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Textured Asymmetric Membrane Electrode Assemblies of Piezoelectric Phosphorene and Ti_(3)C_(2)T_(x)MXene Heterostructures for Enhanced Electrochemical Stability and Kinetics in LIBs
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作者 Yihui Li Juan Xie +10 位作者 Ruofei Wang Shugang Min Zewen Xu Yangjian Ding Pengcheng Su Xingmin Zhang Liyu Wei Jing‑Feng Li Zhaoqiang Chu jingyu sun Cheng Huang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第4期394-414,共21页
Black phosphorus with a superior theoretical capacity(2596 mAh g^(-1))and high conductivity is regarded as one of the powerful candidates for lithium-ion battery(LIB)anode materials,whereas the severe volume expansion... Black phosphorus with a superior theoretical capacity(2596 mAh g^(-1))and high conductivity is regarded as one of the powerful candidates for lithium-ion battery(LIB)anode materials,whereas the severe volume expansion and sluggish kinetics still impede its applications in LIBs.By contrast,the exfoliated two-dimensional phosphorene owns negligible volume variation,and its intrinsic piezoelectricity is considered to be beneficial to the Li-ion transfer kinetics,while its positive influence has not been discussed yet.Herein,a phosphorene/MXene heterostructure-textured nanopiezocomposite is proposed with even phosphorene distribution and enhanced piezo-electrochemical coupling as an applicable free-standing asymmetric membrane electrode beyond the skin effect for enhanced Li-ion storage.The experimental and simulation analysis reveals that the embedded phosphorene nanosheets not only provide abundant active sites for Li-ions,but also endow the nanocomposite with favorable piezoelectricity,thus promoting the Li-ion transfer kinetics by generating the piezoelectric field serving as an extra accelerator.By waltzing with the MXene framework,the optimized electrode exhibits enhanced kinetics and stability,achieving stable cycling performances for 1,000 cycles at 2 A g^(-1),and delivering a high reversible capacity of 524 m Ah g^(-1)at-20℃,indicating the positive influence of the structural merits of self-assembled nanopiezocomposites on promoting stability and kinetics. 展开更多
关键词 Phosphorene Nanopiezocomposite Piezo-electrochemical coupling Membrane electrode assembly Lithium-ion storage
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Insight into demand-driven preparation of single-atomic mediators for lithium–sulfur batteries
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作者 Miaoyu Lu Yifan Ding +3 位作者 Zaikun Xue Ziang Chen Yuhan Zou jingyu sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期205-219,I0007,共16页
Lithium-sulfur(Li-S) batteries have attracted considerable attention as one of the most appealing energy storage systems.Strenuous efforts have been devoted to tackling the tremendous challenges,mainly pertaining to t... Lithium-sulfur(Li-S) batteries have attracted considerable attention as one of the most appealing energy storage systems.Strenuous efforts have been devoted to tackling the tremendous challenges,mainly pertaining to the severe shuttle effect,sluggish redox kinetics and lithium dendritic growth.Single-atomic mediators as promising candidates exhibit impressive performance in addressing these intractable issues.Related research often utilizes a trial-and-error approach,proposing solutions to fabricate single-atomic materials with diversified features.However,comprehensive review articles especially targeting demand-driven preparation are still in a nascent stage.Inspired by these considerations,this review summarizes the design of single-atomic mediators based on the application case-studies in LiS batteries and other metal-sulfur systems.Emerging preparation routes represented by chemical vapor deposition technology are introduced in a demand-oriented classification.Finally,future research directions are proposed to foster the advancement of single-atomic mediators in Li-S realm. 展开更多
关键词 Single-atom catalyst Lithium–sulfur battery Chemical vapor deposition Demand-driven preparation
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气相助剂辅助绝缘衬底上石墨烯生长:现状与展望
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作者 刘若娟 刘冰之 +1 位作者 孙靖宇 刘忠范 《物理化学学报》 SCIE CAS CSCD 北大核心 2023年第1期29-40,共12页
借助化学气相沉积(chemical vapor deposition,CVD)技术在绝缘衬底上直接生长的石墨烯薄膜,在能源存储/转换等领域有着广阔的应用前景。然而,绝缘衬底表面石墨烯的生长呈现成核密度高、畴区尺寸小、生长速率低等特点,获得的石墨烯薄膜... 借助化学气相沉积(chemical vapor deposition,CVD)技术在绝缘衬底上直接生长的石墨烯薄膜,在能源存储/转换等领域有着广阔的应用前景。然而,绝缘衬底表面石墨烯的生长呈现成核密度高、畴区尺寸小、生长速率低等特点,获得的石墨烯薄膜往往具有较高的晶界密度和较低的层数均匀度,严重制约着石墨烯基器件性能的发挥。在反应体系中引入气相助剂可有效降低碳源裂解和石墨烯生长的能垒,从而实现石墨烯品质与生长速率的提升。本文综述气相助剂辅助绝缘衬底上石墨烯制备的方法:首先对绝缘衬底上石墨烯的生长行为进行分析;随后着重介绍几类常见的气相助剂辅助石墨烯生长的策略和机理;最后,总结绝缘衬底上制备高品质石墨烯存在的挑战,并对未来的发展方向进行展望。 展开更多
关键词 石墨烯 化学气相沉积 绝缘衬底 气相助剂
