Langmuir–Blodgett assembly of sulphonated graphene nanosheets into single- and multi-layered thin films

Sulphonated graphene nanosheets were successfully assembled into ordered single-layered film by Langmuir–Blodgett deposition with assistance of ethanol. Packing density of such-prepared film can be tailored by adjusting the surface pressure with the topographical feature transferring from loosely scattered, closely packed to densely packed ones. Multilayered films can also be formed by direct layer-by-layer accumulation with no need of binding materials. Such kind of thin film exhibits ultrahigh capacitance and excellent cyclic stability which is superior to that of its powder counterpart, demonstrating high potential as thin-film electrode in supercapacitor, solar cell, capacitive deionization of saline water and so on.