Battery safety is influenced by various factors,with thermal runaway being one of the most significant concerns.While most studies have concentrated on developing one-time,self-activating mechanism for thermal protect...Battery safety is influenced by various factors,with thermal runaway being one of the most significant concerns.While most studies have concentrated on developing one-time,self-activating mechanism for thermal protection,such as temperature-responsive electrodes,and thermal-shutdown separators,these methods only provide irreversible protection.Recently,reversible temperature-sensitive electrolytes have emerged as promising alternatives,offering both thermo-reversibility and self-protective properties.However,further research is crucial to fully understand these thermal-shutdown electrolytes.In this study,we propose lower critical solution temperature(LCST)phase behavior poly(benzyl methacrylate)/imidazolium-based ionic liquid mixtures to prepare temperature-sensitive electrolytes that provide reversible thermal shutdown protection of batteries.This electrolyte features an appropriate protection temperature(~105℃)and responds quickly within a 1 min at 105℃,causing cells to hardly discharge as the voltage suddenly drops to 3.38 V,and providing efficient thermal shutdown protection within 30 min.Upon cooling back to room temperature,the battery regains its original performance.Additionally,the electrolyte exhibits excellent cycling stability with the capacity retention of the battery is 91.6%after 500 cycles.This work provides a viable solution for preventing batteries from thermal runaway triggered by overheating.展开更多
With the exponential growth of the internet of things,artificial intelligence,and energy-efficient high-volume data digital communications,there is an urgent demand to develop new information technologies with high st...With the exponential growth of the internet of things,artificial intelligence,and energy-efficient high-volume data digital communications,there is an urgent demand to develop new information technologies with high storage capacity.This needs to address the looming challenge of conventional Von Neumann architecture and Moore's law bottleneck for future data-intensive computing applications.A promising remedy lies in memristors,which offer distinct advantages of scalability,rapid access times,stable data retention,low power consumption,multistate storage capability and fast operation.Among the various materials used for active layers in memristors,low dimensional perovskite semiconductors with structural diversity and superior stability exhibit great potential for next generation memristor applications,leveraging hysteresis characteristics caused by ion migration and defects.In this review the progress of low-dimensional perovskite memory devices is comprehensively summarized.The working mechanism and fundamental processes,including ion migration dynamics,charge carrier transport and electronic resistance that underlies the switching behavior of memristors are discussed.Additionally,the device parameters are analyzed with special focus on the effective methods to improve electrical performance and operational stability.Finally,the challenges and perspective on major hurdles of low-dimensional perovskite memristors in the expansive application domains are provided.展开更多
The early stages of crystallization and occurrence of surface wrinkling were investigated using poly(butadiene)-block-poly(ε-caprolactone)with an ordered lamellar structure.Direct evidence has demonstrated that surfa...The early stages of crystallization and occurrence of surface wrinkling were investigated using poly(butadiene)-block-poly(ε-caprolactone)with an ordered lamellar structure.Direct evidence has demonstrated that surface wrinkling precedes nucleation and crystal growth.This study examined the relationship between surface wrinkling,nucleation,and the formation of crystalline supramolecular structures using atomic force microscopy(AFM)and X-ray scattering measurements.Surface wrinkling is attributed to curving induced by accumulated stresses,including residual stress from the sample preparation and thermal stress during cooling.These stresses cause large-scale material flow and corresponding changes in the molecular conformations,potentially reducing the nucleation barrier.This hypothesis is supported by the rapid crystal growth observed following the spread of surface wrinkles.Additionally,the surface curving of the polymer thin film creates local minima of the free energy,facilitating nucleation.The nuclei subsequently grow into crystalline supramolecular structures by incorporating polymer molecules from the melt.This mechanism highlights the role of localized structural inhomogeneity in the early stages of crystallization and provides new insights into structure formation processes.展开更多
