Lithium storage properties of MOF-on-MOF derived In2O3/Co3O4 heterojunction with ‘‘chocolate-bar’’ structure

Lithium-ion batteries (LIBs) have become indispensable in modern society, powering a wide range of portable electronics and electric vehicles. Nevertheless, the development of high-performance anode materials remains hindered by challenges such as limited capacity and severe volume fluctuations during lithiation/delithiation. Here, we report a rationally designed MOF-on-MOF derived In₂O₃/Co₃O₄ heterojunction featuring a unique hollow “chocolate-bar” architecture. This structure not only offers a high specific surface area of 1174 m²/g and abundant electroactive sites, but also effectively accommodates volume changes and preserves structural integrity during cycling. Benefiting from the strong synergistic coupling at the In₂O₃–Co₃O₄ interface, as confirmed by DFT calculations, the heterojunction exhibits enhanced electronic conductivity and reduced lithium-ion diffusion barriers. As a result, the In₂O₃/Co₃O₄ electrode delivers a high reversible capacity of 920.5 mAh/g at 0.5C and retains 710.85 mAh/g at 1C with the CE exceeding 99.45 % over 500 cycles. By combining practical and theoretical design techniques, this study demonstrates the prospective of MOF-on-MOF derived heterostructures as a viable platform for creating next generation LIB anodes.