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11.
Xuepeng Ni Zhe Cui Ning Jiang Huifang Chen Qilin Wu Anqi Ju Meifang Zhu 《材料科学技术学报》2021,77(18):169-177
The electrode materials with high pseudocapacitance can enhance the rate capability and cycling stabil-ity of lithium-ion storage devices.Herein,we fabricated MoS2 nanoflowers with ultra-large interlayer spacing on N-doped hollow multi-nanochannel carbon nanofibers(F2-MoS2/NHMCFs)as freestanding binder-free anodes for lithium-ion batteries(LIBs).The ultra-large interlayer spacing(0.78~1.11 nm)of MoS2 nanoflowers can not only reduce the internal resistance,but also increase accessible active sur-face area,which ensures the fast Li+intercalation and deintercalation.The NHMCFs with hollow and multi-nanochannel structure can accommodate the large internal strain and volume change during lithi-ation/delithiation process,it is beneficial to improving the cycling stability of LIBs.Benefiting from the above combined structure merits,the F2-MoS2/NHMCFs electrodes deliver a high rate capability 832 mA h g-1 at 10 A g-1 and ultralong cycling stability with 99.29 and 91.60%capacity retention at 10 A g-1 after 1000 and 2000 cycles,respectively.It is one of the largest capacities and best cycling stability at 10 A g-1 ever reported to date,indicating the freestanding F2-MoS2/NHMCFs electrodes have potential applications in high power density LIBs. 相似文献
12.
Gang Yan Jürgen Malzbender Shuo Fu Jürgen Peter Gross Shicheng Yu Rüdiger-A. Eichel Ruth Schwaiger 《Journal of the European Ceramic Society》2021,41(10):5240-5247
The NASICON type solid electrolyte LATP is a promising candidate for all-solid-state Li-ion batteries considering energy density and safety aspects. To ensure the performance and reliability of batteries, crack initiation and propagation within the electrolyte need to be suppressed, which requires knowledge of the fracture characteristics. In the current work, micro-pillar splitting was applied to determine the fracture toughness of LATP material for different grain orientations. The results are compared with data obtained using a conventional Vickers indentation fracture (VIF) approach. The fracture toughness obtained via micro-pillar splitting test is 0.89 ± 0.13 MPa?m1/2, which is comparable to the VIF result, and grain orientation has no significant effect on the intrinsic fracture toughness. Being a brittle ceramic material, the effect of pre-existing defects on the toughness needs to be considered. 相似文献
13.
《Ceramics International》2021,47(18):25769-25776
Lithium-sulfur battery cathodes still remain a challenge on capacity decay due to the shuttle effect even though a series of strategies have been tried. Here we report a novel matryoshka-like CuS@void@Co3O4 architecture of double micro-cubes (μ-cubes) that locks sulfur between the CuS core and the Co3O4 shell. Plenty of existing spaces between the μ-cubes suffice a high loading of sulfur and volumetric accommodation. The robust, double closed cubes configuration greatly enhances the confinement of polysulfides. In parallel, the CuS core increases the electronic conductivity and contributes to additional capacity, while the Co3O4 shell ensures a better interface activity. A high Li+ ion diffusion coefficient is obtained during the sulfur and lithium sulfide transformation. The constructed battery displays an initial capacity up to 1480 mAh g−1, and a Coulombic efficiency (CE) exceeding 99%. A capacity retention higher than 500 mAh g−1 with a CE larger than 99.8% after cycling 400 times at 0.2 C are achieved. In addition, under a temperature of −5 °C, a high capacity of 700 mAh g−1 at 0.2 C after 200 cycles is achieved, indicating a good low-temperature tolerance. 相似文献
14.
《Ceramics International》2022,48(18):26196-26205
Sea urchin-like LiAlO2@NiCoO2 hybrid composites with core-shell structure assembled with nanoneedles have been successfully fabricated through a facile hydrothermal route followed by a calcination procedure in N2 for the first time. The sea urchin-like architecture with large accessible surface can offer numerous active sites for redox reaction. The synergy of two advantages has dramatically improved the electrochemical behavior in terms of specific capacity, cycle performance and rate capability, especially at high current densities. The LiAlO2(5.0 wt%)@NiCoO2 displays charge capacities are 1309.0 and 933.6 mAh g?1 at 0.5 and 1A g?1, respectively, after 400 cycles. However, the charge capacities of bare NiCoO2 are only 562.9 and 476.7 mAh g?1 at corresponding rates. Especially, LiAlO2(5.0 wt%)@NiCoO2 preserves 358.1 mAh g?1 after 500 cycles at 2A g?1 with a capacity retention of 74%. The superior electrochemical property is related to the sea urchin-like nature and the ingenious composition design. In addition, the DFT calculation result shows that the formed stable, well-coordinated, and metallic interface between LiAlO2 and NiCoO2 are very helpful for reducing the interfacial impedance and beneficial for the improved rate capability of the materials. Therefore, such LiAlO2@NiCoO2 composites with unique morphology demonstrate a huge potential as electrode materials for Li-ion batteries. 相似文献
15.
