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Electrolyte-dependent formation of solid electrolyte interphase and ion intercalation revealed by in situ surface characterizations

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Journal of Energy Chemistry 2022年第4期31卷 718-726页

作者： Shiwen Li Chao Wang caixia meng Yanxiao Ning Guohui Zhang Qiang Fu State Key Laboratory of Catalysis iChEMDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

The formation of solid electrolyte interphase(SEI) and ion intercalation are two key processes in rechargeable batteries, which need to be explored under dynamic operating conditions. In this work, both planar and sandwich model lithium batteries consisting of Li metal | ionic liquid electrolyte | graphite electrode have been constructed and investigated by a series of in situ surface analysis platforms including atomic force microscopy, Raman and X-ray photoelectron spectroscopy. It is found that the choice of electrolyte, including the concentration and contents, has a profound effect on the SEI formation and evolution, and the subsequent ion intercalation. A smooth and compact SEI is preferably produced in highconcentration electrolytes, with FSI^(-) salt superior to TFSI^(-) salt, facilitating the lithiation/delithiation to achieve high capacity and excellent cycle stability, while suppressing the co-intercalation of electrolyte solvent ions. The innovative research scenario of well-defined model batteries in combination with multiple genuinely in situ surface analysis methods presented herein leads to insightful results, which provide valuable strategies for the rational design and optimization of practical batteries, and energy storage devices in general.

关键词： Lithium ion batteries Solid electrolyte interphase Ion intercalation In situ surface characterization Ionic liquid electrolyte

Visualizing surface-enriched Li storage with a nanopore-array model battery

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Nano Research 2023年第4期16卷 5026-5032页

作者： Shiwen Li Guohui Zhang Chao Wang caixia meng Xianjin Li Yanxiao Ning Qiang Fu State Key Laboratory of Catalysis iChEMDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China Department of Chemical Physics University of Science and Technology of ChinaHefei 230026China Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

The coupling of model batteries and surface-sensitive techniques provides an indispensable platform for interrogating the vital surface/interface processes in battery ***,we report a sandwich-format nanopore-array model battery using an ultrathin graphite electrode and an anodized aluminum oxide(AAO)*** porous framework of AAO regulates the contact pattern of the electrolyte with the graphite electrode from the inner side,while minimizing contamination on the outer *** model battery facilitates repetitive charge-discharge processes,where the graphite electrode is reversibly intercalated and deintercalated,and also allows for the in-situ characterizations of ion intercalation in the graphite *** ion distribution profiles indicate that the intercalating Li ions accumulate in both the inner and outer surface regions of graphite,generating a high capacity of~455 mAh·g^(-1)(theory:372 mAh·g^(-1)).The surface enrichment presented herein provides new insights towards the mechanistic understanding of batteries and the rational design strategies.

关键词： lithium ion batteries nanopore-array model battery in-situ surface characterization techniques ion intercalation surface enrichment effect

Step-confined thin film growth via near-surface atom migration

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Nano Research 2020年第6期13卷 1552-1557页

作者： caixia meng Junfeng Gao Rongtan Li Yanxiao Ning Yuan Chang Rentao Mu Qiang Fu Xinhe Bao State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China University of Chinese Academy of Sciences Beijing100039China Key Laboratory of Materials Modification by Laser Ion and Electron BeamsDalian University of TechnologyMinistry of EducationDalian116024China University of Science and Technology of China Hefei230026China

Understanding of thin film growth mechanism is crucial for tailoring film growth behaviors,which in turn determine physicochemical properties of the resulting ***,vapor-growth of tungsten carbide overlayers on W(110)surface is investigated by real time low energy electron *** surface growth is strongly confined by surface steps,which is in contrast with overlayer growth crossing steps in a so-called carpet-like growth mode for example in graphene growth on metal *** functional theory calculations indicate that the step-confined growth is caused by the strong interaction of the forming carbide overlayer with the substrate blocking cross-step growth of the ***,the tungsten carbide growth within each terrace is facilitated by the supply of carbon atoms from near-surface regions at high *** findings suggest the critical role of near-surface atom diffusion and step confinement effects in the thin film growth,which may be active in many film growth systems.