On the basis of the association theory of nuclear structure, we have studied the （t, p） reaction. Study was carried out with the distorted plane waves of triton and of proton. It has been suggested that bineutron as...On the basis of the association theory of nuclear structure, we have studied the （t, p） reaction. Study was carried out with the distorted plane waves of triton and of proton. It has been suggested that bineutron association is acceptable if the time during which the association maintains its structure, is large compared with the time when neutrons are in a dissociated form, and there is no exchange of nucleons between fragments associations. The cross section is written as a product of two factors, one is the spectroscopic factor which reflects the nature of the nuclear structure concerned and the other describes the process in which the target nucleus captures two nucleons as a cluster into an orbit which is characterized by a form factor. In the argument, that the radial wave function of two neutrons which form association captured nuclei close to each other, this leads to the formation of bineutron association on the nuclei surface. In this approach, the proton is emitted at the same point, which is captured bineutron association.展开更多
Perovskite solar cells(PSCs)have emerged as a promising candidate for next-generation photovoltaic devices and offer potential applications as an alternative to conventional fossil fuels.Over the past decade,solution-...Perovskite solar cells(PSCs)have emerged as a promising candidate for next-generation photovoltaic devices and offer potential applications as an alternative to conventional fossil fuels.Over the past decade,solution-processable organic-inorganic halide perovskites have achieved remarkable power-conversion efficiencies(PCEs),comparable to those of their silicon counterparts,owing to their high absorption coefficients and charge densities[1,2].Notably,integrating wide-bandgap(WBG)perovskites with silicon solar cells to construct perovskite/silicon tandem solar cells(PSTs)renders a significant commercial potential,with recent advances resulting in the PCEs of PSTs exceeding 33%[3].However,despite rapid improvements in PCEs,WBG PSCs,which function as the top cell in PSTs,exhibit unsatisfactory crystallinity and a weak texture with disordered orientations,resulting in phase segregation and mixed halide-cation ion migration[4].展开更多
基金funded by the National Natural Science Foundation of China(no.22075155)the Zhejiang Provincial Natural Science Foundation of China(No.LY24B030002)+2 种基金Ningbo Natural Science Foundation(2023J089)the China Scholarship Council(CSC)the Ningbo Science and Technology Bureau(2024QL036).
文摘Battery safety is influenced by various factors,with thermal runaway being one of the most significant concerns.While most studies have concentrated on developing one-time,self-activating mechanism for thermal protection,such as temperature-responsive electrodes,and thermal-shutdown separators,these methods only provide irreversible protection.Recently,reversible temperature-sensitive electrolytes have emerged as promising alternatives,offering both thermo-reversibility and self-protective properties.However,further research is crucial to fully understand these thermal-shutdown electrolytes.In this study,we propose lower critical solution temperature(LCST)phase behavior poly(benzyl methacrylate)/imidazolium-based ionic liquid mixtures to prepare temperature-sensitive electrolytes that provide reversible thermal shutdown protection of batteries.This electrolyte features an appropriate protection temperature(~105℃)and responds quickly within a 1 min at 105℃,causing cells to hardly discharge as the voltage suddenly drops to 3.38 V,and providing efficient thermal shutdown protection within 30 min.Upon cooling back to room temperature,the battery regains its original performance.Additionally,the electrolyte exhibits excellent cycling stability with the capacity retention of the battery is 91.6%after 500 cycles.This work provides a viable solution for preventing batteries from thermal runaway triggered by overheating.
基金supported by funding from the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)under Germany's Excellence Strategy-EXC 2089/1-390776260(e-conversion)via the International Research Training Group 2022 Alberta/Technical University of Munich International Graduate School for Environmentally Responsible Functional Hybrid Materials(ATUMS).
文摘With the exponential growth of the internet of things,artificial intelligence,and energy-efficient high-volume data digital communications,there is an urgent demand to develop new information technologies with high storage capacity.This needs to address the looming challenge of conventional Von Neumann architecture and Moore's law bottleneck for future data-intensive computing applications.A promising remedy lies in memristors,which offer distinct advantages of scalability,rapid access times,stable data retention,low power consumption,multistate storage capability and fast operation.Among the various materials used for active layers in memristors,low dimensional perovskite semiconductors with structural diversity and superior stability exhibit great potential for next generation memristor applications,leveraging hysteresis characteristics caused by ion migration and defects.In this review the progress of low-dimensional perovskite memory devices is comprehensively summarized.The working mechanism and fundamental processes,including ion migration dynamics,charge carrier transport and electronic resistance that underlies the switching behavior of memristors are discussed.Additionally,the device parameters are analyzed with special focus on the effective methods to improve electrical performance and operational stability.Finally,the challenges and perspective on major hurdles of low-dimensional perovskite memristors in the expansive application domains are provided.
