Gelation of Two-dimensional Materials for Energy Storage Applications

Due to the unique layered structure, exceptional electrical, and chemical properties of two-dimensional (2D) materials, large efforts have been investigated for their energy storage applications. However, as the consequence of the erratic aggregation and layer-by-layer restacking of 2D sheets, severe accessible surface loss preserves their outstanding properties in the practical applications. Gelation in solution is an advantageous way to achieve the self-assembly of nanomaterials with different structures. The prepared hydrogels exhibit interconnected pores and thus present a better utilization of the terminal active sites on 2D sheets and a higher permeability for mass transportation. Moreover, gelation also shows a superior value on the pore design which is conducive to the mass storage and void space tailor. In this paper, we discussed the gelation mechanism of graphene and its analogues starting from colloidal suspensions , summarized different ways of gelation methods, and listed the strategies for their structural control. In addition, research of 2D materials hydrogels featuring high electrochemical performance, multiple functions for energy storage devices are also viewed.