No abstract

Aqueous rechargeable batteries with good electrochemical performances have been considered as compelling alternatives in miniaturized energy storage units due to their small-size, better safety, greener manufacturing condition, and easy-torecycle process. Herein, a binder-free manganese oxide (MnO x ), comprising of MnO 2 and Mn 3 O 4 constructed by engineering it with zinc doping used as a cathode material for eco-friendly aqueous Zn ion battery is developed. A green and simple electrochemical deposition synthesis of Zn-doped Mn 3 O 4 À MnO 2 nanocomposite with vertically-oriented 3D porous cereal-like nanosheet framework (ZnMM-NSs) is reproducibly performed directly onto the surface of AgCNT modified Ni foam in a mild aqueous ZnSO 4 + MnSO 4 electrolyte. To the best of our knowl-edge, this is the first report on Zn doping in Mn 3 O 4 À MnO 2 nanocomposite and the subsequent device assembly for aqueous zinc-ion batteries. Zinc doping induced electrical/ionic conductivity enhancement, along with more active sites provided by 3D porous cereal-like nanostructures and multiple Mn valences, this ZnMM-NSs cell can deliver a high capacity, good rate performance, and satisfying cycling stability. Also, the Zn-doped manganese oxides are obtained by a green method, which can reduce the entire cost, the usage of toxic solvents, the consumption of energy, and the disposable by-product, paving the way for developing cost-effective, easy-to-recycle, and environmentally friendly next-generation energy storage systems.