The cathode-active materials LiMn2O4, LiAl0.1Mn1.9O4, and LiAl0.1Mn1.9O3.9F0.1 were synthesized by a microwave-assisted sol-gel method. The influence of different doping elements on the structural and electrochemical properties of the as-prepared samples was investigated by thermogravimetric analysis (TGA), X-ray diffraction (XRD), transmission electron microscopy (TEM), and electrochemical experiments. The results indicated that fluorine plays an important role in controlling the morphology, and the doped aluminum could enhance significantly the stability of spinel-type LiMn2O4. The initial discharge capacity of the Al3+ and F- co-substituted specimen reached 129.8 mA h/g and has a high capacity retention after 40 cycles. The outstanding electrochemical properties of LiAl0.1Mn1.9O3.9F0.1 make it a possible promising cathode material for lithium-ion batteries.
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http://dx.doi.org/10.1016/j.jcis.2005.05.013 | DOI Listing |
ACS Appl Mater Interfaces
January 2025
Key Laboratory of Advanced Ceramics and Machining Technology (Ministry of Education), and Tianjin Key Laboratory of Composite and Functional Materials, School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China.
For lithium-ion batteries, silicon monoxide is a potential anode material, but its application is limited by its relatively large irreversible capacity loss, which leads to its low initial Coulombic efficiency (ICE). In this study, we conduct a two-step reaction for the formation of silicon oxide-based materials, including a magnesiothermic reduction of SiO with Mg, followed by the solid-state lithiation of silicon oxide with LiCO. Our results demonstrate that Mg can reduce SiO to Si and form MgSiO, while LiCO reacts with SiO to form LiSiO.
View Article and Find Full Text PDFChemphyschem
January 2025
Western University, Chemistry, 1151 Richmond St, N6A5B7, London, CANADA.
Graphene quantum dots (GQDs) have emerged as promising materials for electrochemiluminescence (ECL) applications due to their unique optical and electronic properties. In this study, GQDs were synthesized via electrochemical exfoliation of graphite in a constant current density mode, enabling scalable production with controlled size and surface functionalization. GQDs-4 and GQDs-20, synthesized at applied current densities of 4 mA/cm2 and 20 mA/cm2 to the graphite electrode, respectively, were investigated on roles of surface states and exciplex dominated aggregation-induced emission (AIE) in their ECL performance.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Institute of Chemistry Chinese Academy of Sciences, CAS Key Laboratory of Molecular Recognition and Function, CHINA.
A pair of axially chiral thermally activated delayed fluorescent (TADF) enantiomers, R-TCBN-ImEtPF6 and S-TCBN-ImEtPF6, with intrinsic ionic characteristics were efficiently synthesized by introducing imidazolium hexafluorophosphate to chiral TADF unit. The TADF imidazolium salts exhibited a high photoluminescence quantum yield (PLQY) of up to 92%, a small singlet-triplet energy gap (∆EST) of 0.04 eV, as well as reversible redox properties.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Northeastern University, Corrosion and Protection Center, NO. 3-11, Wenhua Road, Heping District, Shenyang, P. R. China, Shenyang, CHINA.
The dense passive film on 316L stainless steel is the key in its corrosion resistance. Its interactions with an electroactive biofilm are critical in deciphering microbial corrosion. Herein, an in-depth investigation using genetic manipulations and addition of an exogenous electron mediator found that extracellular electron transfer (EET) mediated by the electroactive S.
View Article and Find Full Text PDFChemistry
January 2025
National & Kapodistrian University of Athens, Chemistry, Panepistimiopolis, Zografou, 15771, Athens, GREECE.
The prominence of binuclear catalysts underlines the need for the design and development of diverse bifunctional ligand frameworks that exhibit tunable electronic and structural properties. Such strategies enable metal-metal and ligand-metal cooperation towards catalytic applications, improve catalytic activity, and are essential for advancing multi-electron transfers for catalytic application. Hereby, we present the synthesis, crystal structure, and photocatalytic properties of a binuclear Ni(II) complex, [Ni2(1,10-phenanthroline)2(2-sulfidophenolate)2] (1), which crystallizes in the centrosymmetric triclinic system (P-1) showing extensive intra- and inter- non-coordinated interactions.
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