The anisotropic two-dimensional （2D） layered material rhenium disulfide （ReSe2） has attracted considerable attention because of its unusual properties and promising applications in electronic and optoelectronic de...The anisotropic two-dimensional （2D） layered material rhenium disulfide （ReSe2） has attracted considerable attention because of its unusual properties and promising applications in electronic and optoelectronic devices. However, because of its low lattice symmetry and interlayer decoupling, anisotropic growth and out-of-plane growth occur easily, yielding thick flakes, dendritic structure, or flower-like structure. In this stud34 we demonstrated a bottom-up method for the controlled and scalable synthesis of ReSe2 by van der Waals epitaxy. To achieve controllable growth, a micro-reactor with a confined reaction space was constructed by stacking two mica substrates in the chemical vapor deposition system. Within the confined reaction space, the nucleation density and growth rate of ReSe2 were significantly reduced, favoring the large-area synthesis of ReSe2 with a uniform monolayer thickness. The morphological evolution of ReSe2 with growth temperature indicated that the anisotropic growth was suppressed at a low growth temperature （〈600 ℃）. Field-effect transistors employing the grown ReSe2 exhibited p-type conduction with a current ON/OFF ratio up to 10s and a hole carrier mobility of 0.98 cm^2/（V·s）. Furthermore, the ReSe2 device exhibited an outstanding photoresponse to near-infrared light, with responsivity up to 8.4 and 5.1 A/W for 850- and 940-nm light, respectively. This work not only promotes the large-scale application of ReSe2 in high-performance electronic devices but also clarifies the growth mechanism of low-lattice symmetry 2D materials.展开更多
Organic–inorganic metal halide perovskites have attained extensive attention owing to their outstanding photovoltaic performances,but the existence of numerous defects in crystalline perovskites is still a serious co...Organic–inorganic metal halide perovskites have attained extensive attention owing to their outstanding photovoltaic performances,but the existence of numerous defects in crystalline perovskites is still a serious constraint for the further development of perovskite solar cells(PSCs).In particular,the rapid crystallization guided by anti-solvents leads to plenty of surficial and interfacial defects in perovskite films.Herein,we report the adoption of a pseudo-halide anion based ionic liquid additive,1-butyl-3-methylimidazolium thiocyanate(BMIMSCN)for growing ternary cation(CsFAMA,where FA=formamidinium and MA=methylammonium)perovskites with large-scale crystal grains and strong preferential orientation via the enhanced Ostwald ripening.Meanwhile,a novel halide-free passivator,benzylammonium formate(BAFa),was employed as a buffering layer on the perovskite films to suppress surface-dominated charge recombination.As a result,the cooperative effects of BMIMSCN additive and BAFa passivator lead to significant enhancements on fluorescence lifetime(from 79.41 to 201.01 ns),open-circuit voltage(from 1.13 to 1.19 V),photoelectric conversion efficiency(from 18.90%to 22.33%).Moreover,the BMIMSCN/BAFa-CsFAMA PSCs demonstrated greatly improved stability against moisture and heat.This work suggests a promising strategy to improve the quality of perovskite materials via reducing the surficial and interfacial defects by the synergistic effects of lattice doping and interface engineering.展开更多
The safety valve is an important component to ensure the safe operation of lithium-ion batteries(LIBs).However,the effect of safety valve type on the thermal runaway(TR)and gas venting behavior of LIBs,as well as the ...The safety valve is an important component to ensure the safe operation of lithium-ion batteries(LIBs).However,the effect of safety valve type on the thermal runaway(TR)and gas venting behavior of LIBs,as well as the TR hazard severity of LIBs,are not known.In this paper,the TR and gas venting behavior of three 100 A h lithium iron phosphate(LFP)batteries with different safety valves are investigated under overheating.Compared to previous studies,the main contribution of this work is in studying and evaluating the effect of gas venting behavior and TR hazard severity of LFP batteries with three safety valve types.Two significant results are obtained:(Ⅰ)the safety valve type dominates over gas venting pressure of battery during safety venting,the maximum gas venting pressure of LFP batteries with a round safety valve is 3320 Pa,which is one order of magnitude higher than other batteries with oval or cavity safety valve;(Ⅱ)the LFP battery with oval safety valve has the lowest TR hazard as shown by the TR hazard assessment model based on gray-fuzzy analytic hierarchy process.This study reveals the effect of safety valve type on TR and gas venting,providing a clear direction for the safety valve design.展开更多
