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Manipulation strategy of cation inhomogeneity in perovskite solar cells 被引量:1
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作者 Jiale Sun Xuxia Shai +6 位作者 Weitao chen Shenchao Li Jinlan He Xinxing Liu Dongmei He Yue Yu Jiangzhao Chen 《Journal of Semiconductors》 2025年第5期9-12,共4页
In recent years, the research advancements have high-lighted the critical role of the A-site cation in determining the optoelectronic and physicochemical properties of organicinorganic lead halide perovskites. Mixed-c... In recent years, the research advancements have high-lighted the critical role of the A-site cation in determining the optoelectronic and physicochemical properties of organicinorganic lead halide perovskites. Mixed-cation perovskites(MCPs) have been extensively used as absorber thin films in perovskite solar cells(PSCs), achieving high power conversion efficiencies(PCE) over 26%^([1, 2]). 展开更多
关键词 cation inhomogeneity perovskite solar cells pscs perovskite solar cells absorber thin films mixed cation perovskites organicinorganic lead halide perovskites power conversion efficiency
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Long-term performance of lime-treated soil and chemical reaction identification
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作者 Yun Jiang Zi Ying +3 位作者 Fa Liu Chen Jiang Shanyong Wang Yongfeng Deng 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第8期5146-5154,共9页
Lime is widely used to modify clayey soils to enhance their physical and chemical properties,and lime-treated soil has become a key material in transportation infrastructure.Chemical reactions were identified through ... Lime is widely used to modify clayey soils to enhance their physical and chemical properties,and lime-treated soil has become a key material in transportation infrastructure.Chemical reactions were identified through laboratory tests from field samples collected from the subgrade after 30 years of operation to understand its long-term performance evolution.Exchangeable calcium,carbonated calcium,and total calcium were quantified using ethylenediaminetetraacetic acid(EDTA)titration,gasometric analysis,and the strong acid extraction method,respectively.These measurements enabled the evaluation of calcium transformation during the pozzolanic reaction,providing a quantitative characterization of pozzolanic progression in the lime-treated clay matrix.Evolutions in pH,electrical conductivity,and salinity were also tracked.Mechanical performance was assessed through maximal shear modulus(Gmax)and unconfined compressive strength(UCS)tests.Then,the microstructure and mineral composition were analyzed via scanning electron microscopy(SEM)and X-ray diffraction(XRD).Furthermore,with an extended curing period,the pH,electrical conductivity,salinity,and exchangeable calcium content were found to decrease gradually.In contrast,the carbonation-related calcium content increased,and the clay mineral structures were significantly altered.The significant increase in Gmax and UCS is attributed to the formation of calcium-aluminate-silicate-hydrate(C-(A)-S-H)for pozzolanic and carbonation reactions where the clay mineral is involved.SEM reveals the curled edges of clay minerals and the formation of a 3D network.Additionally,XRD patterns further confirm the presence of increasing amounts of amorphous phases within the 2θrange of 15°–32°,indicating the progression of the pozzolanic reaction. 展开更多
关键词 Lime-treated soil Chemical reactions identification Pozzolanic reaction Calcium cation dynamics Long-term performance
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Design of a cationic accelerator enabling ultrafast ion diffusion kinetics in aqueous zinc-ion batteries
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作者 Yawei Xiao Qianqian Gu +2 位作者 Haoyu Li Mengyao Li Yude Wang 《Journal of Energy Chemistry》 2025年第1期377-384,共8页
Aqueous zincion batteries are highly favored for grid-level energy storage owing to their low cost and high safety,but their practical application is limited by slow ion migration.To address this,a strategy has been d... Aqueous zincion batteries are highly favored for grid-level energy storage owing to their low cost and high safety,but their practical application is limited by slow ion migration.To address this,a strategy has been developed to create a cation-accelerating electric field on the surface of the cathode to achieve ultrafast Zn^(2+)diffusion kinetics.By employing electrodeposition to coat MoS_(2)on the surface of BaV_(6)O_(16)·3H_(2)O nanowires,the directional builtin electric field generated at the heterointerface acts as a cation accelerator,continuously accelerating Zn^(2+)diffusion into the active material.The optimized Zn^(2+)diffusion coefficient in CC@BaV-V_(6)O_(16)·3H_(2)@MoS_(2)(7.5×10^(8)cm^(2)s^(-1)) surpasses that of most reported V-based cathodes.Simultaneously,MoS_(2)serving as a cathodic armor extends the cycling life of the Zn-CC@BaV_(6)O_(16)·3H_(2)@MoS_(2)full batteries to over 10000 cycles.This work provides valuable insights into optimizing ion diffusion kinetics for high-performance energy storage devices. 展开更多
