Recent progress in nanostructured transition metal nitrides for advanced electrochemical energy storage

On the heels of the rapid development of portable electronics, electric vehicles, and renewable energy, electrochemical energy storage (EES) devices have become more prevalent. Electrode materials are key components for EES devices and largely determine their energy storage performance. Transition metal nitrides (TMNs) are promising electrode materials suitable for a wide range of EES devices including supercapacitors and rechargeable batteries due to their unique electronic structure, high conductivity, and large volumetric energy density, as well as good electrocatalytic activity. However, the practical implementation of TMNs in EES systems is hampered by their limited electrochemically active sites, unsatisfactory capacitance (capacity), and poor durability and flexibility. In comparison, TMN-based nanocomposites have been demonstrated to possess improved EES properties because they boast potential synergistic effects that ameliorate the electron and ion conductivity, prevent agglomeration, enhance the active sites, and improve the electrochemical stability. In this paper, recent advances pertaining to TMN-based hybrid materials are reviewed from the perspective of advanced EES systems with the focus on advanced supercapacitors and lithium-sulfur batteries. The challenge and future opportunities confronting TMN-based electrode materials in high-performance EES systems are also discussed.