In an experiment performed on the Shenguang-III prototype laser facility, collective Thomson scattering (TS) is used to study the spatialgrowth of stimulated Brillouin scattering (SBS) in a gas-filled hohlraum by dete...In an experiment performed on the Shenguang-III prototype laser facility, collective Thomson scattering (TS) is used to study the spatialgrowth of stimulated Brillouin scattering (SBS) in a gas-filled hohlraum by detecting the SBS-driven ion acoustic wave. High-quality timeresolved SBS and TS spectra are obtained simultaneously in the experiment, and these are analyzed by a steady-state code based on theray-tracing model. The analysis indicates that ion–ion collisions may play an important role in suppressing SBS growth in the Au plasma;as aresult, the SBS excited in the filled gas region is dominant. In the early phase of the laser pulse, SBS originates primarily from the high-densityplasma at the edges of the interaction beam channel, which is piled up by the heating of the interaction beam. Throughout the duration of thelaser pulse, the presence of the TS probe beam might mitigate SBS by perturbing the density distribution around the region overlapping withthe interaction beam.展开更多
The ultrahigh specific energy density and low cost of lithium-sulfur batteries are suitable for the next generation of energy storage.However,the shuttle issue and sluggish conversion kinetics of polysulfides remain u...The ultrahigh specific energy density and low cost of lithium-sulfur batteries are suitable for the next generation of energy storage.However,the shuttle issue and sluggish conversion kinetics of polysulfides remain unsolved.Confining metal nanoclusters with strong polarity in conductive porous carbon is an effective strategy for tackling such knotty issues.Herein,we design and synthesize hollow cubic carbon embedded with highly dispersed cobalt nanoclusters as an effective sulfur reservoir for lithium sulfur batteries.The large cavity structure and well-dispersed cobalt nanoclusters,with uniform sizes near 11 nm,enable the hosting structure to hold the high sulfur loading,70%capacity retention after 500 cycles at 2 C with a high sulfur loading of 6.5 mg·cm^(−2),effective stress release,accelerated polysulfide conversion,superior rate performance,strong physical confinement and chemical absorption capability.Further density functional theoretical calculations demonstrate that the welldispersed cobalt nanoclusters in the hosting structure play a critical electrocatalytic role in boosting the capability of absorbing and converting polysulfides.展开更多
Phosphorene,especially black phosphorus(BP),has attracted considerable attention due to the unique characteristics,such as tunable direct bandgap,high carrier mobility,and strong in-plane anisotropy.Recently,a new mod...Phosphorene,especially black phosphorus(BP),has attracted considerable attention due to the unique characteristics,such as tunable direct bandgap,high carrier mobility,and strong in-plane anisotropy.Recently,a new modification strategy for black phosphorus has been developed by alloying black phosphorus with the congener element arsenic.The elemental composition tuning of black phosphorus with arsenic can not only maintain its special crystal structure and high anisotropy but also modify its electrical and optical properties for the further applications of multifunctional devices.The achieved two-dimensional(2D)black arsenic-phosphorus materials exhibit outstanding optical,electrical,and photoelectric properties,such as very narrow band gap,anisotropic infrared absorption,and bipolar transfer characteristics,presenting great potential in infrared photodetectors and highperformance field effect transistors(FETs).In this review,we introduce the recent progress made in the synthesis and applications of black arsenic-phosphorus,and provide an outlook and perspectives on the current challenges and future opportunities in this field.We hope that this review can bring new insights and inspirations on the further development of 2D black arsenic-phosphorus based materials and devices.展开更多
基金The authors acknowledge the insightful suggestions and comments from Dr. S. C. Zhang and N. N. Mao at Peking University. This work was supported by the National Natural Science Foundation of China （Nos. 51502167 and 21473110）, and the fundamental Research Funds for the Central Universities （No. GK201502003）, L. Z. and J. K. acknowledge the funding by the Center for Integrated Quantum Materials under NSF （No. DMR-1231319）.
