Chemically Integrated Two-Dimensional Hybrid Zinc Manganate/Graphene Nanosheets with Enhanced Lithium Storage Capability

Abstract

Hybrid inorganic/graphene two-dimensional (2D) nanostructures can offer vastly open large surface areas for ion transport and storage and enhanced electron transport, representing a promising material platform for next-generation energy storage. Here we report chemically integrated hybrid ZnMn₂O₄/graphene nanosheets synthesized <i>via</i> a facile two-step method for greatly enhanced lithium storage capability. The hybrid 2D nanosheets are composed of ultrafine ZnMn₂O₄ nanocrystals with a mean diameter of ∼4 nm attached to and well dispersed on the surface of reduced graphene oxide sheets. The hybrid nanosheets based anode offers a high capacity of ∼800 mAh g^–1 at a current rate of 500 mA g^–1, excellent rate capability, and long-term cyclability with reversible capacity of ∼650 mAh g^–1 over 1500 cycles at a current density of 2000 mA g^–1. Moreover, when tested in a temperature range of ∼0–60 °C, the designed anode can maintain high discharge capacities from 570 to 820 mAh g^–1.