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Nano Research 2017年第10期10卷 3585-3595页

作者： Xuan Hou chuanchuan li Huayun Xu liqiang Xu Key Laboratory of Colloid & Interface Chemistry (Shandong University) Ministry of Education and School of Chemistry and Chemical Engineering Shandong University Jinan 250100 China

NaFeTiO4 nanorods of high yields （with diameters in the range of 30-50 nm and lengths of up to 1-5 μm） were synthesized by a facile sol-gel method and were utilized as an anode material for sodium-ion batteries for the first time. The obtained NaFeTiO4 nanorods exhibit a high initial discharge capacity of 294 mA·h·g^-1 at 0.2 C （1 C = 177 mA·g^-1）, and remain at 115 mA·h·g^-1 after 50 cycles. Furthermore, multi-walled carbon nanotubes （MWCNTs） were mechanically milled with the pristine material to obtain NaFeTiO4/MWCNTs. The NaFeTiO4/MWCNTs electrode exhibits a significantly improved electrochemical performance with a stable discharge capacity of 150 mA·h·g^-1 at 0.2 C after 50 cycles, and remains at 125 mA·h·g^-1 at 0.5 C after 420 cycles. The NaFeTiO4/MWCNTs//Na3V2（PO4）3/C full cell was assembled for the first time; it displays a discharge capacity of 70 mA·h·g^-1 after 50 cycles at 0.05 C, indicating its excellent performances. X-ray photoelectron spectroscopy, ex situ X-ray diffraction, and Raman measurements were performed to investigate the initial electrochemical mechanisms of the obtained NaFeTiO4/MWCNTs.

关键词： nanorods sodium-ion batteries multi-walled carbon nanotubes full cell

Single-atom catalysts supported on graphene/electride heterostructures for the enhanced sulfur reduction reaction in lithium-sulfur batteries

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Journal of Energy Chemistry 2024年第10期97卷 738-746,I0015页

作者： Siyun Qi chuanchuan li Gang Chen Mingwen Zhao School of Physics and Electronics Shandong Normal UniversityJinan 250358ShandongChina Qingdao Industrial Energy Storage Research Institute Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 26611ShandongChina School of Physics&State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100ShandongChina

Single-atom catalysts(SACs)hold great promise in addressing the sluggish kinetics of the sulfur reduction reaction(SRR)in lithium-sulfur(li-S)batteries for their unique catalytic activity and maximum atom *** these SACs must be dispersed on solid substrates,the underlying support is usually limited to carbon materials that have a poor ability to modulate the coordination environment and electronic structures of single atoms,and consequently their catalytic activity toward the SRR is *** we propose two-dimensional(2D)graphene/electride heterostructu res as substrates to enhance the catalytic activities of SACs for li-S batteries.2D electrides featuring the anionic electron gas on their surface enable efficient electron transfer to SACs,which alters their electronic structures,resulting in the shifts of the d orbital and Fermi *** unique electronic structure decreases the filling of antibonding states such that the bonding with adsorbates at active sites is *** demonstrate the enhanced catalytic performance of SACs in terms of the Gibbs free energy of SRR and li_(2)S *** addition,a universal descriptor for the rapid screening of SACs is established by a linear regression fitting *** work provides a new design strategy to modulate SAC activity through electrides for li-S batteries.

关键词： Electrides DFT calculations Kinetics Universal descriptors Charge transfers

Titanium nitride hollow nanospheres with strong lithium polysulfide chemisorption as sulfur hosts for advanced lithium-sulfur batteries

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Nano Research 2018年第8期11卷 4302-4312页