关键词 Internal electric field cationic accelerator lon diffusion kinetics Cathode modification strategy Aqueous zinc ion battery
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Cation-disordered Li_(2)FeTiO_(4) nanoparticles with multiple cation and anion redox for symmetric lithium-ion batteries
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作者 Wenjie Ma Yakun Tang +4 位作者 Yue Zhang Lang Liu Bin Tang Dianzeng Jia Yuliang Cao 《Chinese Chemical Letters》 2025年第9期664-671,共8页
Symmetric secondary batteries are expected to become promising storage devices on account of their low cost,environmentally friendly and high safety.Nevertheless,the further development of symmetric batteries needs to... Symmetric secondary batteries are expected to become promising storage devices on account of their low cost,environmentally friendly and high safety.Nevertheless,the further development of symmetric batteries needs to rely on bipolar electrodes with superior performance.Cation-disordered rocksalt(DRX)Li_(2)FeTiO_(4)shows promising properties as symmetric electrodes,based on the ability of iron to undergo multiple electrochemical reactions over a wide voltage window.Unfortunately,this cation-disordered structure would not provide a cross-path for the rapid migration of Li^(+),ultimately resulting in inferior electrochemical dynamics and cycle stability.Herein,Li_(2)FeTiO_(4)nanoparticles assembled by ultrafine nanocrystals are synthesized via a sol-gel method through an orderly reaction regulation strategy of precursor reactants.Such ultrafine nanocrystals increase the active sites to promote the reversibility of multi-cationic(e.g.,stable Fe^(2+)/Fe^(3+),Ti^(3+)/Ti^(4+)and moderated Fe^(3+)/Fe^(4+))and anionic redox,and maintain the DRX structure well during the cycling process.The half cells with nano-sized Li_(2)FeTiO_(4)as the cathode/anode exhibit a high reversible capacity of 127.8/500.8 mAh/g,respectively.Besides,the Li_(2)FeTiO_(4)//Li_(2)FeTiO_(4)symmetric full cell could provide a reversible capacity of 95.4 mAh/g at 0.1 A/g after 200 cycles.This hierarchical self-assembly by nanocrystal strategy could offer effective guidance for high-performance electrode design for rechargeable secondary batteries. 展开更多
关键词 Li_(2)FeTiO_(4) cation-disordered Reversible cationic and anionic redox Regulating nucleation rate Symmetric lithium-ion batteries
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Cation and anion modulation activates lattice oxygen for enhanced oxygen evolution 被引量:1
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作者 Mingxing Chen Zihe Du +8 位作者 Nian Liu Huijie Li Jing Qi Enbo Shangguan Jing Li Jiahao Cao Shujiao Yang Wei Zhang Rui Cao 《Chinese Journal of Catalysis》 2025年第2期282-291,共10页
Oxygen evolution reaction(OER)is often regarded as a crucial bottleneck in the field of renewable energy storage and conversion.To further accelerate the sluggish kinetics of OER,a cation and anion modulation strategy... Oxygen evolution reaction(OER)is often regarded as a crucial bottleneck in the field of renewable energy storage and conversion.To further accelerate the sluggish kinetics of OER,a cation and anion modulation strategy is reported here,which has been proven to be effective in preparing highly active electrocatalyst.For example,the cobalt,sulfur,and phosphorus modulated nickel hydroxide(denoted as NiCoPSOH)only needs an overpotential of 232 mV to reach a current density of 20 mA cm^(–2),demonstrating excellent OER performances.The cation and anion modulation facilitates the generation of high-valent Ni species,which would activate the lattice oxygen and switch the OER reaction pathway from conventional adsorbate evolution mechanism to lattice oxygen mechanism(LOM),as evidenced by the results of electrochemical measurements,Raman spectroscopy and differential electrochemical mass spectrometry.The LOM pathway of NiCoPSOH is further verified by the theoretical calculations,including the upshift of O 2p band center,the weakened Ni–O bond and the lowest energy barrier of rate-limiting step.Thus,the anion and cation modulated catalyst NiCoPSOH could effectively accelerate the sluggish OER kinetics.Our work provides a new insight into the cation and anion modulation,and broadens the possibility for the rational design of highly active electrocatalysts. 展开更多
关键词 Oxygen evolution reaction ELECTROCATALYSIS Lattice oxygen mechanism High-valent metal species cation and anion modulation
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Synergistic surface restructuring and cation mixing via ultrafast Joule heating enhancing ultrahigh-nickel cathodes for advanced lithium-ion batteries 被引量:1
