Recent advances in two-dimensional inorganic nanosheet-based supercapacitor electrodes

Exfoliated two-dimensional (2D) nanosheets of inorganic solids exhibit various unique characteristics such as unusually high morphological and structural anisotropy, great diversity in composition and structure, and tunable physicochemical properties. The large 2D surface area and high electrochemical activity of inorganic nanosheets render them as potential materials for supercapacitor electrodes. The electrode performance of these nanosheets can be further improved by their hybridization with highly conductive and/or electrochemically active species. This review focuses on the application of 2D inorganic nanosheets as supercapacitor electrodes and versatile building blocks for synthesizing novel hybrid electrode materials. The crucial roles of 2D inorganic nanosheets in high-performance electrode materials for supercapacitors are discussed and several intriguing examples of 2D inorganic nanosheet-based electrode materials have also been provided. The perspective for future research in this field is discussed along with various strategies to optimize the electrode performance of 2D inorganic nanosheet-based hybrid materials.