Facile self-assembly of sandwich-like MXene V2CTx/Ag/rGO/MWCNTs layered multiscale structure nanocomposite

MXene is widely used in the supercapacitors, fuel cells and other fields due to its excellent conductivity and hydrophilicity. V has multiple oxidation states that allow V2CTx to participate in more redox reactions, and has good energy storage potential. Ag particles, rGO and MWCNTs are used to modify V2CTx to fully exploit the electrochemical properties of V2CTx. The doping of Ag particles, rGO and MWCNTs can well prevent the collapse and accumulation of V2CTx. A number of Ag particles, rGO and MWCNTs enter into the layers of V2CTx, which can increase the layer spacing. The expansion of interlayer spacing can expose more active contact sites and shorten the diffusion path of electrolyte ions. Ag particles, rGO and MWCNTs transform the original two-dimensional structure into a three-dimensional structure, which can provide a fast transport channel for charge transport and ion diffusion. Moreover, the close contact of Ag particles, rGO and MWCNTs enables the cross-boundary transport of carriers more rapid and convenient. The capacitance contribution rate of V2CTx + Ag + rGO + MWCNTs composite that is modified with Ag particles, rGO and MWCNTs reaches 86.6%. The results show that the electrochemical performance of V2CTx + Ag + rGO + MWCNTs composites has a more promising future.