Enhancing Electrochemical Energy Storage with 3D Ti ₃ C ₂ T _x Hybrid Electrode Materials

Abstract MXenes have demonstrated significant promise in electrochemical energy storage due to their high electrical conductivity, excellent flexibility, and hydrophilicity. However, their susceptibility to stacking and oxidation limits the development of MXenes in energy storage. In this paper, 3D structured Ti ₃ C ₂ T _x (THM) is prepared. Subsequently, THM is used as the inner support structure, and polydopamine (PDA) is used as the outer shell structure to encapsulate the THM, and the uniformly dispersed and N‐doped spherical structure (THM@CN) is obtained after carbonization at 650 °C. Finally, NiS is uniformly cultivated on the surface of THM@CN by hydrothermal synthesis to acquire the electrode material NiS/THM@CN. The NiS/THM@CN electrode material has a weight capacitance of 2750 F g ⁻¹ (305.56 mAh g ⁻¹ /1 A g ⁻¹ ). Furthermore, the solid‐phase asymmetric HSC has an energy density up to 73.36 Wh kg ⁻¹ and, with the capacitance of the HSC system, is sustained at 88.5% of the initial value after 15 000 cycles. The proposed structure with THM as the inner support junction and CN as the outer shell has a high specific surface area and dispersion, as well as excellent electrochemical stability, which further promotes the application of Ti ₃ C ₂ T _x in high‐performance energy storage devices.