基金the National Natural Science Foundation of China(Nos.U2032101 and 11905306)the National Key Research and Development Project of China(No.2022YFB2402602).
文摘The early stages of crystallization and occurrence of surface wrinkling were investigated using poly(butadiene)-block-poly(ε-caprolactone)with an ordered lamellar structure.Direct evidence has demonstrated that surface wrinkling precedes nucleation and crystal growth.This study examined the relationship between surface wrinkling,nucleation,and the formation of crystalline supramolecular structures using atomic force microscopy(AFM)and X-ray scattering measurements.Surface wrinkling is attributed to curving induced by accumulated stresses,including residual stress from the sample preparation and thermal stress during cooling.These stresses cause large-scale material flow and corresponding changes in the molecular conformations,potentially reducing the nucleation barrier.This hypothesis is supported by the rapid crystal growth observed following the spread of surface wrinkles.Additionally,the surface curving of the polymer thin film creates local minima of the free energy,facilitating nucleation.The nuclei subsequently grow into crystalline supramolecular structures by incorporating polymer molecules from the melt.This mechanism highlights the role of localized structural inhomogeneity in the early stages of crystallization and provides new insights into structure formation processes.
文摘On the basis of the association theory of nuclear structure, we have studied the （t, p） reaction. Study was carried out with the distorted plane waves of triton and of proton. It has been suggested that bineutron association is acceptable if the time during which the association maintains its structure, is large compared with the time when neutrons are in a dissociated form, and there is no exchange of nucleons between fragments associations. The cross section is written as a product of two factors, one is the spectroscopic factor which reflects the nature of the nuclear structure concerned and the other describes the process in which the target nucleus captures two nucleons as a cluster into an orbit which is characterized by a form factor. In the argument, that the radial wave function of two neutrons which form association captured nuclei close to each other, this leads to the formation of bineutron association on the nuclei surface. In this approach, the proton is emitted at the same point, which is captured bineutron association.
基金support from PolyU Distinguished Postdoc Fellowship(1-YW4C)support from Research Grants Council of Hong Kong(Project nos.15221320,15307922,C7018-20G,C5037-18G,and C4005-22Y)+4 种基金the RGC Senior Research Fellowship Scheme(SRFS2223-5S01)the Shenzhen Science and Technology Innovation Commission(JCYJ20200109105003940)the Hong Kong Polytechnic University:Sir Sze-yuen Chung Endowed Professorship Fund(8-8480)RISE(Q-CDBK),PRI(Q-CD7X)the Guangdong-Hong Kong-Macao Joint Laboratory for Photonic-Thermal-Electrical Energy Materials and Devices(GDSTC no.2019B121205001).
文摘Perovskite solar cells(PSCs)have emerged as a promising candidate for next-generation photovoltaic devices and offer potential applications as an alternative to conventional fossil fuels.Over the past decade,solution-processable organic-inorganic halide perovskites have achieved remarkable power-conversion efficiencies(PCEs),comparable to those of their silicon counterparts,owing to their high absorption coefficients and charge densities[1,2].Notably,integrating wide-bandgap(WBG)perovskites with silicon solar cells to construct perovskite/silicon tandem solar cells(PSTs)renders a significant commercial potential,with recent advances resulting in the PCEs of PSTs exceeding 33%[3].However,despite rapid improvements in PCEs,WBG PSCs,which function as the top cell in PSTs,exhibit unsatisfactory crystallinity and a weak texture with disordered orientations,resulting in phase segregation and mixed halide-cation ion migration[4].
