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Zinc sulfide (ZnS) nanocrystallites embedded in a conductive hybrid matrix of titanium carbide and carbon, are successfully fabricated via a facile high-energy ball-milling (HEBM) process. The structural and morphological analyses of the ZnS-TiC-C nanocomposites reveal that ZnS and TiC nanocrystallites are homogeneously distributed in an amorphous carbon matrix. Compared with ZnS-C and ZnS composites, the ZnS-TiC-C nanocomposite exhibits significantly improved electrochemical performance, delivering a highly reversible specific capacity (613 mA h g−1 over 600 cycles at 0.1 A g−1, i.e., ~85% capacity retention), excellent long-term cyclic performance (545 mA h g−1 and 467 mA h g−1 at 0.5 A g−1 and 1 A g−1, respectively, after 600 cycles), and good rate capability at 10 A g−1 (69% capacity retention at 0.1 A g−1). The electrochemical performance is significantly improved, primarily owing to the presence of conductive hybrid matrix of titanium carbide and amorphous carbon in the ZnS-TiC-C nanocomposites. The matrix not only provides high conductivity but also acts as a mechanical buffering matrix preventing huge volume changes during prolonged cycling. The lithiation/delithiation mechanisms of the ZnS-TiC-C electrodes are examined via ex situ X-ray diffraction (XRD) analysis. Furthermore, to investigate the practical application of the ZnS-TiC-C nanocomposite, a coin-type full cell consisting of a ZnS-TiC-C anode and a LiFePO4–graphite cathode is assembled and characterized. The cell exhibits excellent cyclic stability up to 200 cycles and a good rate performance. This study clearly demonstrates that the ZnS-TiC-C nanocomposite can be a promising negative electrode material for the next-generation lithium-ion batteries.

A nanostructured ZnTe–TiO2–C composite is synthesized, via a two-step high-energy mechanical milling process, for use as a new promising anode material in Li-ion batteries (LIBs). X-ray diffraction and X-ray photoelectron spectroscopy results confirm the successful formation of ZnTe alloy and rutile TiO2 phases in the composites using ZnO, Te, Ti, and C as the starting materials. Scanning electron microscopy, transmission electron microscopy, and energy dispersive X-ray spectroscopy mapping measurements further reveal that ZnTe and TiO2 nanocrystals are uniformly dispersed in an amorphous carbon matrix. The electrochemical performances of ZnTe–TiO2–C and other control samples were investigated. Compared to ZnTe–TiO2 and ZnTe-C composites, the ZnTe– TiO2–C nanocomposite exhibits better performance, thereby delivering a high reversible capacity of 561 mAh g−1 over 100 cycles and high rate capability at a high current density of 5 A g−1 (79% capacity retention of its capacity at 0.1 A g−1). Furthermore, the long-term cyclic performance of ZnTe–TiO2–C at a current density of 0.5 A g−1 shows excellent reversible capacity of 528 mAh g−1 after 600 cycles. This improvement can be attributed to the presence of a TiO2-C hybrid matrix, which acts as a buffering matrix that effectively mitigates the large volume changes of active ZnTe during repeated cycling. Overall, the ZnTe–TiO2–C nanocomposite is a potential candidate for high-performance anode materials in LIBs.