Transition metal nitride thin films used as the electrodes for lithium-ion batteries and supercapacitors

The transition metal nitride (TMN) thin films used as the electrodes for lithium-ion batteries (LIBs) and supercapacitors (SCs) have been completely reviewed and systematically discussed in this article. After the introduction of current research status, the energy storage mechanisms in TMN materials are first classified and interpreted. Next, the principles and characteristics of thin film fabrication techniques used to deposit the TMN thin film electrodes are briefly introduced. Then the research results of LIBs and SCs using the TMN thin film electrodes are individually reviewed and discussed in detail. The design considerations for the TMN thin film electrodes applied to LIBs and SCs are summarized according to the case studies. Eventually, it is concluded that the sputtering deposition would be the mainstream technique for the fabrication of thin film electrodes as well as the modification and/or combination of fabrication process may be utilized to improve the electrochemical performance of thin film electrodes. The potential candidates of TMN thin film electrodes for the future development of LIBs and SCs have been announced. The exploitation of solid-state electrochemical energy storage (EES) devices would be the future trend owing to the safety considerations.