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作者 Haoyu Wang Jinyang Dong +10 位作者 Meng Wang Yun Lu Hongyun Zhang Jinzhong Liu Yun Liu Na Liu Ning Li Qing Huang Feng Wu Yuefeng Su Lai Chen 《Journal of Energy Chemistry》 2025年第4期371-382,共12页
The implementation of ultrahigh-Ni cathodes in high-energy lithium-ion batteries(LIBs)is constrained by significant structural and interfacial degradation during cycling.In this study,doping-induced surface restructur... The implementation of ultrahigh-Ni cathodes in high-energy lithium-ion batteries(LIBs)is constrained by significant structural and interfacial degradation during cycling.In this study,doping-induced surface restructuring in ultrahigh-nickel cathode materials is rapidly facilitated through an ultrafast Joule heating method.Density functional theory(DFT)calculations,synchrotron X-ray absorption spectroscopy(XAS),and single-particle force test confirmed the establishment of a stable crystal framework and lattice oxygen,which mitigated H2-H3 phase transitions and improved structural reversibility.Additionally,the Sc doping process exhibits a pinning effect on the grain boundaries,as shown by scanning transmission electron microscopy(STEM),enhancing Li~+diffusion kinetics and decreasing mechanical strain during cycling.The in situ development of a cation-mixing layer at grain boundaries also creates a robust cathode/electrolyte interphase,effectively reducing interfacial parasitic reactions and transition metal dissolution,as validated by STEM and time-of-flight secondary ion mass spectrometry(TOF-SIMS).These synergistic modifications reduce particle cracking and surface/interface degradation,leading to enhanced rate capability,structural integrity,and thermal stability.Consequently,the optimized Sc-modified ultrahigh-Ni cathode(Sc-1)exhibits 93.99%capacity retention after 100 cycles at 1 C(25℃)and87.06%capacity retention after 100 cycles at 1 C(50℃),indicating excellent cycling and thermal stability.By presenting a one-step multifunctional modification approach,this research delivers an extensive analysis of the mechanisms governing the structure,microstructure,and interface properties of nickel-rich layered cathode materials(NCMs).These results underscore the potential of ultrahigh-Ni cathodes as viable candidates for advanced lithium-ion batteries(LIBs)in next-generation electric vehicles(EVs). 展开更多
关键词 Lithium-ion batteries Ultrahigh-nickel layered cathodes In situ surface doping cation mixing layer Structure and thermal stability
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New strategy for Mg-air battery voltage-efficiency synergy by engineering protective film with cation vacancies on Mg anode surface
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作者 Yuying He Qianyu Wang +6 位作者 Jinghuai Zhang Lele Wang Shujuan Liu Zehua Li Zhen Wei Hao Dong Xiaobo Zhang 《Journal of Materials Science & Technology》 2025年第10期24-41,共18页
Although the Mg-air battery with high theoretical energy density is desirable for the energy supply of marine engineering equipment,its applications remain limited due to the low actual discharge voltage and inferior ... Although the Mg-air battery with high theoretical energy density is desirable for the energy supply of marine engineering equipment,its applications remain limited due to the low actual discharge voltage and inferior Mg anode utilization rate.In addition to the microstructure of Mg alloy anodes,the properties of discharge product films are of great importance to the discharge performance.Herein,the discharge behaviors of Mg-Y-Zn alloys are first studied mainly from the perspective of film properties.Through contrastive analysis,it is found that the sufficient Y^(3+) produced during the discharge process can substitute Mg^(2+) in Mg(OH)_(2) to introduce effective cation vacancies.The Mg-Y-Zn anode with profuse cation vacancies in the product film shows a synergy of potential and efficiency,and this can be attributed to an increase in the migration pathway for Mg^(2+),reducing the diffusion over-potential caused by the protective product film.This study is expected to provide a new strategy from the perspective of cation vacancy design of discharge film for developing high-performance Mg-air batteries. 展开更多
关键词 Mg alloy Mg-air battery Product film cation vacancy Discharge performance
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Cations differentiation-induced core-shell heterostructure and mutual doping for achieving high-performance transitional metal carbonates electrode
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作者 Rui Zhang Xin Xu +8 位作者 Xin-Meng Li Wei-Jian Li Qing-Feng Fu Yong-Zhao Hou Shan Gao Lu-Chang Qin Guang-Wu Wen Xiao-Xiao Huang Dong Wang 《Rare Metals》 2025年第3期1701-1716,共16页
