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MOF-derived XMn 2 O 4 (X = Zn, Co, Cu, Ni) nanomaterials achieve superior electrochemical performance for lithium storage. [Display omitted] • Two methods are proposed for the synthesis of XMn 2 O 4 (X = Zn, Co, Cu, Ni). • MOF-derived anodes exhibit excellent electrochemical capabilities compared with the ones obtained by simple coprecipitation. • Lithium storage capacity and rate performance of XMn 2 O 4 is best when X = Zn. • DFT calculations are performed to demonstrate that ZnMn 2 O 4 as an anode material is conducive to the diffusion of Li+. Bimetallic spinel transition metal oxides play a major part in actualizing eco-friendly electrochemical energy storage systems (ESSs). However, structural precariousness and low electrochemical capacitance restrict their actual implementation in lithium-ion batteries (LIBs). To address these demerits, the sacrificial template approach has been considered as a prospective way to strengthen electrochemical stability and rate performance. Herein, metal-organic frameworks (MOFs) derived XMn 2 O 4 -BDC (H 2 BDC = 1,4-dicarboxybenzene, X = Zn, Co, Cu, Ni) are prepared by a hydrothermal approach in order to discover the effects of various metal cations on the electrochemical performance. Among them, ZnMn 2 O 4 -BDC displays best electrochemical properties (1321.5 mAh g−1 at the current density of 0.1 A g−1 after 300 cycles) and high efficiency with accelerated Li+ diffusivity. Density functional theory (DFT) calculations confirm the ZnMn 2 O 4 possesses the weakest adsorption energy on Li+ with a minimized value of −0.92 eV. In comparison with other XMn 2 O 4 through traditional fabrication method, MOF-derived XMn 2 O 4 -BDC possesses a higher number of Li+ transport channels and better electric conductivity. This tactic provides a feasible and effective method for preparing bimetallic transition metal oxides and enhances energy storage applications. [ABSTRACT FROM AUTHOR]

SiO x is proposed as one of the most promising high-performance anodes for its favorable capacity and stable lithium insertion/extraction electric potential, however its effective commercial application still faces giant challenge. To overcome poor electrical conductivity and huge volume effect of silicon oxide-based material, we adopt a valid strategy to synthesis the SiO x nanosphere double-wrapped by MoS 2 and multi-walled carbon nanotubes (CNTs) as anode material. The influences of MoS 2 and CNTs on the structure, morphology and electrochemical performances of nanohybrid are probed detailly by transmission electron microscopy, X-ray photoelectron spectroscopy and charge-discharge measurements. The results show that as-prepared nanohybrids release a steady reversible capacity of 798 mAh g−1 with high capacity retention of 81.4% at 500 mA g−1 after 300 cycles. The outstanding electrochemical properties can be ascribed to the facts that the hollow mesoporous structure affords ample buffer space and the introduction of MoS 2 with a two-dimensional layered structure can provide more exposed active-sites for lithium adsorption, as well as the CNTs wrapping can form a favorable conductivity matrix, endowing the nanocomposites with great structural stability. Accordingly, this new structure design by means of a heterogeneous dual-wrapped architecture develops a significant strategy for the development of high-performance SiO x -based anode materials. Unlabelled Image • Heterogeneous dual-wrapped architecture of SiO x /MoS 2 -CNTs is successfully prepared. • The hollow structure shortens the transportation of Li+/e− and offers buffer space. • Wrapping MoS 2 can own more exposed active sites for promoting transport of Li+/e−. • The conductive twining CNTs form a favorable conductivity framework. • The material presents excellent cycling performance and rate capability. [ABSTRACT FROM AUTHOR]