed for the electrochemical process.Overall,this work provides a step toward the development of advanced cathode materials for RABs by engineering novel nanostructured mixed transition-metal oxides with carbon composite and proposes novel insights into chemistry for RABs.展开更多
Nowadays,OLEDs have shown aesthetic potential in smart cards,sensor displays,other electronic devices,sensitive medical devices and signal monitoring etc.due to their wide range of applications like low power consumpt...Nowadays,OLEDs have shown aesthetic potential in smart cards,sensor displays,other electronic devices,sensitive medical devices and signal monitoring etc.due to their wide range of applications like low power consumption,high contrast ratio,speed highly electroluminescent,wide viewing angle and fast response time.In this paper,a highly efficient organic LED ITO/V_(2)O_(5)/Alq3/TPBi/BPhen/LiF/Al with low turn-on voltage and high optically efficiency is presented including electrical and optical characteristics.The simulation of electrical characteristics like current versus applied voltage,current density versus applied voltage,recombination prefactor versus excess carrier density characteristics and optical characteristics like light flux versus current density,light flux versus applied voltage and optical efficiency versus applied voltage has been explained.The physical design,working principle and thickness of different layers along with the process of formation of singlet and triplet excitons are discussed in detail.Here double electron transport layer(ETL),cathode layers are used to enhance the electrical and optical efficiency of OLED.The operating voltage is found to be~3.2 V for the ITO/V_(2)O_(5)/Alq3/TPBi/BPhen/LiF/Al heterostructure based OLED.The designed organic LED has achieved the maximum optical efficiency at 3 V.展开更多
基金supported by the Key Research&Development Program of Yunnan Province(Grant numbers 202103AA080017,202203AE140011).
文摘The AA5052 aluminum alloy is widely used in automobile and aerospace manufacturing,and with the development of light-weight alloys,it is required that these materials exhibit better mechanical properties.Previous studies have demonstrated that the addition of Sc to aluminum alloys can improve both the microstructure and properties of the alloys.In this study,the effect of Sc on the Fe-rich phase and properties of the AA5052 aluminum alloy was studied by adding 0%,0.05%,0.2%,and 0.3%Sc.The results show that with the increase of Sc,the coarse needle-like Fe-rich phase gradually transforms into Chinese-script and then nearly spherical particles,reduce the size of Fe-rich phase,and refine the grain with increase of high angle grain boundaries(HAGBs).These microstructure changes enhance the strength of the AA5052 alloy through Sc addition.The ductility of the alloy is obviously improved because the addition of a lower amount of Sc changes the morphology of Fe-rich phase from needle-like into a Chinese-script,and it is subsequently reduced as a result of significant increase in HAGBs with increasing Sc content.
基金supported by the National Natural Science Foundation of China (Grant No.22075028).
文摘Rechargeable aluminum batteries(RABs)are attractive cadidates for next-generation energy storage and conversion,due to the low cost and high safety of Al resources,and high capacity of metal Al based on the three-electrons reaction mechanism.However,the development of RABs is greatly limited,because of the lack of advanced cathode materials,and their complicated and unclear reaction mechanisms.Exploring the novel nanostructured transition metal and carbon composites is an effective route for obtaining ideal cathode materials.In this work,we synthesize porous CoSnO_(3)/C nanocubes with oxygen vacancies for utilizing as cathodes in RABs for the first time.The intrinsic structure stability of the mixed metal cations and carbon coating can improve the cycling performance of cathodes by regulating the internal strains of the electrodes during volume expansion.The nanocubes with porous structures contribute to fast mass transportation which improves the rate capability.In addition to this,abundant oxygen vacancies promote the adsorption affinity of cathodes,which improves storage capacity.As a result,the CoSnO_(3)/C cathodes display an excellent reversible capacity of 292.1 mAh g^(-1) at 0.1 A g^(-1),a good rate performance with 109 mAh g^(-1) that is maintained even at 1 A g^(-1) and the provided stable cycling behavior for 500 cycles.Besides,a mechanism of intercalation of Al^(3+)within CoSnO_(3)/C cathode is proposed for the electrochemical process.Overall,this work provides a step toward the development of advanced cathode materials for RABs by engineering novel nanostructured mixed transition-metal oxides with carbon composite and proposes novel insights into chemistry for RABs.
文摘Nowadays,OLEDs have shown aesthetic potential in smart cards,sensor displays,other electronic devices,sensitive medical devices and signal monitoring etc.due to their wide range of applications like low power consumption,high contrast ratio,speed highly electroluminescent,wide viewing angle and fast response time.In this paper,a highly efficient organic LED ITO/V_(2)O_(5)/Alq3/TPBi/BPhen/LiF/Al with low turn-on voltage and high optically efficiency is presented including electrical and optical characteristics.The simulation of electrical characteristics like current versus applied voltage,current density versus applied voltage,recombination prefactor versus excess carrier density characteristics and optical characteristics like light flux versus current density,light flux versus applied voltage and optical efficiency versus applied voltage has been explained.The physical design,working principle and thickness of different layers along with the process of formation of singlet and triplet excitons are discussed in detail.Here double electron transport layer(ETL),cathode layers are used to enhance the electrical and optical efficiency of OLED.The operating voltage is found to be~3.2 V for the ITO/V_(2)O_(5)/Alq3/TPBi/BPhen/LiF/Al heterostructure based OLED.The designed organic LED has achieved the maximum optical efficiency at 3 V.