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Tuning dual-atom mediator toward high-rate bidirectional polysulfide conversion in Li-S batteries
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作者 Yifan Ding Zhongti sun +8 位作者 Jianghua Wu Tianran Yan Lin Shen Zixiong Shi Yuhan Wu Xiaoqing Pan Liang Zhang Qiang Zhang jingyu sun 《Journal of Energy Chemistry》 SCIE EI CSCD 2023年第12期462-472,I0012,共12页
An emerging practice in the realm of Li-S batteries lies in the employment of single-atom catalysts(SACs)as effective mediators to promote polysulfide conversion,but monometallic SACs affording isolated geometric disp... An emerging practice in the realm of Li-S batteries lies in the employment of single-atom catalysts(SACs)as effective mediators to promote polysulfide conversion,but monometallic SACs affording isolated geometric dispersion and sole electronic configuration limit the catalytic benefits and curtail the cell performance.Here,we propose a class of dual-atom catalytic moieties comprising hetero-or homo-atomic pairs anchored on N-doped graphene(NG)to unlock the liquid–solid redox puzzle of sulfur,readily realizing Li-S full cell under high-rate-charging conditions.As for Fe-Ni-NG,in-depth experimental and theoretical analysis reveal that the hetero-atomic orbital coupling leads to altered energy levels,unique electronic structures,and varied Fe oxidation states in comparison with homo-atomic structures(FeFe-NG or Ni-Ni-NG).This would weaken the bonding energy of polysulfide intermediates and thus enable facile electrochemical kinetics to gain rapid liquid-solid Li_(2)S_(4)?Li_(2)S conversion.Encouragingly,a Li-S battery based on the S@Fe-Ni-NG cathode demonstrates unprecedented fast-charging capability,documenting impressive rate performance(542.7 mA h g^(-1)at 10.0 C)and favorable cyclic stability(a capacity decay of 0.016%per cycle over 3000 cycles at 10.0 C).This finding offers insights to the rational design and application of dual-atom mediators for Li-S batteries. 展开更多
关键词 Li-S batteries Reaction kinetics Dual-atom Rate-determining step High-rate performance
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石墨烯晶圆的制备:从高品质到规模化 被引量:2
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作者 姜蓓 孙靖宇 刘忠范 《物理化学学报》 SCIE CAS CSCD 北大核心 2022年第2期3-15,共13页
石墨烯晶圆是引领未来的战略材料,在集成电路、微机电系统和传感器等领域具有广阔的应用前景。实现石墨烯晶圆广泛应用的前提是高品质材料的规模化制备。可控性高、工艺兼容性强、成本低的化学气相沉积(chemical vapor deposition,CVD)... 石墨烯晶圆是引领未来的战略材料,在集成电路、微机电系统和传感器等领域具有广阔的应用前景。实现石墨烯晶圆广泛应用的前提是高品质材料的规模化制备。可控性高、工艺兼容性强、成本低的化学气相沉积(chemical vapor deposition,CVD)法,是高品质石墨烯晶圆规模化制备的首选方法。本文将综述石墨烯晶圆的CVD制备进展:首先探讨石墨烯晶圆的制备需求,从实用牵引和应用场景出发,提出石墨烯晶圆的制备品质等级;随后重点介绍石墨烯的晶圆级制备方法和石墨烯晶圆材料的规模化制备技术;最后,对石墨烯晶圆可行的制备路线进行总结,并展望未来可能的发展方向。 展开更多
关键词 石墨烯晶圆 化学气相沉积 高品质 规模化制备
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Designing N-doped graphene/ReSe_(2)/Ti_(3)C_(2) MXene heterostructure frameworks as promising anodes for high-rate potassium-ion batteries 被引量:10
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作者 Zhou Xia Xiwen Chen +7 位作者 Haina Cia Zhaodi Fan Yuyang Yi Wanjian Yin Nan Wei Jingsheng Cai Yanfeng Zhang jingyu sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第2期155-162,I0006,共9页
Developing high-performance anodes for potassium ion batteries(KIBs) is of paramount significance but remains challenging.In the normal sense,electrode materials are prepared by ubiquitous wet chemical routes,which ot... Developing high-performance anodes for potassium ion batteries(KIBs) is of paramount significance but remains challenging.In the normal sense,electrode materials are prepared by ubiquitous wet chemical routes,which otherwise might not be versatile enough to create desired heterostructures and/or form clean interfacial areas for fast transport of K-ions and electrons.Along this line,rate capability/cycling stability of resulting KIBs are greatly handicapped.Herein we present an all-chemical vapor deposition approach to harness the direct synthesis of nitrogen-doped graphene(NG)/rhenium diselenide(ReSe_2)hybrids over three-dimensional MXene supports as superior heterostructure anode material for KIBs.In such an innovative design,1 T'-ReSe2 nanoparticles are sandwiched in between the NG coatings and MXene frameworks via strong interfacial interactions,thereby affording facile K~+ diffusion,enhancing overall conductivity,boosting high-power performance and reinforcing structural stability of electrodes.Thus-constructed anode delivers an excellent rate performance of 138 mAh g^(-1) at 10.0 A g^(-1) and a high reversible capacity of 90 mAh g^(-1) at 5 A g^(-1) after 300 cycles.Furthermore,the potassium storage mechanism has been systematically probed by advanced in situlex situ characterization techniques in combination with first principles computations. 展开更多
