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Flexible High Energy Density sodium Dual-ion Battery with Long Cycle life

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Energy & Environmental Materials 2022年第4期5卷 1285-1293页

作者： Yongpeng Li Qun Guan Jianli Cheng Bin Wang Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China Institute of Fundamental and Frontiers Sciences Yangtze Delta Region Institute(Huzhou)University of Electronic Sciences and Technology of ChinaChengdu 611731China

Flexible fiber-shaped sodium dual-ion batteries(FSDIBS)as a proof of concept are fabricated by using the hierarchical ReS_(2) nanosheets anchored on the carbon nanotube(ReS_(2)@CNT)fiber as anode and graphite on the CNT as *** to large interlayer spacing and weak layer coupling force of the ReS_(2) nanosheets and the anion accommodation of the graphite combined with good flexibility of the CNT fiber,the FSDIBS demonstrate outstanding electrochemical performances with high working voltage and high specific volumetric energy density,durable cycling life,and good *** FSDIBS show a specific discharge capacity of 97.8 mAh cm^(−3) at a current density of 630 mA cm^(−3) and high specific energy density of 25.12 mWh cm^(−3)(based on the whole volume of the two electrodes)and superb stability with a capacity retention of 91.8%even after bending for 2100 ***,a series of ex situ/in situ characterizations are verified that the reversible shuttles of the Na^(+) cations and PF_(6)^(-) anions between the anode and cathode are simultaneously occurred during the charge/discharge process.

关键词： dual-ion batteries fiber-shaped flexibility ReS_(2) sodium ions

Layered Birnessite Cathode with a Displacement/Intercalation Mechanism for High-Performance Aqueous Zinc-Ion Batteries

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Nano-Micro Letters 2020年第4期12卷 137-151页

作者： Xian‑Zhi Zhai Jin Qu Shu‑Meng Hao Ya‑Qiong Jing Wei Chang Juan Wang Wei Li Yasmine Abdelkrim Hongfu Yuan Zhong‑Zhen Yu State Key Laboratory of Organic‑Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Mn-based rechargeable aqueous zinc-ion batteries(ZIBs)are highly promising because of their high operating voltages,attractive energy densities,and ***,the electrochemical performances of Mn-based cathodes usually suffer from their serious structure transformation upon charge/discharge ***,we report a layered sodium-ion/crystal water co-intercalated Birnessite cathode with the formula of Na0.55Mn2O4·0.57H2O(NMOH)for high-performance aqueous ZIBs.A displacement/intercalation electrochemical mechanism was confirmed in the Mn-based cathode for the first ***+and crystal water enlarge the interlayer distance to enhance the insertion of Zn^2+,and some sodium ions are replaced with Zn^2+ in the first cycle to further stabilize the layered structure for subsequent reversible Zn^2+/H^+ insertion/extraction,resulting in exceptional specific capacities and satisfactory structural ***,a pseudo-capacitance derived from the surface-adsorbed Na^+ also contributes to the electrochemical *** NMOH cathode not only delivers high reversible capacities of 389.8 and 87.1 mA h g^−1 at current densities of 200 and 1500 mA g^−1,respectively,but also maintains a good long-cycling performance of 201.6 mA h g^−1 at a high current density of 500 mA g^−1 after 400 cycles,which makes the NMOH cathode competitive for practical applications.

关键词： Zinc-ion batteries Birnessite sodium ions Layered structure Crystal water

Corrections for downhole NMR logging

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Petroleum Science 2012年第1期9卷 46-52页

作者： Hu Haitao Xiao Lizhi Wu Xiling State Key Laboratory of Petroleum Resource and Prospecting China University of PetroleumBeijing 102249China

Nuclear magnetic resonance logging （NMR） is an open well logging method. Drilling mud resistivity, formation resistivity and sodium ions influence its radio frequency （RF） field strength and NMR logging signals. Research on these effects can provide an important basis for NMR logging data acquisition and interpretation. Three models, water-based drilling mud--water bearing formation, water- based drilling mud--oil bearing formation, oil-based drilling mud--water bearing formation, were studied by finite element method numerical simulation. The influences of drilling mud resistivity and formation resistivity on the NMR logging tool RF field and the influences of sodium ions on the NMR logging signals were simulated numerically. On the basis of analysis, RF field correction and sodium ion correction formulae were proposed and their application range was also discussed. The results indicate that when drilling mud resistivity and formation resistivity are 0.02 Ω·m and 0.2 Ω·m respectively, the attenuation index of centric NMR logging tool is 8.9% and 9.47% respectively. The RF field of an eccentric NMR logging tool is affected mainly by formation resistivity. When formation resistivity is 0.1 Ω·m, the attenuation index is 17.5%. For centric NMR logging tools, the signals coming from sodium ions can be up to 31.8% of total signal. Suggestions are proposed for further research into NMR logging tool correction method and response characteristics.

关键词： NMR logging finite element method RF field NMR signal formation resistivity sodium ions

Changes of intracellular Na^+ concentration in erythrocytes caused by pulsed electrical field

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Science China(Life Sciences) 1997年第5期40卷 488-495页

作者：张锦珠孙彤陈雅周淑华陈云俊庞素珍 Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China

Changes of sodium ionic concentration of human erythrocytes applied to pulsed electrical field (PEF) were studied by using shift reagent and NMR spectroscopy. The results show that the concentration of intracellular Na+ increases with the increasing intensity of PEF when the erythrocytes are applied to PEF with higher intensities. The relationship between intracellular Na concentrations and the intensities of PEF does not follow linear or exponen-tial behavior. As the intensities increase, the intracellular Na+ concentrations increase even faster by an exponential curve. However under effects of PEF at lower intensities, intracellular Na+ concentration decreases. Ouabain can in-hibit the decrease of intracellular Na concentration, and the inhibition increases with the increasing concentration of ouabain, suggesting that Na , K -ATPase on cell membrane can be activated by PEF at lower intensities. Direct measurement of activities of the enzyme by using Malachite green method has confirmed this observation. Cell perme-abilities to ions, activation of enzymes by electrical fields and transmission of physical signals like PEF across cell mem-branes are discussed.

关键词： pulsed electrical field sodium ions Na^+ K^+-ATPase ^(23)Na-NMR crythrocytes erythrocyte ghosts.