Unleashing the power of 3D Ti3C2Tx: A breakthrough in electrochemical energy storage

The tendency of Ti 3 C 2 T x nanosheets to be stacked makes it challenging to immobilize the active material, thus limiting the performance of the storage device. Integrating two-dimensional Ti 3 C 2 T x into three-dimensional (3D) structures is considered one of the important yet challenging approaches to realize ultra-high-performance supercapacitors. In this study, we report the preparation of Ti 3 C 2 T x into a 3D network interconnection structure using the sacrificial template method, with polydopamine (PDA) serving as a coating material for encapsulation. Subsequently, the Ti 3 C 2 T x /PDA composite is combined with NiS as an electrode material. The 3D Ti 3 C 2 T x structure effectively hinders the stacking of Ti 3 C 2 T x , while the –OH groups on the surface of PDA form non-covalent interactions with the functional groups of 3D Ti 3 C 2 T x , preventing its oxidation and accelerating electron transfer. The nitrogen atom in PDA can anchor Ni-S to avoid its detachment, which leads to better electrochemical properties of the prepared composites. Ni-S/3D Ti 3 C 2 T x @PDA as an electrode material had a high specific capacitance of 281.8 mAh/g (1 A/g). The asymmetric supercapacitor using Ni-S/3D Ti 3 C 2 T x @PDA as the anode material achieved a high energy density of 35.5 W kg −1 at 1600 W kg −1 power density, and excellent cycling stability, possessing 98.83 % cycle retention and 84.98 % capacity efficiency at 3 A/g for 10,000 cycles. In summary, it can be seen that Ni-S/3D Ti 3 C 2 T x @PDA materials have great potential for development in supercapacitors.