关键词 K-ion batteries High-rate ReSe_(2) N-doped graphene HETEROSTRUCTURE
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Bio-templated formation of defect-abundant VS2 as a bifunctional material toward high-performance hydrogen evolution reactions and lithium-sulfur batteries 被引量:4
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作者 Tianqi Guo Yingze Song +7 位作者 Zhongti sun Yuhan Wu Yu Xia Yayun Li Jianhui sun Kai Jiang Shixue Dou jingyu sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第3期34-42,共9页
Transition metal chalcogenides have nowadays garnered burgeoning interest owing to their fascinating electronic and catalytic properties,thus possessing great implications for energy conversion and storage application... Transition metal chalcogenides have nowadays garnered burgeoning interest owing to their fascinating electronic and catalytic properties,thus possessing great implications for energy conversion and storage applications.In this regard,their controllable synthesis in a large scale at low cost has readily become a focus of research.Herein we report diatomite-template generic and scalable production of VS2 and other transition metal sulfides targeting emerging energy conversion and storage applications.The conformal growth of VS2over diatomite template would endow them with defect-abundant features.Throughout detailed experimental investigation in combination with theoretical simulation,we reveal that the enriched active sites/sulfur vacancies of thus-derived VS2 architectures would pose positive impacts on the catalytic performance such in electrocatalytic hydrogen evolution reactions.We further show that the favorable electrical conductivity and highly exposed sites of VS2 hold promise for serving as sulfur host in the realm of Li-S batteries.Our work offers new insights into the templated and customized synthesis of defect-rich sulfides in a scalable fashion to benefit multifunctional energy applications. 展开更多
关键词 Bio-templated VANADIUM DISULFIDE Defect-abundant Hydrogen evolution reaction Lithium-sulfur BATTERIES
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3D Printing of NiCoP/Ti3C2 MXene Architectures for Energy Storage Devices with High Areal and Volumetric Energy Density 被引量:4
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作者 Lianghao Yu Weiping Li +3 位作者 Chaohui Wei Qifeng Yang Yuanlong Shao jingyu sun 《Nano-Micro Letters》 SCIE EI CAS CSCD 2020年第10期300-312,共13页
Designing high-performance electrodes via 3D printing for advanced energy storage is appealing but remains challenging.In normal cases,light-weight carbonaceous materials harnessing excellent electrical conductivity h... Designing high-performance electrodes via 3D printing for advanced energy storage is appealing but remains challenging.In normal cases,light-weight carbonaceous materials harnessing excellent electrical conductivity have served as electrode candidates.However,they struggle with undermined areal and volumetric energy density of supercapacitor devices,thereby greatly impeding the practical applications.Herein,we demonstrate the in situ coupling of NiCoP bimetallic phosphide and Ti3C2 MXene to build up heavy NCPM electrodes affording tunable mass loading throughout 3D printing technology.The resolution of prints reaches 50μm and the thickness of device electrodes is ca.4 mm.Thus-printed electrode possessing robust open framework synergizes favorable capacitance of NiCoP and excellent conductivity of MXene,readily achieving a high areal and volumetric capacitance of 20 F cm^-2 and 137 F cm^-3 even at a high mass loading of^46.3 mg cm^-2.Accordingly,an asymmetric supercapacitor full cell assembled with 3D-printed NCPM as a positive electrode and 3D-printed activated carbon as a negative electrode harvests remarkable areal and volumetric energy density of 0.89 mWh cm^-2 and 2.2 mWh cm^-3,outperforming the most of state-of-the-art carbon-based supercapacitors.The present work is anticipated to offer a viable solution toward the customized construction of multifunctional architectures via 3D printing for high-energy-density energy storage systems. 展开更多
关键词 3D printing NiCoP/MXene Asymmetric supercapacitor Energy density Tailorable loading
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Confining TiO_2 Nanotubes in PECVD-Enabled Graphene Capsules Toward Ultrafast K-Ion Storage: In Situ TEM/XRD Study and DFT Analysis 被引量:3
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作者 Jingsheng Cai Ran Cai +7 位作者 Zhongti sun Xiangguo Wang Nan Wei Feng Xu Yuanlong Shao Peng Gao Shixue Dou jingyu sun 《Nano-Micro Letters》 SCIE EI CAS CSCD 2020年第9期310-323,共14页