Transition metal carbonates(TMCs)hold great potential as high-performance electrodes for alkali metal-ion batteries,owing to multiple-ion storage mechanisms involving conversion process and electrocatalytic reaction.H... Transition metal carbonates(TMCs)hold great potential as high-performance electrodes for alkali metal-ion batteries,owing to multiple-ion storage mechanisms involving conversion process and electrocatalytic reaction.However,they still suffer from inferior electronic conductivity and volume variation during delithiation/lithiation.Heterostructure and heteroatoms doping offer immense promise in enhancing reaction kinetics and structural integrity,which unfortunately have not been achieved in TMCs.Herein,a unique TMCs heterostructure with Ni-doped MnCO_(3)as“core”and Mn-doped NiCO_(3)as“shell”,which is wrapped by graphene(NM@MN/RGO),is achieved by cations differentiation strategy.The formation process for core-shell NM@MN consists of epitaxial growth of NiCO_(3)from MnCO_(3)and synchronously mutual doping,owing to the similar crystal structures but different solubility product constant/formation energy of MnCO_(3)and NiCO_(3).In-situ electrochemical impedance spectroscopy,galvanostatic intermittent titration technique,differential capacity versus voltage plots,theoretical calculation and kinetic analysis reveal the superior electrochemical activity of the NM@MN/RGO to MnCO_(3)/RGO.The NM@MN/RGO shows excellent lithium storage properties(1013.4 mAh·g^(-1)at 0.1 A·g^(-1)and 760 mAh·g^(-1)after 1000 cycles at 2 A·g^(-1))and potassium storage properties(capacity decay rate of 0.114 mAh·g^(-1)per cycle).This work proposes an efficient cation differentiation strategy for constructing advanced TMC electrodes. 展开更多
关键词 Metal carbonates cations differentiation Core-shell structure Mutual doping ELECTRODE
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Limiting cationic mixing and lattice oxygen loss of single-crystalline Ni-rich Co-poor cathodes for high-voltage Li-ion batteries
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作者 Hujun Zhang Haifeng Yu +3 位作者 Ling Chen Muslum Demir Qilin Cheng Hao Jiang 《Green Energy & Environment》 2025年第8期1789-1796,共8页
Developing cost-effective single-crystalline Ni-rich Co-poor cathodes operating at high-voltage is one of the most important ways to achieve higher energy Li-ion batteries. However, the Li/O loss and Li/Ni mixing unde... Developing cost-effective single-crystalline Ni-rich Co-poor cathodes operating at high-voltage is one of the most important ways to achieve higher energy Li-ion batteries. However, the Li/O loss and Li/Ni mixing under high-temperature lithiation result in electrochemical kinetic hysteresis and structural instability. Herein, we report a highly-ordered single-crystalline LiNi0.85Co0.05Mn0.10O2(NCM85) cathode by doping K+and F-ions. To be specific, the K-ion as a fluxing agent can remarkably decrease the solid-state lithiation temperature by ~30°C, leading to less Li/Ni mixing and oxygen vacancy. Meanwhile, the strong transitional metal(TM)-F bonds are helpful for enhancing de-/lithiation kinetics and limiting the lattice oxygen escape even at 4.5 V high-voltage. Their advantages synergistically endow the single-crystalline NCM85 cathode with a very high reversible capacity of 222.3 mAh g-1. A superior capacity retention of 91.3% is obtained after 500 times at 1 C in pouch-type full cells, and a prediction value of 75.3% is given after cycling for 5000 h. These findings are reckoned to expedite the exploitation and application of high-voltage single-crystalline Ni-rich cathodes for next-generation Li-ion batteries. 展开更多
关键词 Ni-rich cathodes SINGLE-CRYSTALLINE cationic mixing Li-ion batteries
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Water-Restrained Hydrogel Electrolytes with Repulsion-Driven Cationic Express Pathways for Durable Zinc-Ion Batteries
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作者 Dewu Lin Yushuang Lin +10 位作者 Ruihong Pan Jiapei Li Anquan Zhu Tian Zhang Kai Liu Dongyu Feng Kunlun Liu Yin Zhou Chengkai Yang Guo Hong Wenjun Zhang 《Nano-Micro Letters》 2025年第8期320-332,共13页
The development of flexible zinc-ion batteries(ZIBs)faces a threeway trade-off among the ionic conductivity,Zn^(2+)mobility,and the electrochemical stability of hydrogel electrolytes.To address this challenge,we desig... The development of flexible zinc-ion batteries(ZIBs)faces a threeway trade-off among the ionic conductivity,Zn^(2+)mobility,and the electrochemical stability of hydrogel electrolytes.To address this challenge,we designed a cationic hydrogel named PAPTMA to holistically improve the reversibility of ZIBs.The long cationic branch chains in the polymeric matrix construct express pathways for rapid Zn^(2+)transport through an ionic repulsion mechanism,achieving simultaneously high Zn^(2+)transference number(0.79)and high ionic conductivity(28.7 mS cm−1).Additionally,the reactivity of water in the