Heterostructured Titanium Oxynitride-Manganese Cobalt Oxide Nanorods as High-Performance Electrode Materials for Supercapacitor Devices

• Published in: ACS applied materials & interfaces Vol. 12; no. 49; pp. 54524 - 54536
• Main Authors: Samdani, Jitendra Shashikant, Kang, Tong-Hyun, Lee, Byong-June, Jang, Yun Hee, Yu, Jong-Sung, Shanmugam, Sangaraju
• Format: Journal Article
• Language: English
• Published: American Chemical Society 09.12.2020
• Subjects: ammonia; carbonates; cobalt oxide; diodes; electric potential difference; electrochemical capacitors; electrodes; electrolytes; Energy, Environmental, and Catalysis Applications; nanorods; nanotubes; propylene; prototypes; synergism; titanium; TiON-MnCo2O4; coin cell supercapacitor; titanium oxynitride; symmetric supercapacitor; organic electrolyte; heterostructure
• ISSN: 1944-8244; 1944-8252; 1944-8252
• DOI: 10.1021/acsami.0c13803

Metal oxynitrides have been considered recently as emerging electrode materials for supercapacitors. Herein, we converted titanate nanotubes into a series of titanium oxynitride (TiON) nanorods at nitridation temperatures of 800, 900, and 1000 °C in ammonia gas and tested them as supercapacitor electrodes. TiON-800, TiON-900, and TiON-1000 showed capacities of 60, 140, and 71 F g–1, respectively, at a current density of 1 A g–1. However, because of TiON’s low capacity, a heterostructure (TiON-900/MnCo2O4) was designed based on the optimized TiON with MnCo2O4 (MCO). The heterostructure TiON-900-MCO and MCO electrode materials showed specific capacities of 515 and 381 F g–1, respectively, at a current density of 1 A g–1. The cycling stability retention of TiON-900 and MCO were 75 and 68%, respectively; moreover, the heterostructure of TiON-900-MCO reached 78% at a current density of 5 A g–1 over 5000 cycles. The increased capacity and sustained cycling stability retention are attributable to the synergistic effect of TiON-900 and MCO. A coin cell (CC)-type symmetric supercapacitor prototype of TiON-900-MCO was fabricated and tested in the voltage range of 0.0–2.0 V in 1 M LiClO4 in propylene carbonate/dimethyl carbonate electrolyte, and a 79% cycling retention capacity of TiON-900-MCO-CC was achieved over 10 000 cycles at a current density of 250 mA g–1. We demonstrated a prototypical single cell of TiON-900-MCO-CC as a sustained energy output by powering a red-light emitting diode that indicated TiON-900-MCo electrode materials’ potential application in commercial supercapacitor devices.