ALD titanium nitride coated carbon nanotube electrodes for electrochemical supercapacitors

We present titanium nitride (TiN) coated carbon nanotube (CNT) forest electrodes by means of atomic layer deposition (ALD) to store charges in the electrochemical supercapacitors for the first time. The specific achievements as compared with the state-of-art supercapacitor electrodes include: (1) 400 times higher capacitance than a flat-shape electrode; (2) conformal and uniform coating of TiN; and (3) greater than 500% enhancement of electrochemical capacitance at 81mF/cm² than CNT electrodes without TiN at 14mF/cm² due to increased oxygen vacancies on the TiN surfaces. As such, this work presents a new path to increase energy density of supercapacitors using TiN-based porous materials.