PAPTMA hydrogels is significantly inhibited,thus possessing a strong resistance to parasitic reactions.Mechanical characterization further reveals the superior tensile and adhesion strength of PAPTMA.Leveraging these properties,symmetric batteries employing PAPTMA hydrogel deliver exceeding 6000 h of reversible cycling at 1 mA cm^(−2) and maintain stable operation for 1000 h with a discharge of depth of 71%.When applied in 4×4 cm2 pouch cells with MnO_(2) as the cathode material,the device demonstrates remarkable operational stability and mechanical robustness through 150 cycles.This work presents an eclectic strategy for designing advanced hydrogels that combine high ionic conductivity,enhanced Zn^(2+)mobility,and strong resistance to parasitic reactions,paving the way for long-lasting flexible ZIBs. 展开更多
关键词 Zinc-ion battery Hydrogel electrolyte cation conduction Ionic repulsion Water state
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I_(2)-DMSO mediated tetra-functionalization of enaminones for the construction of novel furo[2,3:4,5]pyrimido[1,2-b]indazole skeletons via in situ capture of ketenimine cations
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作者 You Zhou Li-Sheng Wang +6 位作者 Shuang-Gui Lei Bo-Cheng Tang Zhi-Cheng Yu Xing Li Yan-Dong Wu Kai-Lu Zheng An-Xin Wu 《Chinese Chemical Letters》 2025年第1期277-282,共6页
The first-ever synthesis of the unknown furo[2,3:4,5]pyrimido[1,2-b]indazole skeleton was demonstrated based on the undiscovered tetra-functionalization of enaminones,with simple substrates and reaction conditions.The... The first-ever synthesis of the unknown furo[2,3:4,5]pyrimido[1,2-b]indazole skeleton was demonstrated based on the undiscovered tetra-functionalization of enaminones,with simple substrates and reaction conditions.The key to realizing this process lies in the multiple trapping of the in situ generated ketenimine cation by the 3-aminoindazole,which results in the formation of four new chemical bonds and two new rings in one pot.Moreover,the products of this new reaction were found to exhibit aggregationinduced emission(AIE)without modification. 展开更多
关键词 Unknown skeleton Tetra-functionalization Ketenimine cations Aggregation-induced emission
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Cationic Adsorption‑Induced Microlevelling Effect:A Pathway to Dendrite‑Free Zinc Anodes
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作者 Long Jiang Yiqing Ding +5 位作者 Le Li Yan Tang Peng Zhou Bingan Lu Siyu Tian Jiang Zhou 《Nano-Micro Letters》 2025年第9期16-28,共13页
Dendrite growth represents one of the most significant challenges that impede the development of aqueous zinc-ion batteries.Herein,Gd^(3+)ions are introduced into conventional electrolytes as a microlevelling agent to... Dendrite growth represents one of the most significant challenges that impede the development of aqueous zinc-ion batteries.Herein,Gd^(3+)ions are introduced into conventional electrolytes as a microlevelling agent to achieve dendrite-free zinc electrodeposition.Simulation and experimental results demonstrate that these Gd^(3+)ions are preferentially adsorbed onto the zinc surface,which enables dendritefree zinc anodes by activating the microlevelling effect during electrodeposition.In addition,the Gd^(3+)additives effectively inhibit side reactions and facilitate the desolvation of[Zn(H_(2)O)_(6)]^(2+),leading to highly reversible zinc plating/stripping.Due to these improvements,the zinc anode demonstrates a significantly prolonged cycle life of 2100 h and achieves an exceptional average Coulombic efficiency of 99.72%over 1400 cycles.More importantly,the Zn//NH_(4)V_(4)O_(10)full cell shows a high capacity retention rate of 85.6%after 1000 cycles.This work not only broadens the application of metallic cations in battery electrolytes but also provides fundamental insights into their working mechanisms. 展开更多
关键词 Aqueous zinc-ion batteries Zinc anodes Rare-earth cations Microlevelling Zinc dendrites
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Weakly coordinating cationic polymer electrolytes for fast-charging solid-state lithium-metal batteries
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作者 Soohyoung Lee Kyeong-Seok Oh +4 位作者 Ji Eun Lee Sun-Phil Han Hong-I Kim Sang Kyu Kwak Sang-Young Lee 《Journal of Energy Chemistry》 2025年第6期243-251,I0006,共10页
