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Abstract Li 2 MnSiO 4 is considered as a promising cathode candidate for high energy density Lithium-ion batteries (LIBs), due to its high theoretical capacity, favorable working potential as well as the low-cost and non-toxic nature of manganese element. However, it suffers from low capacity utilization and inferior cycling performance, due to the structural rearrangement upon cycling, phase impurities and manganese dissolution. To address these issues, nanostructure construction and carbon coating proves to be effective approach. In this work, we introduce an in situ template synthesis of a phase-pure Li 2 MnSiO 4 @C (MP-LMS@C) composite, which exhibits unique mesoporous morphology with nanosized Li 2 MnSiO 4 granules homogenously encapsulated in the interconnected carbon networks. Such unique Li 2 MnSiO 4 @C structure not only facilitates electron conduction and Li+ transport, but also suppresses the manganese dissolution, as a result, the mesoporous Li 2 MnSiO 4 @C cathode exhibits greatly improved electrochemical performance, with a high specific capacity of 230 mAh g−1, good rate capability and superior capacity retention of 81% over 100 cycles. [ABSTRACT FROM AUTHOR]

Promoting oxygen reduction and evolution reactions using effective catalysts hold broad significance for clean energy utilization. In this work, hollow N-doped carbon networks (N-CNs) were fabricated via interfacial dehalogenation of polyvinyl dichloride (PVDC) on 2D CoAl-layered double hydroxide (LDH) with the presence of N source and used as efficient bifunctional catalysts. BET results revealed that as-made N-CNs had very large specific surface area (SSA, 550.4 m 2 g −1 for 900 °C-annealed N-CN (N-CN9)) and abundant pore hierarchy. Additionally, interconnected graphitic carbon walls, forming separated cells, can ensure high electrical conductivity, which were formed after acid-leaching of metallic components. Remarkably, N-CN9 showed excellent bifunctional activities towards oxygen reduction and evolution reactions. Moreover, N-CN9 assembled Zn-air battery (ZAB) exhibited an operating voltage of 1.35 V under applied current density of 1.0 mA cm −2 , which is highly comparable to that of PtRu/C catalyst. Moreover, due to the pore hierarchy and large SSA, N-CN9-ZAB possessed much better rate capability and cycling stability than that of PtRu/C-ZAB. [ABSTRACT FROM AUTHOR]

Abstract: A polymer carbonization route was designed to synthesis carbon network-supported Fe3O4@C composites. The Fe3O4 nanoparticles with an average of ∼200nm were uniformly wrapped up in this novel carbon network. As an anode material for rechargeable lithium-ion batteries, the Fe3O4@C composites present attractive properties with a high specific capacity of 730mAhg−1 at 2C after 300 cycles. The novel carbon network plays a key role in enhancing the electrochemical performance of the composites. [Copyright &y& Elsevier]