Li3Co2SbO6 is found to adopt two highly distinct structural forms: a pseudohexagonal (monoclinic C2/m) layered O3-LiCoO2 type phase with “honeycomb” 2:1 ordering of Co and Sb, and an orthorhombic Fddd phase, isostructural with Li3Co2TaO6 but with the addition of significant Li/Co ordering. Pure samples of both phases can be obtained by conventional solid-state synthesis via a precursor route using Li3SbO4 and CoO, by controlling particle size, initial lithium excess, and reaction time. Both phases show relatively poor performance as lithium-ion battery cathode materials in their as-made states, but complex and interesting low-temperature magnetic properties. The honeycomb phase is the first of its type to show A-type antiferromagnetic order (ferromagnetic planes, antiferromagnetically coupled) below T N = 14 K. Isothermal magnetization and in-field neutron diffraction below T N show clear evidence for a metamagnetic transition at H ≈ 0.7 T to three-dimensional ferromagnetic order. The orthorhombic phase orders antiferromagnetically below T N = 112 K and then undergoes two more transitions at 80 and 60 K. Neutron diffraction data show that the ground state is incommensurate.

A 2-D coordination framework, (NEt4)2[Fe2(fan)3] (1·5­(acetone); H2fan = 3,6-difluoro-2,5-dihydroxy-1,4-benzoquinone), was synthesized and structurally characterized. The compound is structurally analogous to a formerly elucidated framework, (NEt4)2[Fe2(can)3] (H2can = 3,6-dichloro-2,5-dihydroxy-1,4-benzoquinone), and adopts a 2-D (6,3) topology with the symmetrical stacking of [Fe2(fan)3]2– sheets that are held in position by the NEt4 + cations between the sheets. The investigation of the dc and ac magnetic properties of 1·5­(acetone) revealed ferromagnetic ordering behavior and slow magnetization relaxation, as evinced from ac susceptibility measurements. Furthermore, the exposure of 1·5­(acetone) to air led to the formation of a heptahydrate 1·7H 2 O which displayed distinct magnetic properties. The study of the redox state and extent of delocalization in 1·5­(acetone) was undertaken via crystallography, in combination with Mössbauer and vis–NIR spectroscopy, to reveal the mixed-valence and delocalized nature of the as-synthesized material. As a result, the conductivity studies conducted on a pressed pellet showed a relatively high conductivity of 1.8 × 10–2 S cm–1 (300 K). In order to compare structurally related anilate-based structures, a relationship among the redox state, spectroscopic properties, and electronic properties was elucidated in this work. A preliminary investigation of 1·5­(acetone) as a candidate anode material in lithium ion batteries revealed a high reversible capacity of 676.6 mAh g–1 and high capacity retention.

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A templating method is developed to produce porous nanocrystalline anatase materials for negative electrodes in lithium‐ion batteries (LIBs). Amphiphilic diblock copolymers are used to generate template films with phase‐separated internal structure. Subsequent swelling with acidified titanium(IV) bis(ammonium lactato) dihydroxide (TALH) solution yielded structured hybrid films. Upon heating, the formation of TiO2 nanocrystals is induced, resulting in a three‐dimensional mesoporous structure directed by the bulk morphology of the polymer template. In comparison to commercial nanosized anatase, the structured anatase shows significant performance improvements in lithium‐ion coin cell batteries in terms of capacity, stability, and rate capability. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1890–1896

Micro-sized porous LiMnPO4 nanoflakes were synthesized using a novel precursor. Porous LiMnPO4–C nanoflakes present promising electrochemical properties, especially superior rate capability. The methodology described in this work is facile and would be helpful for practical applications of the LiMnPO4 cathode.

The composite of hard carbon and nano-graphite (HCNG) is prepared by the pyrolysis of sucrose with the catalysis agent. In HCNG, nano graphite particles are imbedded in hard carbon. HCNG is used as the anode material for lithium ion battery and shows a low and flat discharge platform, which is similar to that of graphite. HCNG displays much higher capacity (450 mAh/g) than that of commercial graphite (CG) anode (360 mAh/g). Besides, much better rate performance is obtained with HCNG than CG. It is supposed that the increased capacity rises from the Li ion storage on the surface of the graphite nanocrystals embedded in amorphous carbon matrix. The improvement of the rate capability results from the small particle size of graphite phase and more ion transportation paths supplied by the amorphous carbon.

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particles consisting of nanopores are prepared using MnPO 4 ?H 2 O as the precursor. The nanopores were formed by the thermal decomposition of the precursor. Fe doping and carbon coating were realized in one step during the heat treatment. Polyethylene glycol (PEG) was used as the carbon source and milled with the other precursor to form the carbon coating throughout the whole micrometer particle sample. Due to the short ion transportation distance of the active materials caused by the nanopores, the composite displays high discharge capacity, and good rate capability and cycle stability.With only 4% carbon, the capacity of LiMn 0.7 Fe 0.3 PO 4 -C reaches 132 mA h g 21 under the galvanostatic charge-discharge mode, and 140 mA h g 21 under the constant current-constant voltage (CC-CV) charge mode.