《Ceramics International》2022,48(18):25808-25815
The harmless disposal of lead paste in the spent lead-acid batteries (LABs) remains an enormous challenge in traditional pyrometallurgical recycling. Here, we introduced a hydrometallurgical method for the recycling of the spent LABs’ waste to obtain the β-PbO as a novel zinc ion batteries (ZIBs) active material. The obtained β-PbO exhibits ultra-flat charge/discharge voltage platforms (0.21 mV/(mAh g?1)) and stable specific capacity. During the charge/discharge, the β-PbO spontaneously triggers the formation of (ZnSO4)[Zn(OH)2]3·5H2O (ZHS) micro-sheets as a surface passivation layer. Moreover, the ex-situ X-ray spectra reveal that the reversible phase transformation occurs between PbSO4 and Pb with the assistance of ZHS by adjusting the PH value on the electrode-electrolyte interface. The synergistic two-phase-reaction mechanism generates ultra-flat voltage platforms upon the charge/discharge. This “energy-saving and environment-friendly” recycling route eliminates the major source of emission of pollution particulates/gases compared to the traditional pyrometallurgical recycling, while at the same time replacing energy-consuming and environmentally detrimental processes of synthesis of current ZIBs cathodes. 相似文献
16.
《Ceramics International》2022,48(14):20220-20227
A specially designed experimental device was used in laboratory to investigate the corrosion of mullite during the calcination of Li(NixCoyMnz)O2 (LNCM) materials. The anti-corrosion tests were carried out at 1000, 1100, 1200 and 1300 °C, and characterized with X-ray diffraction and scanning electron microscopy. The influence of temperature on the interactions between mullite insulation materials and LNCM materials was determined. In addition, the high-temperature creep properties of the mullite insulation materials before and after corrosion were tested. The laboratory scale tests, thermodynamic and kinetic calculations allowed a more comprehensive understanding of the evolution of the mullite insulation materials during serving for the roasting process of LNCM materials. Through this research, it is suggested that the upgrading of the kiln lining in the lithium battery industry should select materials with excellent resistance to alkali corrosion, especially excellent resistance to Li+ corrosion. 相似文献
17.
Devendrasinh Darbar M.R. Anilkumar Vijayaraghavan Rajagopalan Indranil Bhattacharya Hendry Izaac Elim T. Ramakrishnappa F.I. Ezema Rajan Jose M.V. Reddy 《Ceramics International》2018,44(5):4630-4639
Optimization of electrodes for charge storage with appropriate processing conditions places significant challenges in the developments for high performance charge storage devices. In this article, metal cobaltite spinels of formula MCo2O4 (where M = Mn, Zn, Fe, Ni and Co) are synthesized by oxalate decomposition method followed by calcination at three typical temperatures, viz. 350, 550, and 750 °C and examined their performance variation when used as anodes in lithium ion batteries. Phase and structure of the materials are studied by powder x-ray diffraction (XRD) technique. Single phase MnCo2O4,ZnCo2O4 and Co3O4 are obtained for all different temperatures 350 °C, 550 °C and 750 °C; whereas FeCo2O4 and NiCo2O4 contained their constituent binary phases even after repeated calcination. Morphologies of the materials are studied via scanning electron microscopy (SEM): needle-shaped particles of MnCo2O4 and ZnCo2O4, submicron sized particles of FeCo2O4 and agglomerated submicron particle of NiCo2O4 are observed. Galvanostatic cycling has been conducted in the voltage range 0.005–3.0 V vs. Li at a current density of 60 mA g?1 up to 50 cycles to study their Li storage capabilities. Highest observed charge capacities are: MnCo2O4 – 365 mA h g?1 (750 °C); ZnCo2O4 – 516 mA h g?1 (550 °C); FeCo2O4 – 480 mA h g?1 (550 °C); NiCo2O4 – 384 mA h g?1 (750 °C); and Co3O4 – 675 mA h g?1 (350 °C). The Co3O4 showed the highest reversible capacity of 675 mA h g?1; the NiO present in NiCo2O4 acts as a buffer layer that results in improved cycling stability; the ZnCo2O4 with long needle-like shows good cycling stability. 相似文献
18.
The effects of titanium ion implantation on the stress corrosion cracking (SCC) behaviour of 304 austenitic stainless steel were studied. Slow strain rate tests (SSRTs) were conducted on 304 steel in air and in 5?wt-% NaCl solution. The microscopic effects of ion implantation were evaluated by Stopping and Range of Ions in Matter Procedures (SRIM). Fracture morphologies and microstructures were investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The fracture surfaces illustrate that ion implantation significantly inhibits the corrosion pits that initiate SCC. A dense passive film, which inhibits SCC, was formed during the ion implantation process. SCC initiation was restrained due to the dense dislocation nets that were generated by titanium ion implantation.Highlights
Ion implantation inhibits SCC susceptibility.
The lack of Cr at the grain boundary leads to the expansion of SCC along the grain boundary.
Implantation-induced damage leads to high-density dislocations.
The surface was amorphised due to high-density dislocations.
19.
针对高含盐氨氮废水,选择具有不同功能基团的树脂为载体,进行负载Cu2+改性制得载铜树脂并对其处理高含盐氨氮废水的性能进行研究。在筛选出最佳载铜树脂的基础上,研究pH及Na+浓度、树脂投加量、反应时间对载铜树脂处理高含盐氨氮废水效果的影响,通过对吸附氨氮前后的载铜树脂进行SEM和EDS表征分析并构建吸附动力学模型以进一步探究配位吸附的过程。结果表明,Cu2+可与螯合树脂D751稳定结合且在宽pH值下均表现出耐盐性和良好的氨氮吸附效果;在室温(25℃)、pH=11及Na+浓度4 g/L、树脂投加量8 g/L、反应时间60 min的条件下,D751载铜树脂对氨氮的去除率为34.8%。D751载铜树脂吸附氨氮后其表面出现明显的晶状结构物质,该物质可能为铜氨络合物。D751载铜树脂对高含盐氨氮的吸附符合准二级动力学模型。 相似文献
20.