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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]

Hollow carbon spheres (HCSs) materials have been investigated extensively for various applications in energy storage, catalysis, electrochemical conversion. At present, template method using liquid or gaseous carbon sources is the dominant synthetic route for HCSs. Herein, HCSs with high nitrogen doping levels are synthesized by employing graphitic carbon nitride (g-C 3 N 4) solid precursor as carbon and nitrogen sources with the presence of Zn templates. The successful synthesis of N-doped HCSs using solid g-C 3 N 4 precursor is confirmed by a series of characterization technologies. Serving as the anode materials in lithium ions batteries, promising lithium ions storage performances are obtained for the resultant N-doped HCSs. Brilliant specific capacities of 1506.6 mAh g−1 at 0.1 A g−1 and 519.2 mAh g−1 at 5 A g−1 are recorded after 360 cycles. The promising lithium ion storage performances of the N-doped HCSs are ascribed to the unique hollow structure with large surface area, suitable nitrogen doping level and large inner pore volume. The presented work provides a new route to synthesize HCSs or heteroatoms doped HCSs materials using solid carbon sources. • N-doped HCSs was synthesized using solid precursor with presence of Zn template. • Tunable N-doping levels from 21.47 to 33.32 at.% were realized for N-doped HCSs. • The Zn template was revealed to play the extra role of reduction denitrogenation. • N-doped HCSs delivers high specific capacity of 1506.6 mAh g−1 as LIBs anode. [ABSTRACT FROM AUTHOR]