Despite the growing interest in fast-cha rging solid-state lithium(Li)-metal batteries(SSLMBs),their practical implementation has yet to be achieved,primarily due to an incomplete understanding of the disparate and of... Despite the growing interest in fast-cha rging solid-state lithium(Li)-metal batteries(SSLMBs),their practical implementation has yet to be achieved,primarily due to an incomplete understanding of the disparate and often conflicting requirements of the bulk electrolyte and the electrode-electrolyte interphase.Here,we present a weakly coordinating cationic polymer electrolyte(WCPE)specifically designed to regulate the Li^(+)coordination structure,thereby enabling fast-charging SSLMBs.The WCPE comprises an imidazolium-based polycationic matrix combined with a succinonitrile(SN)-based highconcentration electrolyte.Unlike conventional neutral polymer matrices,the polycationic matrix in the WCPE competes with Li^(+)for interactions with SN,weakening the original coordination between SN and Li^(+).This modulation of SN-Li^(+)interaction improves both Li^(+)conductivity of the WCPE(σ_(Li^(+))=1.29mS cm^(-1))and redox kinetics at the electrode-electrolyte interphase.Consequently,SSLMB cells(comprising LiFePO_(4)cathodes and Li-metal anodes)with the WCPE achieve fast-charging capability(reaching over 80%state of charge within 10 min),outperforming those of previously reported polymer electrolytebased SSLMBs. 展开更多
关键词 cationic polymer electrolytes Weak coordination Electrode-electrolyte interphase Fast-charging Solid-state lithium-metal batteries
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Synthesis of Allyl Telechelic Poly(4-acetoxystyrene) via Living Cationic Polymerization and Electrophilic Substitution of Allyltrimethylsilane
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作者 Yu Zhu Shuai Wen +4 位作者 Hui Li Tao Zhuang Lu Li Qiang Liu Shou-Ke Yan 《Chinese Journal of Polymer Science》 2025年第6期1043-1049,I0012,共8页
Living cationic polymerization of 4-acetoxystyrene(STO)was conducted in CH_(2)Cl_(2) at-15℃ using a dicumyl chloride(DCC)/SnCl_(4)/nBu_(4)NBr initiating system.Impurity moisture initiation was inhibited by adding pro... Living cationic polymerization of 4-acetoxystyrene(STO)was conducted in CH_(2)Cl_(2) at-15℃ using a dicumyl chloride(DCC)/SnCl_(4)/nBu_(4)NBr initiating system.Impurity moisture initiation was inhibited by adding proton trap 2,6-di-tert-butylpyridine(DTBP),and the controlled initiation of DCC was confirmed by ^(1)H nuclear magnetic resonance(^(1)H-NMR)spectroscopy and matrix-assisted laser desorption ionization time-offlight mass(MALDI-TOF-MS)spectrometry.The polymerization kinetics were analyzed to for optimizing the polymerization rate.Allyl-telechelic PSTOs(allyl-PSTO-allyl)with molecular weight(Mn)range of 3540–7800 g/mol and narrow molecular weight dispersity(Mw/Mn)about 1.25 were prepared through nucleophilic substitution with allyltrimethylsilane(ATMS)at approximately 40%monomer conversion.The experimental results indicate that the substitution efficiency of ATMS increased with higher ATMS concentration,temperature,and extended reaction time.Nearly unity ally-functionality for allyl-PSTO-allyl was achieved by adding sufficient SnCl_(4) prior to the substitution. 展开更多
关键词 Living cationic polymerization 4-Acetoxystyrene Allyl-telechelic polymer Nucleophilic substitution
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Effective suppression of surface cation segregations on double perovskite oxides through entropy engineering
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作者 Zhe Wang Mengke Yuan +5 位作者 Juntao Gao Hongru Hao Jingwei Li Lingling Xu Zhe Lv Bo Wei 《Journal of Rare Earths》 2025年第2期345-353,I0005,共10页
Cation segregation on cathode surfaces plays a key role in determining the activity and operational stability of solid oxide fuel cells(SOFCs).The double perovskite oxide PrBa_(0.8)Ca_(0.2)Co_(2)O_(5+δ)(PBCC)has been... Cation segregation on cathode surfaces plays a key role in determining the activity and operational stability of solid oxide fuel cells(SOFCs).The double perovskite oxide PrBa_(0.8)Ca_(0.2)Co_(2)O_(5+δ)(PBCC)has been widely studied as an active cathode but still suffer from serious detrimental segregations.To enhance the cathode stability,a PBCC derived A-site medium-entropy Pr_(0.6)La_(0.1)Nd_(0.1)Sm_(0.1)Gd_(0.1)Ba_(0.8)Ca_(0.2)Co_(2)O_(5+δ)(ME-PBCC)oxide was prepared and its segregation behaviors were investigated under different conditions.Compared with initial PBCC oxide,the segregations of BaO and Co_(3)O_(4)on the surface of ME-PBCC material are significantly suppressed,especially for Co_(3)O_(4),which is attributed to its higher configuration entropy.Our results also confirm the improved electrochemical performance and structural stability of ME-PBCC material,enabling it as a promising cathode for SOFCs. 展开更多
关键词 Solid oxide fuel cells CATHODE Double perovskite Configuration entropy cation segregation Rare earths
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Cationic covalent organic framework nanocarriers integrating both efficient gene silencing and real-time gene detection
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作者 Ziqin Li Kai Hao +1 位作者 Longwei Xiang Huayu Tian 《Chinese Chemical Letters》 2025年第4期268-271,共4页