Titanium dioxide(TiO2) has gained burgeoning attention for potassium-ion storage because of its large theoretical capacity,wide availability,and environmental benignity.Nevertheless,the inherently poor conductivity gi... Titanium dioxide(TiO2) has gained burgeoning attention for potassium-ion storage because of its large theoretical capacity,wide availability,and environmental benignity.Nevertheless,the inherently poor conductivity gives rise to its sluggish reaction kinetics and inferior rate capability.Here,we report the direct graphene growth over TiO2 nanotubes by virtue of chemical vapor deposition.Such conformal graphene coatings effectively enhance the conductive environment and well accommodate the volume change of TiO2 upon potassiation/depotassiation.When paired with an activated carbon cathode,the graphene-armored TiO2 nanotubes allow the potassium-ion hybrid capacitor full cells to harvest an energy/power density of 81.2 Wh kg-1/3746.6 W kg-1.We further employ in situ transmis sion electron microscopy and ope rando X-ray diffraction to probe the potassium-ion storage behavior.This work offers a viable and versatile solution to the anode design and in situ probing of potassium storage technologies that is readily promising for practical applications. 展开更多
关键词 TiO2 Potassium storage In situ TEM Plasma-enhanced CVD GRAPHENE
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Direct insight into sulfiphilicity-lithiophilicity design of bifunctional heteroatom-doped graphene mediator toward durable Li-S batteries 被引量:2
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作者 Haina Ci Menglei Wang +6 位作者 Zhongti sun Chaohui Wei Jingsheng Cai Chen Lu Guang Cui Zhongfan Liu jingyu sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第3期474-482,I0013,共10页
The practical applications of lithium-sulfur(Li-S)battery have been greatly hindered by the severe polysulfide shuttle at the cathode and rampant lithium dendrite growth at the anode.One of the effective solutions dea... The practical applications of lithium-sulfur(Li-S)battery have been greatly hindered by the severe polysulfide shuttle at the cathode and rampant lithium dendrite growth at the anode.One of the effective solutions deals with concurrent management of both electrodes.Nevertheless,this direction remains in a nascent stage due to a lack of material selection and mechanism exploration.Herein,we devise a temperature-mediated direct chemical vapor deposition strategy to realize the controllable synthesis of three-dimensional boron/nitrogen dual-doped graphene(BNG)particulated architectures,which is employed as a light-weighted and multi-functional mediator for both electrodes in Li-S batteries.Benefiting from the“sulfiphilic”and“lithiophilic”features,the BNG modified separator not only enables boosted kinetics of polysulfide transformation to mitigate the shuttle effect but also endows uniform lithium deposition to suppress the dendritic growth.Theoretical calculations in combination with electro-kinetic tests and operando Raman analysis further elucidate the favorable sulfur and lithium electrochemistry of BNG at a molecular level.This work offers direct insight into the mediator design via controllable synthesis of graphene materials to tackle the fundamental challenges of Li-S batteries. 展开更多
关键词 Li-S batteries B/N dual-doped graphene MEDIATOR Shuttle effect Lithium dendrite
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Non-precious metal electrocatalysts for two-electron oxygen electrochemistry: Mechanisms, progress, and outlooks 被引量:1
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作者 Yuhan Wu Jianhui sun +1 位作者 Shixue Dou jingyu sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第6期54-69,I0003,共17页
Hydrogen peroxide (H_(2)O_(2)) is a valuable chemical for a wide variety of applications. The environmentally friendly production route of the electrochemical reduction of O_(2)to H_(2)O_(2) has become an attractive a... Hydrogen peroxide (H_(2)O_(2)) is a valuable chemical for a wide variety of applications. The environmentally friendly production route of the electrochemical reduction of O_(2)to H_(2)O_(2) has become an attractive alternative to the traditional anthraquinone process. The efficiency of electrosynthesis process depends considerably on the availability of cost-effective catalysts with high selectivity, activity, and stability.Currently, there are many outstanding issues in the preparation of highly selective catalysts, the exploration of the interface electrolysis environment, and the construction of electrolysis devices, which have led to extensive research efforts. Distinct from the existing few comprehensive review articles on H_(2)O_(2) production by two-electron oxygen reduction, the present review first explains the principle of the oxygen reduction reaction and then highlights recent advances in the regulation and control strategies of different types of catalysts. Key factors of electrode structure and device design are discussed. In addition,we highlight the promising co-production combination of this system with renewable energy or energy storage systems. This review can help introduce the potential of oxygen reduction electrochemical production of high-flux H_(2)O_(2) to the commercial market. 展开更多