作者： chuanchuan li Jingjing Shi lin Zhu Yingyue Zhao Jun Lu liqiang Xu Key Laboratory of Colloid & Interface Chemistry (Shandong University) Ministry of Education School of Chemistry and Chemical Engineering Shandong University Jinan 250 I00 China Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) Nankai University Tianjin 300071 China Faculty of Science Beijing University of Chemical Technology Beijing 100029 China

lithium-sulfur batteries are promising electrochemical energy storage devices because of their high theoretical specific capacity and energy density. An ideal sulfur host should possess high conductivity and embrace the physical confinement or strong chemisorption to dramatically suppress the polysulfide dissolution. Herein, uniform TiN hollow nanospheres with an average diameter of N 160 nm have been reported as highly efficient lithium polysulfide reservoirs for high-performance lithium-sulfur batteries. Combining the high conductivity and chemical trapping of lithium polysulfides, the obtained S/TiN cathode of 70 wt.% sulfur content in the composite delivered an excellent long-life cycling performance at 0.5C and 1.0C over 300 cycles. More importantly, a stable capacity of 710.4 mAh.g-1 could be maintained even after 100 cydes at 0.2C with a high sulfur loading of 3.6 mg-cm-1 The nature of the interactions between TiN and lithium polysulfide species was investigated by X-ray photoelectron spectroscopy studies. Theoretical calculations were also carried out and the results revealed a strong binding between TiN and the lithium polysulfide species. It is expected that this dass of conductive and polar materials would pave a new way for the high-energy lithium-sulfur batteries in the future.

关键词： TiN hollow spheres lithium-sulfur batteries polysulfide trapping density functional theory(DFT) calculations

Mesoporous Mn-Sn bimetallic oxide nanocubes as long cycle life anodes for li-ion half/full cells and sulfur hosts for li-S batteries

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Nano Research 2018年第7期11卷 3555-3566页

作者： Yanyan He liqiang Xu chuanchuan li Xiaoxia Chen Gang Xu Xiaoyun Jiao Key Laboratory of Colloid & Interface Chemistry (Shandong University) Ministry of Education School of Chemistry and Chemical Engineering Shandong University Jinan 250100 China College of Chemistry Chemical Engineering and Materials Science Shandong Normal University Jinan 250014 China

Mesoporous Mn-Sn bimetallic oxide （BO） nanocubes with sizes of 15-30 run show outstanding stable and reversible capacities in lithium ion batteries CliBs）, reaching 856.8 mAh.g-1 after 400 cycles at 500 mA·g^-1 and 506 mAh·g^-1 after 850 cycles at 1,000 mA·g^-1. The prelimLnary investigation of the reaction mechanism, based on X-ray diffraction measurements, indicates the occurrence of both conversion and alloying-dealloying reactions in the Mn-Sn bimetallic oxide electrode. Moreover, Mn-Sn BO//liCoO2 li-ion full cells were successfully assembled for the first time, and found to deliver a relatively high energy density of 176.25 Wh·kg^-1 at 16.35 W·kg^-1 （based on the total weight of anode and cathode materials）. The superior long-term stability of these materials might be attributed to their nanoscale size and unique mesoporous nanocubic structure, which provide short li^＋ diffusion pathways and a high contact area between electrolyte and active material. In addition, the Mn-Sn BOs could be used as advanced sulfur hosts for lithium-sulfur batteries, owing to their adequate mesoporous structure and relatively strong chemisorption of lithium polysulfide. The present results thus highlight the promising potential of mesoporous Mn-Sn bimetallic oxides for application in li-ion and li-S batteries.

关键词： mesoporous nanocube structure ex situ X-ray diffraction(XRD) li-ion full cell long cycle life sulfur host

Global warming accelerates the upfreezing of permafrost in arid middle Tianshan Mountains

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Chinese Science Bulletin 2013年第31期58卷 3806-3814页

作者： li chuanchuan CHEN YiXin NIE ZhenYu CUI ZhiJiu liU GengNian College of Urban and Environmental Sciences Peking University

Upfreezing is an important geomorphic process in the periglacial *** is a product of cold climate and thus an important part of the cryospheric *** on the long-term positioning observations in the source area of the Urumqi River,this article represents an in-depth discussion of the characteristics of sorted circles and upfreezing mechanisms in the Tianshan *** the source area of the Urumqi River,the intensity of upfreezing is the highest within the top 25 cm near the surface,while targets with a diameter of 3 cm are least affected by *** is no distinct difference between the centre with fine grains and the margin with coarse debris within the same sorted circle in terms of the intensity of *** correlation analysis demonstrates that temperature plays an important role in upfreezing and the development of sorted circles.A long-time positioning observation of sorted circles reveals that periglacial landforms are sensitive to regional climate change and respond quickly to the temperature increase of the recent two *** upfreezing was found to be due to increased soil moisture content.