The occurrence,development,and metastasis of tumors often entail abnormal expression of genetic substances.Monitoring and regulating changes in intracellular nucleic acid substances hold promise for achieving accurate... The occurrence,development,and metastasis of tumors often entail abnormal expression of genetic substances.Monitoring and regulating changes in intracellular nucleic acid substances hold promise for achieving accurate tumor diagnosis and effective treatment.However,the effectiveness of integrated tumor diagnosis and treatment based on functional nucleic acids still needs to be improved.In this study,we engineered a multifunctional nucleic acid delivery system grounded in a cationic covalent organic framework carrier.This system not only showcases effective gene silencing but also boasts high sensitivity in detecting miR21 levels within tumor cells,enabling real-time monitoring of tumor gene therapy efficacy.The construction of this integrated functional nucleic acid delivery platform provides new ideas for precise tumor detection and effective tumor treatment. 展开更多
关键词 Tumor diagnosis Cancer therapy Nucleic acid delivery cationic COF Gene silencing
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Constructing main/side chain dual-cation poly(mequitazine-terphenyl piperidinium)anion exchange membranes for high-performance fuel cells
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作者 Shiyao Sun Jialin Zhao +7 位作者 Yijia Lei Jingyi Wu Jian Gao Na Li Jiayao Yang Jiahao Lu Liying Yin Zhe Wang 《Materials Reports(Energy)》 2025年第2期68-76,I0002,共10页
Anion exchange membranes(AEMs)combining high hydroxide conductivity and alkali-resistant stability have become a major challenge for the long-term development of anion exchange membrane fuel cells(AEMFCs).Here,we desi... Anion exchange membranes(AEMs)combining high hydroxide conductivity and alkali-resistant stability have become a major challenge for the long-term development of anion exchange membrane fuel cells(AEMFCs).Here,we designed a series of poly(mequitazine-terphenyl piperidinium)(QPMTP-X)AEMs with dual-functionalized quaternary ammonium cations by introducing a certain proportion of large steric hindrance mequitazine(MEQ)molecular building unit into the poly(aryl piperidinium)backbone.QPMTP-X retains the excellent mechanical properties of the poly(aryl piperidinium),while also combining the alkaline stability and high ionic conductivity exhibited by MEQ with flexible quinuclidinium side chains,achieving an overall improvement of membrane performance.Notably,QPMTP-30 exhibits an ultra-high conductivity of up to 206.83 mS cm^(-1)and excellent alkaline stability(over 95%conductivity is maintained after 1000 h of conditioning in 2 M NaOH at 80℃).In fuel cell performance test,QPMTP-30 achieves a peak power density(PPD)of 974.5 mW cm^(-2)and operates stably at 80℃for more than 60 h(0.1 A cm^(-2)).Incorporating large steric hindrance building blocks and multi-cations into the poly(aryl piperidinium)backbone not only synergizes the development of highperformance AEMs but also opens up new ideas for the structural design of future AEMs. 展开更多
关键词 Anion exchange membranes Mequitazine Dual cations High efficiency ion transport Fuel cells
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Integrated mechanisms of phytochemicals from plant-based functional foods in modulation detoxification pathways for cancer prevention: A review
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作者 Isabel Teixeira Carvalho 《Journal of Nutritional Oncology》 2025年第3期79-88,共10页
Cancer remains a significant challenge to public health worldwide and ranks among the leading contributors to mortality in diverse populations.This persistent impact underscores the need for proactive approaches to red... Cancer remains a significant challenge to public health worldwide and ranks among the leading contributors to mortality in diverse populations.This persistent impact underscores the need for proactive approaches to reduce its incidence.Chemoprevention focuses on interrupting tumor development through naturally occurring compounds,particularly plant-derived bioactive com-pounds.These phytochemicals exert protective effects by modulating key molecular pathways and enhancing detoxification.Of particular interest are those that regulate phase I and II enzymes,facilitating carcinogen elimination and mitigating cellular damage associated with cancer progression.This review examines phytochemicals from plant-derived functional foods that enhance detoxification pathways for cancer prevention,summarizing current evidence and future directions for their clinical application and dietary integration.Emphasis is placed on specific bioactive constituents,such as sulforaphane from cruciferous vegetables,organosulfur compounds in garlic,betanin from beetroot,a spectrum of citrus fruitflavonoids includingβ-cryptoxanthin,hesperidin,and nobiletin,epigallocatechin-3-gallate from green tea,and curcumin derived from turmeric.These naturally occurring compounds regulate enzymatic pathways involved in xenobiotic metabolism,underscoring their relevance in nutritional oncology.Findings from diverse experimental models show they inhibit phase I enzymes,induce phase II detox enzymes,activate the Nrf2 signaling pathway,and modulate gene expression epigenetically.Collectively,these multifaceted actions contribute to their protective role against carcinogenesis.Although natural approaches show promise for cancer prevention,they face challenges related to bioavailability,standardization,and clinical validation,necessitating further research for effective integration into evidence-based oncology. 展开更多
