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In this work, we demonstrated an accessible and facile method to prepare hierarchically porous carbon (HPC)/Co 3 O 4 nanocomposites (HPCC). Biomaterials-derived HPC was used as the appropriate carrier to load Co 3 O 4 nanoparticles due to its hierarchically porous structure and high surface area of 163 m 2 g −1 . The HPCC nanocomposites were used as an anode material for lithium-ion batteries (LIBs) and showed good electrochemical performance, delivering an initial discharge of 1566 and charge capacity of 1314 mA h g −1 with a initial coulombic efficiency of 83.9%. Additionally, it could still maintain a high reversible capacity of 1215 mA h g −1 after 100 cycles at a specific current of 100 mA g −1 , which is much better than that of HPC, and Co 3 O 4 and some Co 3 O 4 -based nanocomposites. The good electrochemical performance was mainly attributed to the good distribution of small Co 3 O 4 on HPC, the high surface area and hierarchical pores of HPC to effectively load a number of small Co 3 O 4 , alleviate the severe volume expansion during cycling and improve the electrical conductivity of nanocomposites, and the synergistic effects from the HPC and Co 3 O 4 . Therefore, the HPCC nanocomposites were expected to be an advanced anode material for LIBs. [ABSTRACT FROM AUTHOR]

Hollow multicomponent transition metal oxide nanostructures have caused extensive attention due to their enhanced performances in lithium-ion batteries (LIBs). Herein, a hybrid of multicomponent 3NiO·2Ni 3/2 Co 1/2 ZnO 4 nanocomposite with porous hollow dodecahedron nanostructures (3NiO·2Ni 3/2 Co 1/2 ZnO 4 -HD) was fabricated by carbonization of NiCoZn-layered double hydroxides which were derived from multimetallic zeolitic imidazolate frameworks (Zn/Co-ZIFs) as both self-sacrificial template and precursors. The 3NiO·2Ni 3/2 Co 1/2 ZnO 4 -HD nanocomposites were carefully characterized by various techniques including scanning electron microscopy, X-ray powder diffraction, X-ray photoelectron spectroscopy, thermogravimetric analysis, N 2 adsorption/desorption, transmission electron microscopy, Four-Point Probes and electrochemical techniques. When the 3NiO·2Ni 3/2 Co 1/2 ZnO 4 -HD nanocomposites were acted as anode materials for LIBs, a capacity of about 1337 mA h g −1 could be obtained after 100 cycles. The improved electrochemical performances might originate from synergistic effect of multicomponents, enhanced electrical conductivity and porous hollow dodecahedron nanostructures which could effectively alleviate volume deformation in the process of discharge/charge, accelerate mass transfer and increase the active sites for Li + storage. [ABSTRACT FROM AUTHOR]