关键词 2e-ORR(oxygen reduction reaction) H_(2)O_(2) Heteroatom doping Single atom Carbon-based catalyst
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Biomass Template Derived Boron/Oxygen Co-Doped Carbon Particles as Advanced Anodes for Potassium-Ion Batteries 被引量:1
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作者 Xueyu Lian Zhongti sun +4 位作者 Qingqing Mei Yuyang Yi Junhua Zhou Mark H.Rummeli jingyu sun 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2022年第1期344-352,共9页
Among various anode candidates for potassium-ion batteries,carbonaceous materials have attracted significant attention due to their overwhelming advantages including cost-effectiveness and environmental benignity.Howe... Among various anode candidates for potassium-ion batteries,carbonaceous materials have attracted significant attention due to their overwhelming advantages including cost-effectiveness and environmental benignity.However,the inferior specific capacity and the sluggish reaction kinetics hinder the further development in this realm.Herein,we report biomass templated synthesis of boron/oxygen heteroatom co-doped carbon particles(BO-CPs)via direct plasma-enhanced chemical vapor deposition.With the combined advantages of abundant active sites,large accessible surface area,and functional groups,BO-CP anode exhibits high reversible specific capacity(426.5 mAh g^(-1)at 0.1 A g^(-1))and excellent rate performance(166.5 mAh g^(-1)at 5 A g^(-1)).The K-ion storage mechanism is probed by operando Raman spectroscopy,ex situ X-ray photoelectron spectroscopy/electrochemical impedance spectroscopy,galvanostatic intermittent titration technique measurements,and theoretical simulations.The synergistic effect of boron and oxygen co-doping greatly facilitates the performance of carbon-based anode,wherein boron dopant improves the conductivity of carbon framework and the oxygen dopant affords ample active sites and thus harvests additional specific capacity.This work is anticipated to propel the development of high-performance anode materials for emerging energy storage devices. 展开更多
关键词 ANODE B/O co-doping carbon high capacity potassium-ion batteries
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A Natural Polymer Captor for Immobilizing Polysulfide/Polyselenide in Working Li-SeS_(2) Batteries
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作者 Yin Zhang Menglei Wang +9 位作者 Yi Guo Lingzhi Huang Boya Wang Yunhong Wei Peng Jing Yueying Zhang Yun Zhang Qian Wang jingyu sun Hao Wu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第7期55-73,共19页
SeS_(2) has become a promising cathode material owing to its enhanced electrical conductivity over sulfur and higher theoretical specific capacity than selenium;however,the working Li-SeS_(2) batteries have to face th... SeS_(2) has become a promising cathode material owing to its enhanced electrical conductivity over sulfur and higher theoretical specific capacity than selenium;however,the working Li-SeS_(2) batteries have to face the practical challenges from the severe shuttling of soluble dual intermediates of polysulfide and polyselenide,especially in high-SeS_(2)-loading cathodes.Herein,a natural organic polymer,Nicandra physaloides pectin(NPP),is proposed to serve as an effective polysulfide/polyselenide captor to address the shuttling issues.Informed by theoretical calculations,NPP is competent to provide a Lewis base-based strong binding interaction with polysulfides/polyselenides via forming lithium bonds,and it can be homogeneously deposited onto a three-dimensional double-carbon conductive scaffold to finally constitute a polysulfide/polyselenide-immobilizing interlayer.Operando spectroscopy analysis validates the enhanced polysulfide/polyselenide trapping and high conversion efficiency on the constructed interlayer,hence bestowing the Li-SeS_(2) cells with ultrahigh rate capability(448 mAh g^(−1)at 10 A g^(−1)),durable cycling lifespan(≈0.037%capacity attenuation rate per cycle),and high areal capacity(>6.5 mAh cm^(−2))at high SeS_(2) loading of 15.4 mg cm^(−2).Importantly,pouch cells assembled with this interlayer exhibit excellent flexibility,decent rate capability with relatively low electrolyte-to-capacity ratio,and stable cycling life even under a low electrolyte condition,promising a low-cost,viable design protocol toward practical Li-SeS_(2) batteries. 展开更多
