Search

Abstract: As an anode material for lithium-ion batteries (LIBs), silicon offers among the highest theoretical storage capacity, but is known to suffer from large structural changes and capacity fading during electrochemical cycling. Nanocomposites of silicon with carbon provide a potential material platform for resolving this problem. We report a spray-pyrolysis approach for synthesizing amorphous silicon–carbon nanocomposites from organic silane precursors. Elemental mapping shows that the amorphous silicon is uniformly dispersed in the carbon matrix. When evaluated as anode materials in LIBs, the materials exhibit highly, stable performance and excellent Coulombic efficiency for more than 150 charge discharge cycles at a charging rate of 1A/g. Post-mortem analysis indicates that the structure of the Si–C composite is retained after extended electrochemical cycling, confirming the hypothesis that better mechanical buffering is obtained when amorphous Si is embedded in a carbon matrix. [Copyright &y& Elsevier]

Abstract: A novel C/Co composite with Co nanoparticles embedded in carbon matrix is synthesized firstly by pyrolysis of polymeric cobalt phthalocyanine (PcCo) at 700°C in argon atmosphere. This composite is investigated as an anode material for lithium ion batteries, indicating high tap density and excellent electrochemical performance. The C/Co electrode can retain a higher reversible capacity of over 600mAhg−1 at a current of 50mAg−1 after 40cycles and shows better rate capability and less hysteresis in comparison to carbon not containing Co. The significant improvement is attributed to the Co nanoparticles grown in-situ reaction with catalytic activity and high electrical conductivity. [Copyright &y& Elsevier]

Abstract: A unique ordered mesoporous Sn–C composite with Sn nanoparticles confined in carbon nanorods was prepared using SBA-15 as the template. This composite was employed as the anode material of Li-ion batteries, delivering excellent electrochemical properties of high reversible lithium storage capacity (554 mAh g−1 after 200 cycles) and great rate capability (as high as 5000mA g−1). [Copyright &y& Elsevier]