Advanced Pseudocapacitive Performances of a TiCT-ZnOHF/ZnO Nanocomposite for Energy Storage Applications.

The growing demand for efficient and high-performance energy storage systems is driving the exploration of novel materials and composites. Traditional electrode materials often face limitations in terms of energy and power densities. This article demonstrates a novel spray-coated cathode electrode system composed of TiCT MXene and zinc hydroxy fluoride/zinc oxide nanostars for energy storage applications in a neutral pH electrolyte (1M NaSO), thus avoiding corrosion problems related to water splitting reactions. Optimized TiCT-nanostar electrodes exhibit superior specific capacitance, achieving 236 F g at 5 mV s in cyclic voltammetry and 139 F g at 5 mV s in galvanostatic charge-discharge measurements, which is superior to pure TiCT (115 F g at 0.5 A g) and pure nanostar (108 F g at 0.5 F g) electrodes, used as reference. Additionally, an asymmetric TiCT||TiCT-nanostars supercapacitor device achieves a specific capacitance of 147 F g at 0.5 A g, an energy density E ≈ 46 W h kg at a power density P ≈ 875 W kg, and the highest P ≈ 16 650 W kg at E ≈ 14 W h kg. These findings demonstrate that zinc oxide nanostars combined with delaminated TiCT MXene hold a significant promise for efficient energy storage applications, leveraging the synergy between double-layer capacitance and pseudocapacitive effects.