文摘The anisotropic two-dimensional （2D） layered material rhenium disulfide （ReSe2） has attracted considerable attention because of its unusual properties and promising applications in electronic and optoelectronic devices. However, because of its low lattice symmetry and interlayer decoupling, anisotropic growth and out-of-plane growth occur easily, yielding thick flakes, dendritic structure, or flower-like structure. In this stud34 we demonstrated a bottom-up method for the controlled and scalable synthesis of ReSe2 by van der Waals epitaxy. To achieve controllable growth, a micro-reactor with a confined reaction space was constructed by stacking two mica substrates in the chemical vapor deposition system. Within the confined reaction space, the nucleation density and growth rate of ReSe2 were significantly reduced, favoring the large-area synthesis of ReSe2 with a uniform monolayer thickness. The morphological evolution of ReSe2 with growth temperature indicated that the anisotropic growth was suppressed at a low growth temperature （〈600 ℃）. Field-effect transistors employing the grown ReSe2 exhibited p-type conduction with a current ON/OFF ratio up to 10s and a hole carrier mobility of 0.98 cm^2/（V·s）. Furthermore, the ReSe2 device exhibited an outstanding photoresponse to near-infrared light, with responsivity up to 8.4 and 5.1 A/W for 850- and 940-nm light, respectively. This work not only promotes the large-scale application of ReSe2 in high-performance electronic devices but also clarifies the growth mechanism of low-lattice symmetry 2D materials.
基金the National Key R&D Program of China(No.2017YFA0208200)the National Natural Science Foundation of China(Nos.22022505,21872069,and 22109069)+3 种基金the Fundamental Research Funds for the Central Universities of China(Nos.020514380266,020514380272,and 020514380274)the Scientific and Technological Innovation Special Fund for Carbon Peak and Carbon Neutrality of Jiangsu Province(BK20220008)the Nanjing International Collaboration Research Program(Nos.202201007 and 2022SX00000955)the Suzhou Gusu Leading Talent Program of Science and Technology Innovation and Entrepreneurship in Wujiang District(No.ZXL2021273).
文摘Organic–inorganic metal halide perovskites have attained extensive attention owing to their outstanding photovoltaic performances,but the existence of numerous defects in crystalline perovskites is still a serious constraint for the further development of perovskite solar cells(PSCs).In particular,the rapid crystallization guided by anti-solvents leads to plenty of surficial and interfacial defects in perovskite films.Herein,we report the adoption of a pseudo-halide anion based ionic liquid additive,1-butyl-3-methylimidazolium thiocyanate(BMIMSCN)for growing ternary cation(CsFAMA,where FA=formamidinium and MA=methylammonium)perovskites with large-scale crystal grains and strong preferential orientation via the enhanced Ostwald ripening.Meanwhile,a novel halide-free passivator,benzylammonium formate(BAFa),was employed as a buffering layer on the perovskite films to suppress surface-dominated charge recombination.As a result,the cooperative effects of BMIMSCN additive and BAFa passivator lead to significant enhancements on fluorescence lifetime(from 79.41 to 201.01 ns),open-circuit voltage(from 1.13 to 1.19 V),photoelectric conversion efficiency(from 18.90%to 22.33%).Moreover,the BMIMSCN/BAFa-CsFAMA PSCs demonstrated greatly improved stability against moisture and heat.This work suggests a promising strategy to improve the quality of perovskite materials via reducing the surficial and interfacial defects by the synergistic effects of lattice doping and interface engineering.
基金supported by the National Key R&D Program of China(No.2021YFB2402001)the Postgraduate Innovation and Entrepreneurship Practice Project of Anhui Province(No.2022cxcysj013)+2 种基金the China Postdoctoral Science Foundation(No.2022T150615)the Fundamental Research Funds for the Central Universities(No.WK5290000002)supported by Youth Innovation Promotion Association CAS(No.Y201768)。
文摘The safety valve is an important component to ensure the safe operation of lithium-ion batteries(LIBs).However,the effect of safety valve type on the thermal runaway(TR)and gas venting behavior of LIBs,as well as the TR hazard severity of LIBs,are not known.In this paper,the TR and gas venting behavior of three 100 A h lithium iron phosphate(LFP)batteries with different safety valves are investigated under overheating.Compared to previous studies,the main contribution of this work is in studying and evaluating the effect of gas venting behavior and TR hazard severity of LFP batteries with three safety valve types.Two significant results are obtained:(Ⅰ)the safety valve type dominates over gas venting pressure of battery during safety venting,the maximum gas venting pressure of LFP batteries with a round safety valve is 3320 Pa,which is one order of magnitude higher than other batteries with oval or cavity safety valve;(Ⅱ)the LFP battery with oval safety valve has the lowest TR hazard as shown by the TR hazard assessment model based on gray-fuzzy analytic hierarchy process.This study reveals the effect of safety valve type on TR and gas venting,providing a clear direction for the safety valve design.
