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Abstract A novel 3D porous CoP@C-CNTs composite with CNTs threaded CoP@C nanocubes is rationally designed and demonstrated as a promising anode for lithium-ion battery. The CoP@C-CNTs composite displays high surface area and abundant pores resulted from the pyrolysis of metal-organic frameworks (MOFs). CoP nanoparticles are well encapsulated in MOFs-derived carbon nanocubes, which can effectively accommodate the volume change of active CoP during charge/discharge processes. Besides, the N/P co-doped feature induced in-situ in the synthesis process helps to improve the electrical conductivity. Moreover, the presence of intertwined CNTs network threaded CoP@C nanocubes is the vital part for rapid electron transportation within the whole electrode. As a result, the CoP@C-CNTs electrode exhibits a high initial discharge capacity of 1254 mAh g−1 at a current density of 0.1 A g−1, and an outstanding rate performance (532 mAh g−1 at current densities of 5 A g−1), as well as excellent cycling stability with a capacity fade rate of ∼0.02% per cycle over 500 cycles at the current density of 2 A g−1. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Biomass materials show great potential in replacing mineral carbon source to fabricate novel high-energy electrode materials. However, it is greatly challenging to prepare core-shell carbon hybrid materials with homogeneous dispersion and high tap density features from biomass since biomass-carbons often exhibit blocky structure. Herein, we facilely fabricate the core-shell microcubes of MnO@C (CCM, average size of ∼5 μm) composite with high tap density of 2.17 g cm−3 using natural agaric as raw materials through simple hydrothermal treatments and calcination process. And the formation mechanism of core-shell microcube structures is analysized by the phase separator theory. It is found that the high-tap-density CCM composite with the stable porous carbon shell (∼1 μm) greatly contributes to accommodate the volume change of MnO active material during lithiation/delithiation process and enable rapid electron/ion transport. As expected, the CCM electrode offers a superhigh volumetric capacity of 1628.7 mAh cm−3, the high reversible capacity (1147 mAh g−1 at 0.1 A g−1), outstanding rate performance (552 mAh g−1 at 2 A g−1) and cycling stability (802 mAh g−1 after 950 cycles at 1 A g−1). We believe that the facile and low-cost biomass-intervened strategy is feasible to fabricate practical core-shell structured metal oxide@carbon composites for efficient electrochemical energy storage. Core-shell MnO@C microcubes obtained from a biomass-intervened strategy are investigated as LIB anode, and shows high specific volumetric capacity, good cycle stability and rate capability. Image 1 • A simple agaric-intervened strategy for core-shell MnO@C microcubes. • The uniform size of ∼5 μm and stable porous carbon shell (∼1 μm). • The composite shows high-tap-density (2.17 g cm−3). • To accommodate the volume change of MnO during lithiation/delithiation. • Superhigh specific volumetric capacity of 1628.7 mAh cm−3 at 0.1 A g−1 • Excellent cycling stability (802 mAh g−1 after 950 cycles at 1 g−1). [ABSTRACT FROM AUTHOR]