2D Ti₃C₂T_x MXene nanosheets coated cellulose fibers based 3D nanostructures for efficient water desalination

We introduce a novel and facile synthesis strategy to design 2D MXene (Ti₃C₂T_x) nanosheets (NSs) coated cellulose fibers (CLF) based 3D nanostructures (CLF@Ti₃C₂T_x) to overcome the drawbacks of co-ion expulsion in carbon-based, commonly used CDI electrodes and restacking of MXene NSs due to van der Waals forces in the pure MXene based electrodes. CLF extracted from facial tissue paper were used as a porous carbon core-substrate to coat shell of exfoliated two-dimensional (2D) Ti₃C₂T_x NSs in order to prepare unique CLF@Ti₃C₂T_x nanostructures composite by an improved dip-coating method. After appropriate structural and chemical characterization, the designed CLF@Ti₃C₂T_x material was assembled in symmetric capacitive deionization (CDI) cell as an active electrode and the electrochemical properties and desalination capacity were studied in detail. Interestingly, the CLF@Ti₃C₂T_x based active electrodes displayed good specific capacitance of 142 F·g⁻¹ in 1 M sodium chloride electrolyte, and high salt adsorption capacitance of 35 mg·g⁻¹ compared with the pure MXene and carbon-based electrodes at an applied voltage of 1.2 V, with considerable cycling stability of 10 cycles. Inspired by the conventional chemical gilding process, the proposed unique and low-cost synthesis strategy and unique design open a new way to develop MXene-carbon based composite nanostructures for CDI and energy storage applications.