基金supported by the Natural Science Foundation of China(Grant Nos.11905204,11975215,12105270,12205272,12205274,12275032,12275251,and 12035002)the Laser Fusion Research Center Funds for Young Talents(Grant No.RCFPD3-2019-6).
文摘In an experiment performed on the Shenguang-III prototype laser facility, collective Thomson scattering (TS) is used to study the spatialgrowth of stimulated Brillouin scattering (SBS) in a gas-filled hohlraum by detecting the SBS-driven ion acoustic wave. High-quality timeresolved SBS and TS spectra are obtained simultaneously in the experiment, and these are analyzed by a steady-state code based on theray-tracing model. The analysis indicates that ion–ion collisions may play an important role in suppressing SBS growth in the Au plasma;as aresult, the SBS excited in the filled gas region is dominant. In the early phase of the laser pulse, SBS originates primarily from the high-densityplasma at the edges of the interaction beam channel, which is piled up by the heating of the interaction beam. Throughout the duration of thelaser pulse, the presence of the TS probe beam might mitigate SBS by perturbing the density distribution around the region overlapping withthe interaction beam.
基金supported by the National Key Research and Development Program of China(No.2017YFA0208200)the Fundamental Research Funds for the Central Universities of China(No.0205-14380219)+3 种基金the National Natural Science Foundation of China(Nos.22109069,22022505,21872069,21802119,and 21808195)the Natural Science Foundation of Jiangsu Province(Nos.BK20181056 and BK20180008)the Funding For School-Level Research Projects of Yancheng Institute of Technology(Nos.xjr2019006,and xjr2019055)the 2021 Suzhou Gusu Leading Talents of Science and Technology Innovation and Entrepreneurship in Wujiang District,the Open Fund of Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province and some enterprise projects(Nos.WJGTT-XT3,19KJA540001,and JNHB068).
文摘The ultrahigh specific energy density and low cost of lithium-sulfur batteries are suitable for the next generation of energy storage.However,the shuttle issue and sluggish conversion kinetics of polysulfides remain unsolved.Confining metal nanoclusters with strong polarity in conductive porous carbon is an effective strategy for tackling such knotty issues.Herein,we design and synthesize hollow cubic carbon embedded with highly dispersed cobalt nanoclusters as an effective sulfur reservoir for lithium sulfur batteries.The large cavity structure and well-dispersed cobalt nanoclusters,with uniform sizes near 11 nm,enable the hosting structure to hold the high sulfur loading,70%capacity retention after 500 cycles at 2 C with a high sulfur loading of 6.5 mg·cm^(−2),effective stress release,accelerated polysulfide conversion,superior rate performance,strong physical confinement and chemical absorption capability.Further density functional theoretical calculations demonstrate that the welldispersed cobalt nanoclusters in the hosting structure play a critical electrocatalytic role in boosting the capability of absorbing and converting polysulfides.
基金This work was supported by the National Key Research and Development Program of China(No.2017YFA0208200)the Fundamental Research Funds for the Central Universities of China(No.0205–14380266)+3 种基金the National Natural Science Foundation of China(Nos.22022505,21872069,and 22109069)the Natural Science Foundation of Jiangsu Province(No.BK20180008)the Doctoral Innovation and Entrepreneurship Program of Jiangsu Province(No.JSSCBS20210045)the Shenzhen Fundamental Research Program of Science,Technology and Innovation Commission of Shenzhen Municipality(No.JCYJ20180307155007589).
文摘Phosphorene,especially black phosphorus(BP),has attracted considerable attention due to the unique characteristics,such as tunable direct bandgap,high carrier mobility,and strong in-plane anisotropy.Recently,a new modification strategy for black phosphorus has been developed by alloying black phosphorus with the congener element arsenic.The elemental composition tuning of black phosphorus with arsenic can not only maintain its special crystal structure and high anisotropy but also modify its electrical and optical properties for the further applications of multifunctional devices.The achieved two-dimensional(2D)black arsenic-phosphorus materials exhibit outstanding optical,electrical,and photoelectric properties,such as very narrow band gap,anisotropic infrared absorption,and bipolar transfer characteristics,presenting great potential in infrared photodetectors and highperformance field effect transistors(FETs).In this review,we introduce the recent progress made in the synthesis and applications of black arsenic-phosphorus,and provide an outlook and perspectives on the current challenges and future opportunities in this field.We hope that this review can bring new insights and inspirations on the further development of 2D black arsenic-phosphorus based materials and devices.