关键词 Li-SeS_(2)batteries Nicandra physaloides pectin Interlayer Shuttle effect Pouch cells
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Ultrafast proton transfer dynamics of 2-(2'-hydroxyphenyl)benzoxazole dye in different solvents
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作者 孙四梅 张嵩 +4 位作者 宋娇 郭小珊 江超 孙静俞 王赛玉 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第2期606-612,共7页
The excited-state intramolecular proton transfer of 2-(2-hydroxyphenyl)benzoxazole dye in different solvents is investigated using ultrafast femtosecond transient absorption spectroscopy combined with quantum chemical... The excited-state intramolecular proton transfer of 2-(2-hydroxyphenyl)benzoxazole dye in different solvents is investigated using ultrafast femtosecond transient absorption spectroscopy combined with quantum chemical calculations.Conformational conversion from the syn-enol configuration to the keto configuration is proposed as the mechanism of excited-state intramolecular proton transfer.The duration of excited-state intramolecular proton transfer is measured to range from 50 fs to 200 fs in different solvents.This time is strongly dependent on the calculated energy gap between the N-S;and T-S;structures in the S;state.Along the proton transfer reaction coordinate,the vibrational relaxation process on the S;state potential surface is observed.The duration of the vibrational relaxation process is determined to be from8.7 ps to 35 ps dependent on the excess vibrational energy. 展开更多
关键词 proton transfer vibrational relaxation femtosecond transient absorption spectroscopy quantum chemical calculations
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Distributive characteristics of projection from vestibular nuclei to nucleus raphe magnus in rats
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作者 jingyu sun Yulin Dong +2 位作者 Fuxing Zhang Jianhua Qiu Yunqing Li 《Neural Regeneration Research》 SCIE CAS CSCD 2007年第5期262-266,共5页
BACKGROUND: Morphological studies have confirmed that vestibular nuclei accepts serotoninergic projections from nucleus raphe magnus, nucleus raphes pallidus, etc. But it is still unclear whether there is bi-directio... BACKGROUND: Morphological studies have confirmed that vestibular nuclei accepts serotoninergic projections from nucleus raphe magnus, nucleus raphes pallidus, etc. But it is still unclear whether there is bi-directional association between vestibular nuclei and nucleus raphe magnus. OBJECTIVE: To observe the characteristics of projective fibers from vestibular nuclei to nucleus raphe magnus using tetramethyl rhodamine (TMR) in rats, so as to provide more sufficient morphological evidence of neural association from vestibular nuclei. DESIGN: An observational experiment. SETTING: Department of Anatomy (K.K. Leung Brain Research Center), the Fourth Military Medical University of Chinese PLA. MATERIALS: Eighteen male SD rats of clean degree, weighing 250-280 g, were provided by the Experimental Animal Center of the Fourth Military Medical University of Chinese PLA. METHODS: The experiments were carried out in the laboratory of Department of Anatomy (K.K. Leung Brain Research Center), the Fourth Military Medical University of Chinese PLA from September 2006 to January 2007. All the rats were anesthetized with intraperitoneal injection of pentobarbital sodium, then according to the coordinates on the rat brain atlas, 0.1 μL TMR (100 g/L) was injected into nucleus raphes magnus via the tip of glass microtubule by means of microinjection. Seven days later, the rats were anesthetized, then perfused and fixed to remove brain, and then frozen coronal brain sections were prepared. The retrogradely labeled neurons in the injected and projected sites were observed under fluorescence microscope. Light filters with evoked wave length of 540-553 nm and emission wave length ≥ 1 580 nm were selected to observe the orange TMR-labeled neurons. All the sections were observed and counted under the fluorescence microscope. MAIN OUTCOME MEASURES: Characteristics and number of retrogradely labeled neurons at different sites of nuclei. RESULTS: Totally 18 SD rats were enrolled, 9 of them were excluded due to the deviation of injected site, and the other 9 were involved in the final analysis of results. The concentrated region of TMR injection was mainly restricted to nucleus raphes magnus, and diffused to the surrounding area to different extents. There were obvious differences in the distributions of the labeled neurons among the subdivisions in vestibular nuclei, as well as the distributions of the labeled neurons at different sites in the same subdivision. The majority of the labeled neurons distributed in the rostral levels of medial vestibular nucleus and the lateral vestibular nucleus, while fewer labeled neurons were observed in superior vestibular nucleus. CONCLUSION: ① There might be bi-directional association between vestibular nucli and nucleus raphe magnus, suggesting that nucleus raphe magnus played a role in the transmission and processing of vestibular information. ② The projection from nucleus raphe magnus to vestibular nucleus has certain distributive characteristics in the region. 展开更多