关键词 CHEMOPREVENTION Natural functional nutrition Phytochemical-rich foods Detoxification pathways Emerging science
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Reversed rectification of ionic liquid/water mixtures in conical nanochannels
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作者 Dongna Li Qian Sheng +4 位作者 Yewei Song Zirong Liu Yunbiao Zhao Kun Zhu Jianming Xue 《Nanotechnology and Precision Engineering》 2025年第1期94-100,共7页
Because of their remarkable properties,room-temperature ionic liquids(RTILs)are used widely in electrochemistry,fuel cells,supercapacitors,and even DNA sequencing,and many of these applications involve the transport o... Because of their remarkable properties,room-temperature ionic liquids(RTILs)are used widely in electrochemistry,fuel cells,supercapacitors,and even DNA sequencing,and many of these applications involve the transport of RTILs in nanoscale media.Particularly for single-molecule detection,the RTIL must be mixed with a solvent(e.g.,water)so that the electrolyte has both high viscosity and conductivity to obtain excellent signals.If a RTIL contains a quantity of water in bulk,this has a significant effect on its properties(e.g.,the electrochemical window),thereby limiting some applications.However,the physicochemical properties of RTILs containing water in nanoconfined spaces remain unclear,especially their ionic transport behavior.Therefore,reported here is a study of the ionic transport behavior of mixed RTIL/water solutions at the nanoscale using a single conical nanochannel as a nanofluidic platform.The conductivity of the mixtures in the nanoconfined space was closely related to the nanochannel size,and highly diluted mixed solutions resulted in a nonlinear rectificationreversed current,which was possibly due to the adsorption of cations on the nanochannel wall.The maximum rectification ratio was 114,showing excellent rectification that could be used to realize newly conceptualized nanofluidic diodes.In summary,this work provides an exhaustive understanding of the nonlinear ion transport of RTIL/water mixtures and a theoretical foundation for applying RTILs in energy storage and conversion and bio-sensing. 展开更多
关键词 Ionic liquid Single conical nanochannel CONDUCTIVITY Reversed rectification
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High thermal conductivity in Ga_(2)TeO_(6) crystals:Synergistic effects of rigid polyhedral frameworks and stereochemically inert cations
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作者 Ziyi Liu Feifei Guo +3 位作者 Tingting Cao Youxuan Sun Xutang Tao Zeliang Gao 《Chinese Journal of Structural Chemistry》 2025年第4期37-43,共7页
The investigation of thermal transport properties of materials has become increasingly important in technological applications,including thermal management and energy conversion.Recently,ultrahigh or low thermal condu... The investigation of thermal transport properties of materials has become increasingly important in technological applications,including thermal management and energy conversion.Recently,ultrahigh or low thermal conductivity has been reported in nitride,boride,and chalcogenide by different strategies.However,the strategy to design oxide crystals with unique thermal properties is also a challenge.In this work,a new ternary oxide crystal Ga_(2)TeO_(6) is designed and expected to show high thermal conductivity due to its lone pairs-free octahedra connected along the caxis by sharing edges.The thermal conductivities of Ga_(2)TeO_(6) crystal are determined to be 19.2 and 23.9Wm^(-1) K^(-1) along the a-and c-axis directions at 323 K,respectively,which are significantly higher than those of most reported oxide crystals.First-principles calculations and crystal structure analyses reveal that the Ga_(2)TeO_(6) crystal shows high sound velocity and weak lattice anharmonicity due to lone pairs-free octahedra and highly symmetric group arrangement.The results suggest that much attention must be paid to the polyhedron with lone pairs and its arrangement in materials design to balance the functions and thermal properties. 展开更多
关键词 High thermal conductivity Oxide functional crystal Polyhedral frameworks Stereochemically inert cations
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