关键词： thin film growth tungsten carbide near-surface dopant low-energy electron microscopy(LEEM) step confinement

Revealing the effect of electrolyte coordination structures on the intercalation chemistry of batteries

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Journal of Energy Chemistry 2023年第6期81卷 149-156,I0006页

作者： Chao Wang Xianjin Li Guiming Zhong caixia meng Shiwen Li Guohui Zhang Yanxiao Ning Xianfeng Li Qiang Fu State Key Laboratory of Catalysis iChEMDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China Department of Chemical Physics University of Science and Technology of ChinaHefei 230026AnhuiChina Laboratory of Advanced Spectro-electrochemistry and Li-ion Batteries Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian116023LiaoningChina Division of Energy Storage Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023LiaoningChina

In-depth understanding of the electrolyte-dependent intercalation chemistry in batteries through direct operando/in situ characterizations is crucial for the development of the high-performance ***,taking the Al/graphite battery as a model system,the effect of electrolyte coordination structure on the intercalation processes has been investigated over the batteries with either 1-hexyl-3-methylimidazolium chloride(HMICl)-AlCl_(3) or 1-ethyl-3-methylimidazolium chloride(EMICl)-AlCl_(3) ionic liquid electrolyte using operando X-ray photoelectron spectroscopy(XPS)and X-ray *** a weaker anion-cation interaction in HMI-based electrolyte,the XPS-derived atomic ratio between cointercalated N and intercalated Al is 0.9,which is lower than 1.6 for EMI-based *** to the additional de-solvation process,the batteries with the HMI-based electrolyte show a lower ionic diffusion rate,capacity,and cycling performance,which agree with the operando characterization *** findings highlight the critical role of the electrolyte coordination structure on the(co-)intercalation chemistry.

关键词： Operando surface characterization Electrolyte coordination structure De-solvation Intercalation chemistry

Low-temperature and high-voltage planar micro-supercapacitors based on anti-freezing hybrid gel electrolyte

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Journal of Energy Chemistry 2022年第9期31卷 195-202,I0006页

作者： Manning Chen Xiaoyu Shi Xiaolei Wang Hanqing Liu Sen Wang caixia meng Yu Liu Liangzhu Zhang Yuanyuan Zhu Zhong-Shuai Wu College of Chemistry and Environment Shenyang University of TechnologyShenyang 110870LiaoningChina State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China Dalian National Laboratory for Clean Energy Chinese Academy of SciencesDalian 116023LiaoningChina

Micro-supercapacitors(MSCs)are considered as highly competitive power sources for miniaturized ***,narrow voltage window and poor anti-freezing properties of MSCs in conventional aqueous electrolytes lead to low energy density and limited environmental ***,we report the construction of low-temperature and high-energy-density MSCs based on anti-freezing hybrid gel electrolytes(HGE)through introducing ethylene glycol(EG)additives into aqueous LiCl *** EG partially destroys hydrogen bond network among water molecules,the HGE exhibits maximum electrochemical stability window of 2.7 V and superior anti-freezing features with a glass transition temperature of-62.8℃.Further,the optimized MSCs using activated carbon microelectrodes possess impressive volumetric capacitance of 28.9 F cm^(-3)and energy density of 10.3 mWh cm^(-3)in the voltage of 1.6 V,2.6 times higher than MSCs tested in 1.2 ***,the MSCs display 68.3%capacitance retention even at-30℃ compared to the value at 25℃,and ultra-long cyclability with 85.7%of initial capacitance after 15,000 times,indicating extraordinary low-temperature ***,our devices offer favorable flexibility and modular ***,this work provides a general strategy of realizing flexible,safe and anti-freezing microscale power sources,holding great potential towards subzero-temperature microelectronic applications.

关键词： Hybrid gel electrolyte Micro-supercapacitors Low temperature High voltage Graphene

Pt@h-BN core-shell fuel electrocatalysis confined cell electrocatalysts wit under outer shells

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Nano Research 2018年第6期11卷 3490-3498页

作者： mengmeng Sun Jinchao Dong Yang Lv Siqin Zhao caixia meng Yujiang Song Guoxiong Wang Jianfeng Li Qiang Fu Zhongqun Tian Xinhe Bao State Key Laboratory of Catalysis iChEM Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China University of Chinese Academy of Sciences Beijing 100049 China MOE Key Laboratory of Spectrochemical Analysis and Instrumentation State Key Laboratory of Physical Chemistry of Solid Surfaces iChEM College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology Dalian 116024 China

Two-dimensional （2D） materials such as graphene and hexagonal boron nitride （h-BN） can be used as robust and flexible encapsulation overlayers, which effectively protect metal cores but allow reactions to occur between inner cores and outer shells. Here, we demonstrate this concept by showing that Pt@h-BN core-shell nanocatalysts present enhanced performances in H2/O2 fuel cells. Electrochemical （EC） tests combined with operando EC-Raman characterizations were performed to monitor the reaction process and its intermediates, which confirm that Pt-catalyzed electrocatalytic processes happen under few-layer h-BN covers. The confinement effect of the h-BN shells prevents Pt nanoparticles from aggregating and helps to alleviate the CO poisoning problem. Accordingly, embedding nanocatalysts within ultrathin 2D material shells can be regarded as an effective route to design high-performance electrocatalysts.