关键词：全球变暖天山区域气候变化乌鲁木齐河干旱冻土定位观测温度上升

Slow light in tapered slot photonic crystal waveguide

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Chinese Science Bulletin 2009年第20期54卷 3658-3662页

作者： WU Jun li YanPing YANG chuanchuan PENG Chao WANG ZiYu State Key Laboratory on Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science Peking University Beijing 100871 China

A slotted single-mode photonic crystal waveguide with a linear tapered slot is presented to realize slow light,whose dispersion curve is shifted by changing the slot *** the slot width is reduced,the band curve shifts in the tapered structure,and the group velocity of light approach zero at the cut-off ***,different frequency components of the guided light are slowed down even localized along the propagation direction inside a tapered slot photonic crystal ***,this structure can confine slow light-wave in a narrow slot waveguide,which may effectively enhance the interaction between slow light and the low-index wave-guiding materials filled in the *** addition,this tapered slot structure can be used to compensate group velocity dispersion of slow light by modifying the structure,thus opening the opportunity for ultra-wide bandwidth slow light.

关键词：光子晶体波导锥形槽结构单一模式色散曲线变化曲线截止频率传播方向

Human Capital Development and Its Influence on FDI Withdrawal:An Empirical Analysis

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China & World Economy 2023年第5期31卷 116-134页

作者： chuanchuan li Lei li Haodan Tang Yanyan Zheng Fangming Gong The Academy of China Open Economy Studies and Institute of International Economy University of International Business and EconomicsChina Center for Transnationals'Studies and Laboratory for Economic Behaviors and Policy Simulation Nankai UniversityChina School of International Business Southwestern University of Finance and EconomicsChina School of International Business Tianjin Foreign Studies UniversityChina International Business Strategy Institute University of International Business and EconomicsChina

This paper examines the causal effect of human capital expansion on the exit of foreignowned firms using the difference-in-differences method together with a quasi-natural experiment involving the expansion of higher education in China in *** expansion of human capital reduces the probability of the exit of foreign-owned firms significantly This conclusion remains robust under a series of tests,including changing the sample range,adjusting the identification method,and considering the trade *** of the mechanism indicates that human capital expansion reduces the exit probability of foreign-owned firms by stimulating innovation,improving production efficiency,and optimizing the quality of input and output *** with higher asset specificity are also more likely to restrain the exit of foreign-owned firms through human capital ***,the findings of this study provide a good insight into the exit behavior of FDI in China from the perspective of human capital.

关键词： exit of foreign-owned firms human capital mechanism analysis intermediat input

Late Pleistocene glaciation of the Changbai Mountains in northeastern China

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Chinese Science Bulletin 2008年第17期53卷 2672-2684页

作者： ZHANG Wei NIU YunBo YAN ling CUI ZhiJiu li chuanchuan MU KeHua College of Urban and Environment Sciences Liaoning Normal University Dalian 116029 China Department of Geography Peking University Beijing 100087 China

The Changbai Mountains (2749 m a.s.l.) in northeastern China are one of the typical mountain regions with glaciation since late Pleistocene as evidenced by well-preserved erosive and accumulative landforms at elevations above 2000 m a.s.l. formed by glaciers around the crater lake, Tianchi Lake. Cirque glaciers developed on both the inner and outer sides of the volcanic cone. Well-preserved cirques, glacial trough valleys, glacial threholds, polished surfaces of the glacial erratics and the moraine ridges indicate that several glaciation processes took place during the last glacial period in this region. Results of optically stimulated luminescence (OSL) dating on the moraine sediments, and the K/Ar, ther- mal ionization mass spectrometry (TIMS), electronic spinning resonance (ESR) dating on the volcanic rocks suggest two periods of glacier advances. One is named the Black Wind Mouth glacier advance taking place on the west and north slopes of the volcanic cone at an elevation of 2000―2100 m a.s.l., which is dated to about 20 ka, being the result of the Last Glacial Maximum (LGM). The other is named the Meteorological Station glacier advance at the elevation of 2400―2600 m a.s.l., dated to 11 ka during the late glacial period, and is tentatively correlated to the Younger Dryas stage. The scope of the former glacier advance is larger than that of the latter. Regional comparisons showed that the glacial sequences in the Changbai Mountains are similar to other glaciated areas in eastern Asia during the later part of the last glacial cycle.

