Quasi-one-dimensional van der Waals TiS₃ nanosheets for energy storage applications: Theoretical predications and experimental validation

To cease the ever-increasing energy demand, additional enthusiastic focus has been given to generate more sustainable energy from alternative renewable sources. Storage of these energies for future usage solely banks on energy storage devices. A diversity of electrode materials based on two-dimensional (2D) transition metals and their derivatives have enticed the whole world owing to their tunable properties. Transition metal trichalcogenides (MX₃ type) are the emergent class of 2D materials, which gathered a lot of interest because of their quasi-one-dimensional anisotropic properties with the van der Waals force of attraction in between the layers. Herein, TiS₃ being a MX₃-type of material is preferred as the battery type-supercapacitor electrode for energy storage applications with detailed theoretical predications and experimental validations. The highest capacitance attained for TiS₃ is found to be 235 F/g (105 C/g) at 5 mV/s with a battery type of charge storage mechanism. The asymmetric hybrid device is fabricated using Ti₃C₂T_x MXene nanosheets as a negative electrode, and a brilliant 91% of capacitance retention is accomplished with an extensive potential window of 1.5 V. The investigational discoveries are substantiated by theoretical simulation in terms of the quantum capacitance assessment and charge storage mechanisms.