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A dual interface SiO x /C composite is prepared through a novel, facial, one-step route by redox reaction of organic carbon with silica precursor, using tetraethyl orthosilicate (TEOS) and sucrose as raw material, in which sucrose acts as both a reductant and coated carbon. HRTEM indicates that the composite has a dual interface structure with carbon coating layer and intermediate layer. Crystalline Si approximately 3 nm–20 nm in size is dispersed in amorphous silicon oxide matrix. The SiO x /C is utilized in LIB as anode material and exhibits a high reversible specific capacity of 755 mA h g−1 after 300 cycles at 100 mA g−1 with capacity retention about 91%. Such outstanding cycling stability can be ascribed to the intermediate layer and carbon scaffold, which serve as a buffering to relieve volume change of produced Si upon cycles. • SiO x /C composite with dual interface structure is fabricated by a facial, one-pot synthesis method. • Dual interface structure provides a strong buffering for volume change of SiO x /C. • The dual interface SiO x /C shows high capacity and outstanding cycling performance. • Structure and electrochemical performance analysis of SiO x /C are studied in detail. [ABSTRACT FROM AUTHOR]

CuO–Cu 2 O/graphene composite has been successfully prepared by the combination of a microwave-assisted process and subsequent annealing. X-ray diffraction and electron microscopy reveals that copper oxide nanospheres with a size of 120–200 nm are uniformly anchored on graphene nanosheets. The copper oxide nanospheres are composed of numerous CuO and Cu 2 O nanocrystals of ∼10 nm. These nanospheres are hollow and the thickness of the shells is around 50–70 nm. The CuO–Cu 2 O/graphene composite shows a highly reversible capacity and excellent rate performance as anode for Li-ion battery. The reversible capacity of the composite retains 487 mA h g −1 after 60 cycles at 200 mA g −1 . Even when cycled at various rate (200, 500, 1000, 2000, 5000 mA g −1 ) for 60 cycles, the capacity can recover to 520 mA h g −1 at the current of 200 mA g −1 . The enhanced electrochemical performances are ascribed to the hollow spherical architectures, excellent conductivity of graphene sheets, and possible synergistic effects between CuO, Cu 2 O and graphene that enhance the intrinsic properties of each component. [ABSTRACT FROM AUTHOR]

To solve the poor conductivity of the anode materials for lithium-ion batteries (LIBs) and enhance the lithium-ion transportation, silver-incorporated Fe 2 O 3 -C (Fe 2 O 3 -C-Ag) porous microcubes were fabricated through polydopamine reduction of AgNO 3 and subsequently high temperature carbonization process using the prussian blue as template. Interestingly, polydopamine not only served as reducing agent for Ag + but also as carbon source in this work, which avoid adding additional reduction agent and high temperature, resulting in a simple and mild reduction condition. When Fe 2 O 3 -C-Ag microcubes were performed as anode materials for lithium-ion batteries (LIBs), the hybrid materials behaved pretty electrochemical properties. The introduction of noble metal (Ag) and carbon to transition metal oxides was an innovative method to form anode materials for lithium-ion batteries (LIBs), which can effectively increase the conductivity of the electrode materials as well as inhibit the volume expansion during cycling. With 10% (wt%) Ag nanoparticles coating in the hybrid composites, the Fe 2 O 3 -C-Ag-10 microcubes exhibit good reversible capacities and pretty cyclic performance (858 mAh g −1 after 200 cycles at 100 mA g −1 ). This novel approach can provide a potential idea to design advanced anode materials for LIBs. [ABSTRACT FROM AUTHOR]