The lithium (Li)-metal anode is deemed as the “holy gray” of the next-generation Li-metal system because of its high theoretical specific capacity, minimal energy density, and lowest standard electrode potential. Nevertheless, its commercial application has been limited by the large volume variation during charge and discharge, the unstable interface between the Li metal and electrolyte, and uneven deposition of Li. Herein, we present a 3D host (Cu) with lithiophilic matrix (CuO and SnO2) in situ modification via a facile ammonia oxidation method to serve as a current collector for the Li-metal anode. The 3D Cu host embellished by CuO and SnO2 is abbreviated as 3D CSCC. By increasing interfacial activity, lowering the nucleation barrier, and accommodating changes in volume of the Li metal, the 3D CSCC electrode effectively demonstrates a homogeneous and dendrite-free deposition morphology with an excellent cycling performance up to 3000 h at a 1.0 mA cm–2 current density. Additionally, the full cells paired with Li@3D CSCC anodes and LiCoO2 cathodes show good capacity retention performance at 0.2 C.

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Transition-metal oxides are attracting considerable attention as anodes for lithium-ion batteries because of their high reversible capacities. However, the drastic volume change and inferior electrical conductivity greatly retard their widespread applications in lithium-ion batteries. Herein, three-dimensional nanoporous composites of CoO x (CoO and Co 3 O 4 ) quantum dots and zeolitic imidazolate framework-67-derived carbon are fabricated by a precipitation method. The carbon prepared by carbonization of zeolitic imidazolate framework-67 can greatly enhance the electrical conductivity of the composite anodes. CoO x quantum dots anchored firmly on zeolitic imidazolate framework-67-derived carbon can effectively inhibit the aggregation and volume change of CoO x quantum dots during lithiation/delithiation processes. The nanoporous structure can shorten the ion diffusion paths and maintain the structural integrity upon cycling. Meanwhile, kinetics analysis reveals that a capacitance mechanism dominates the lithium storage capacity, which can greatly enhance the electrochemical performance. The composite anodes show a high discharge capacity of 1873 mAh g –1 after 200 cycles at 200 mA g –1 , ultralong cycle life (1246 mAh g –1 after 900 cycles at 1000 mA g –1 ), and improved rate performance. This work may provide guidelines for preparing cobalt oxide-based anodes for LIBs.

Silicon (Si) is regarded as one of the most promising anode materials for lithium-ion batteries (LIBs) due to its high capacity and low working voltage. However, dramatic volume expansion and inferior electrical conductivity greatly impede the commercial use of Si anodes. Herein, we design and synthesize a novel nanocomposite of Si nanosphere coated by carbon (Si@C) and hollow porous Co 9 S 8 /C polyhedron (Si@CÀ Co 9 S 8 /C). The hollow porous Co 9 S 8 /C derived from Co-based zeolitic imidazolate framework can serve as a buffering matrix to accommodate the volume expansion of Si, which is beneficial to improve the cycle performance. The vast conductive carbon layer originated from Co 9 S 8 /C and Si@C plays a key role in accelerating the electron transfer and lithium ion transport kinetics, which can significantly enhance the rate performance. As a result, the Si@CÀ Co 9 S 8 /C anodes deliver stable cycle performance with a reversible capacity of 1399 mA h g À 1 after 200 cycles at 100 mA g À 1 , improved rate performance and high Coulombic efficiency. This simple route sheds light on designing Si-based composites for LIBs anodes.

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Nickel sulfides (NS) occupy a vital position in the fields of catalysis and energy storage by virtue of their outstanding functional properties. Currently, NS are usually synthesized in solid-state sulfidation...