关键词 vestibular nuclei nucleus raphe magnus RATS
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Transfer-free chemical vapor deposition graphene for nitride epitaxy: challenges, current status and future outlook
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作者 Xiang Gao Senlin Li +4 位作者 Jingfeng Bi Kaixuan Zhou Meng Li Zhongfan Liu jingyu sun 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第3期824-840,共17页
Graphene, a two-dimensional material with outstanding electrical and mechanical properties, has attracted considerable attention in the field of semiconductor technologies due to its potential use as a buffer layer fo... Graphene, a two-dimensional material with outstanding electrical and mechanical properties, has attracted considerable attention in the field of semiconductor technologies due to its potential use as a buffer layer for the epitaxial Ⅲ-nitride growth. In recent years, significant progress has been made in the chemical vapor deposition growth of graphene on various insulating substrates for the nitride epitaxy, which offers a facile, inexpensive, and easily scalable methodology. However, certain challenges are still present in the form of producing high-quality graphene and achieving optimal interface compatibility with Ⅲ-nitride materials.In this review, we provide an overview of the bottlenecks associated with the transferred graphene fabrication techniques and the state-of-the-art techniques for the transfer-free graphene growth. The present contribution highlights the current progress in the transfer-free graphene growth on different insulating substrates, including sapphire, quartz, SiO_(2)/Si, and discusses the potential applications of transfer-free graphene in the Ⅲ-nitride epitaxy. Finally, it includes the prospects of the transfer-free graphene growth for the Ⅲ-nitride epitaxy and the challenges that should be overcome to realize its full potential in this field. 展开更多
关键词 Transfer-free chemical vapor deposition graphene for nitride epitaxy challenges current status and future outlook GRAPHENE
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碳纳米管提升氧化亚硅负极稳定性的起源 被引量:2
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作者 周军华 王佳琪 +8 位作者 施启涛 连雪玉 刘玉 刘立军 Alicja Bachmatiuk 孙靖宇 杨瑞枝 Jin-Ho Choi Mark H.Rümmeli 《Science China Materials》 SCIE EI CAS CSCD 2023年第9期3461-3467,共7页
高容量的SiO (SO)合金基材料是最有希望的下一代锂离子电池负极之一.使用碳纳米管(CNTs)导电添加剂,虽然可以有效地解决SO较差的循环寿命这一难题,然而除了动力学因素之外,其它潜在的作用机理目前仍不明确.在本工作中,一系列的测试结果... 高容量的SiO (SO)合金基材料是最有希望的下一代锂离子电池负极之一.使用碳纳米管(CNTs)导电添加剂,虽然可以有效地解决SO较差的循环寿命这一难题,然而除了动力学因素之外,其它潜在的作用机理目前仍不明确.在本工作中,一系列的测试结果表明CNTs可以使电极在循环后依然维持完整的导电网络,确保均匀的电化学反应.CNTs也使得电极局部的体积膨胀得到了抑制,从而避免了固态电解质界面的不断生长,活性材料从集流体剥离,甚至析锂.得益于CNTs的上述作用, SO-CNTs负极在0.5 C (1 C=1600 mA g^(-1))下可以稳定循环200次,其容量保持率为96.2%. CNTs的作用机理也进一步地在商业化的SO/石墨复合负极(SO650-CNTs, 1 C=650 mA g^(-1))中得到了验证,SO650-CNTs在1 C下循环400次后容量保持率为80.6%.本工作为导电添加剂的作用机理提出了新的见解,并将有助于加速合金类负极的商业化进程. 展开更多
关键词 导电添加剂 固态电解质 电化学反应 动力学因素 活性材料 体积膨胀 硅负极 导电网络
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Carrier-free nanoprodrug for p53-mutated tumor therapy via concurrent delivery of zinc-manganese dual ions and ROS 被引量:1
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作者 Jinping Wang Chang Qu +6 位作者 Xinyue Shao Guoqiang Song jingyu sun Donghong Shi Ran Jia Hailong An Hongjun Wang 《Bioactive Materials》 SCIE CSCD 2023年第2期404-417,共14页
Human cancers typically express a high level of tumor-promoting mutant p53 protein(Mutp53)with a minimal level of tumor-suppressing wild-type p53 protein(WTp53).In this regard,inducing Mutp53 degradation while activat... Human cancers typically express a high level of tumor-promoting mutant p53 protein(Mutp53)with a minimal level of tumor-suppressing wild-type p53 protein(WTp53).In this regard,inducing Mutp53 degradation while activating WTp53 is a viable strategy for precise anti-tumor therapy.Herein,a new carrier-free nanoprodrug(i.e.,Mn-ZnO_(2)nanoparticles)was developed for concurrent delivery of dual Zn-Mn ions and reactive oxygen species(ROS)within tumor to regulate the p53 protein for high anti-tumor efficacy.In response to the mild tumor acidic environment,the released Zn^(2+)and H_(2)O_(2)from Mn-ZnO_(2)NPs induced ubiquitination-mediated proteasomal degradation of Mutp53,while the liberative Mn^(2+)and increased ROS level activated the ATM-p53-Bax pathway to elevate WTp53 level.Both in vitro and in vivo results demonstrated that pH-responsive decomposition of Mn-ZnO2 NPs could effectively elevate the intracellular dual Zn-Mn ions and ROS level and subsequently generate the cytotoxic hydroxyl radical(·OH)through the Fenton-like reaction.With the integration of multiple functions(i.e.,carrier-free ion and ROS delivery,tumor accumulation,p53 protein modulation,toxic·OH generation,and pH-activated MRI contrast)in a single nanosystem,Mn-ZnO_(2)NPs demonstrate its superiority as a promising nanotherapeutics for p53-mutated tumor therapy. 展开更多