关键词： electrocatalysis two-dimensional materials core-shell confinement catalysis operando Raman

新形势下五年制临床医学专业临床实习现状及应对策略

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护理研究 2019年第19期33卷 3457-3458页

作者：孟彩霞山西医科大学

[目的]了解新形势下五年制临床医学专业临床实习情况,[方法]应用自设的问卷对2016年—2018年某医科大学来院进行临床实习的五年制临床医学专业毕业生进行调查。[结果]近3年来院进行临床实习的五年制临床医学专业毕业生中考研率逐年提高,... 详细信息

[目的]了解新形势下五年制临床医学专业临床实习情况,[方法]应用自设的问卷对2016年—2018年某医科大学来院进行临床实习的五年制临床医学专业毕业生进行调查。[结果]近3年来院进行临床实习的五年制临床医学专业毕业生中考研率逐年提高,在50%以上,而同期就业率均低于考研率,呈低位徘徊状态;有效总实习时长为1~3个月和4~6个月的占比最高,均为33.33%,并列第一位,有效集中实习时间多集中在上一年度的7月、8月和下一年度的3月~6月,分别占39.83%和38.96%,合计占78.79%;愿意即使不考研也进行类似于备考的集中复习的人数占69.26%。[结论]新形势下五年制临床医学专业进入临床实习后并没有全员、足量完成规定的实习任务;学生临床实习有效时长和集中实习时间不足;学生对临床实习重视程度不够,且对临床实习与考研的认识片面。建议基于临床实习目的,结合实习生考研现状,统筹调整教学计划,力争做到临床实习与考研备考相兼顾,保证临床实习质量。

关键词：临床医学临床实习现状对策

基于经验小波变换的基因关联隐私保护实验研究

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湖南大学学报（自然科学版） 2020年第2期47卷 125-133页

作者：陈红松孟彩霞刘书雨北京科技大学计算机与通信工程学院北京100083 铁道警察学院河南郑州450053

为了解决某类风湿性关节炎与致病基因单核苷酸多态性(Single-Nucleotide Polymorphism,SNP)的相关度研究中,针对病人隐私保护强度与数据可用性的权衡问题,提出一种新型的基于经验小波变换(Empirical Wavelet Transform,EWT)的隐私保护方... 详细信息

为了解决某类风湿性关节炎与致病基因单核苷酸多态性(Single-Nucleotide Polymorphism,SNP)的相关度研究中,针对病人隐私保护强度与数据可用性的权衡问题,提出一种新型的基于经验小波变换(Empirical Wavelet Transform,EWT)的隐私保护方法.该方法通过对差分隐私加噪机制产生的数据进行EWT变换和分解,然后计算各EWT分量的峭度值并筛选出可能的噪声分量,去除一定的噪声分量后对信号进行重构得到新数据,基于该数据进行致病基因相关度排序.实验结果表明使用该方法能在保证差分隐私保护强度的情况下提高数据可用性,实现了隐私保护强度与数据可用性的合理权衡.

关键词：隐私保护经验小波变换差分隐私相关度数据可用性

Micro-strain regulation strategy to stabilize perovskite lattice based on the categories and impact of strain on perovskite solar cells

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Journal of Energy Chemistry 2025年第1期100卷 578-604页

作者： caixia Li Wenwu Liu Shiji Da Lingbin Kong Fen Ran State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of Technology School of Materials Science and Engineering Lanzhou University of Technology

Photovoltaic metal halide perovskite solar cells(PSCs) convert light to electricity more efficiently than crystalline silicon cells, and the cost of materials used to make them is lower than that of silicon *** efficiency is not a core issue affecting the application of perovskite solar cells in special *** present, stability is the major technical encounters that hinders its further commercial development. Microstrain in PSCs is currently a significant factor responsible for the device's instability. Strain-induced ion migration is widely believed to accelerate perovskite degradation even when external stimuli are ***, it is imperative to study strain to enhance the stability of PSCs. This paper reviews recent developments to understand strain's origin and effect mechanisms on performance of PSCs, including ion migration,failure behavior, defect formation, and its effect on photoelectric properties, stability, and ***, several well-known strain management strategies are systematically introduced based on the strain effect mechanism and strain engineering on the film, providing more clues for further preparation with increased stability. The manipulation of external physical strain applied from films to entire devices has been extensively studied. Furthermore, recommendations for future research directions and chemical approaches have been provided. It is emphasized that strain engineering plays a crucial role in improving the efficiency and longevity of PSCs. Tensile strain causes rapid degradation, while moderate compressive strain and external strain control could improve properties and stability. Efforts should focus on controlling compressive strain to mitigate residual tensile strain and introducing it in a controlled manner. Future research endeavors may focus on exploring these pathways to improve the efficiency and lifespan of PSCs.

关键词： Halide perovskite solar cells Strain origins Strain effects Strain management