关键词：晚更新世冰川作用末次冰期长白山火山岩中国

Dandelion-like Bi_(2)S_(3)/rGO hierarchical microspheres as high-performance anodes for potassium-ion and half/full sodium-ion batteries

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Nano Research 2021年第12期14卷 4696-4703页

作者： Xiuping Sun Lu Wang chuanchuan li Debao Wang Iqbal Sikandar Ruxia Man Fang Tian Yitai Qian liqiang Xu Key Laboratory of Colloid and Interface Chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringShandong UniversityJinan250100China College of Chemistry and Molecular Engineering Qingdao University of Science and TechnologyQingdao266042China Shandong Provincial Key Laboratory/Collaborative Innovation Center of Chemical Energy Storage&Novel Cell Technology Liaocheng UniversityLiaocheng City252059China

Sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs) have been considered as attractive alternatives for next-generation battery systems, which have promising application potential due to their earth abundance of potassium and sodium, high capacity and suitable working potential, however, the design and application of bi-functional high-performance anode still remain a great challenge up to date. Bismuth sulfide is suitable as anode owing to its unique laminar structure with relatively large interlayer distance to accommodate larger radius ions, high theoretical capacity and high volumetric capacity etc. In this study, dandelion-like Bi_(2)S_(3)/rGO hierarchical microspheres as anode material for PIBs displayed reversible capacity, and 206.91 mAh·g^(−1) could be remained after 1,200 cycles at a current density of 100 mA·g^(−1). When applied as anode materials for SIBs, 300 mAh·g^(−1) could be retained after 300 cycles at 2 A·g^(−1) and its initial Coulombic efficiency is as high as 97.43%. Even at high current density of 10 A·g^(−1), 120.3 mAh·g^(−1) could be preserved after 3,400 cycles. The Na_(3)V_(2)(PO_(4))_(3)@rGO//Bi_(2)S_(3)/rGO sodium ion full cells were successfully assembled which displays stable performance after 60 cycles at 100 mA·g^(−1). The above results demonstrate that Bi2S3/rGO has application potential as high performance bi-functional anode for PIBs and SIBs.

关键词： potassium ion battery sodium ion battery full cell Bi2S3 anode material

Environmental evolution of Gongwang Mountains during Holocene in northeastern Yunnan,China

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Global Geology 2008年第3期11卷 156-167页

作者： Wei ZHANG chuanchuan li Zhijiu CUI Jinliang FENG College of Urban and Environmental Sciences Liaoning Normal University Dalian 116029 Liaoning China College of Environmental Sciences Peking University Beijing 100871 China Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China

This paper presents the study on two continuous glacio-lacustrine sedimentary deposits, Laotanfang （3 597 m） and Shibantang （3 689 m） located on the southern and northern sides of Hulifang peak in Yunan, China. Environmental change indexes are constructed for each deposit, based on grain size, geochemical and pollen analysis, environmental magnetic susceptibility, and 14C dating. The study of climatic environmental change since the Holocene epoch in this region shows that the climate fluctuated at different stages during the early Holocene, that is, the climate was cool and wet during 8.4-7. 7r ka, cold and wet during 7.7-6. 5 ka, cold and dry during 6. 5-4.7 ka, cool and wet during 4.7-2. 1 ka, warm and wet during 2. 1-1.0 ka, and warmer and wet since 1 ka. These findings reflect the overlapping influences of the southwest and southeast monsoons in different times during the Holocene in the north part of southwestern China are in accord with other Holocene climate change models in this part of China.

关键词： Gongwang Mountain Holocene climatic change environmental evolution