MOFs nanosheets derived porous metal oxide-coated three-dimensional substrates for lithium-ion battery applications

Porous nanosheet-structured materials have received great attention because of their promising applications in energy field. Construction of porous metal oxides nanosheets on three-dimensional (3D) electro-conductive substrates is an effective way to further enhance electrochemical performance of energy storage devices. Herein, porous transition metal oxides (i.e. ZnO, Co3O4) nanosheets derived from MOFs coated 3D substrates (i.e. 3D nickel foam, carbon fiber) are successfully synthesized by a facile liquid -phase deposition method with subsequent calcination. The growth mechanism of MOFs with nanosheet morphology coated 3D substrates is investigated. As a proof of concept application, the Co304/3DNF hybrid, possessing the advantages of porous nanosheet-structured and 3D electro-conductive substrates, is used as a binder-free anode material for lithium-ion battery, which exhibits high rate capability and long-term cyclic stability. High discharge capacities of 1135, 1268, 1226, 1130, 923, 751, and 543 mA h g(-1) are obtained at the current densities of 0.2, 0.5, 1, 2, 5, 10, and 20 A g(-1), respectively. Even measured at 25 A g(-1), it still retains a desired discharge capacity of 364 mA h g(-1). Besides, the long-term cyclic stability up to 2000 cycles can be obtained at 5 A g(-1) and 20 A g(-1). (C) 2016 Elsevier Ltd. All rights reserved.