关键词 p53-mutated tumor therapy Wild-type p53 protein Carrier-free nanoprodrug Mn-ZnO_(2)nanoparticle Reactive oxygen species
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A review in rational design of graphene toward advanced Li-S batteries 被引量:1
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作者 Haina Ci Zixiong Shi +2 位作者 Menglei Wang Yan He jingyu sun 《Nano Research Energy》 2023年第2期114-129,共16页
For lithium-sulfur(Li-S)batteries,the problems of polysulfides shuttle effect,slow dynamics of sulfur species and growth of lithium dendrite during charge/discharge processes have greatly impeded its practical develop... For lithium-sulfur(Li-S)batteries,the problems of polysulfides shuttle effect,slow dynamics of sulfur species and growth of lithium dendrite during charge/discharge processes have greatly impeded its practical development.Of core importance to advance the performances of Li-S batteries lies in the selection and design of novel materials with strong polysulfides adsorption ability and enhanced redox electrocatalytic behavior.Graphene,affording high electrical conductivity,superior carrier mobility,and large surface area,has presented great potentials in improving the performances of Li-S cells.However,the properties of intrinsic graphene are far enough to achieve the multiple management toward electrochemical catalysis of energy storage systems.In addition,a general and objective understanding of its role in Li-S systems is still lacking.Along this line,we summarize the design routes from three aspects,including defect engineering,dimension adjustment,and heterostructure modulation,to perfect the graphene properties.Thus-synthesized graphene materials are explored as multifunctional electrocatalysts targeting high-efficiency and long-lifespan Li-S batteries,based on which the regulating role of graphene is comprehensively analyzed.This project provides a perspective on the effective engineering management of graphene materials to boost Li-S chemistry,meanwhile promote the practical application process for graphene materials. 展开更多
关键词 GRAPHENE defect engineering dimension adjustment heterostructure modulation Li-S electrochemistry
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CO_(2)-promoted transfer-free growth of conformal graphene
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作者 Ruojuan Liu Zhe Peng +10 位作者 Xiaoli sun Zhaolong Chen Zhi Li Haina Ci Bingzhi Liu Yi Cheng Bei Jiang Junxiong Hu Wanjian Yin jingyu sun Zhongfan Liu 《Nano Research》 SCIE EI CSCD 2023年第5期6334-6342,共9页
Gaseous promotors have readily been adopted during the direct synthesis of graphene over insulators to enhance the growth quality and/or boost the growth rate.The understanding of the real functions of carbon-containi... Gaseous promotors have readily been adopted during the direct synthesis of graphene over insulators to enhance the growth quality and/or boost the growth rate.The understanding of the real functions of carbon-containing promotors has still remained elusive.In this study,we identify the critical roles of a representative CO_(2)promotor played in the direct growth of graphene.The comparative experimental trials validate CO_(2)as an effective modulator to decrease graphene nucleation density,improve growth kinetics,mitigate adlayer formation.The first-principles calculations illustrate that the generation of gas-phase OH species in CO_(2)-assisted system helps decrease the energy barriers of CH4 decomposition and carbon attachment to the growth front,which might be the key factor to allow high-quality direct growth.Such a CO_(2)-promoted strategy enables the conformal coating of graphene film over curved insulators,where the sheet resistance of grown graphene on quartz reaches as low as 1.26 kΩ·sq^(−1)at an optical transmittance of~95.8%.The fabricated endoscope lens based on our conformal graphene harvests an apoptosis of 82.8%for noninvasive thermal therapy.The work presented here is expected to motivate further investigations in the controllable growth of high-quality graphene on insulating substrates. 展开更多
关键词 chemical vapor deposition GRAPHENE carbon dioxide transfer-free growth promotor CONFORMAL
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