Magnetron sputtered NbN thin film electrodes for supercapacitors

Selecting suitable electrode materials is the key to develop high-performance supercapacitors. Herein, we report the niobium nitride (NbN) thin films prepared by reactive magnetron sputtering and investigate their electrochemical performances when used as supercapacitor electrodes. NbN thin film electrodes can achieve the optimal electrochemical performance with a volumetric capacitance of 707.1 F cm−3 and an outstanding cycling stability (remaining 92.2% after 20,000 cycles). Such impressive properties render the NbN thin films qualified as the promising candidates for supercapacitors or other energy storage systems.