Novel [111] oriented γ-Mo2N thin films deposited by magnetron sputtering as an anode for aqueous micro-supercapacitors

- [111] oriented γ-Mo2N thin film was prepared by reactive dc magnetron sputtering.
- The formation of (111) texture gives excellent electrochemical property.
- The optimum deposition temperature is much lower than that of the chemical route.
- The Mo2N film is a promising candidate of anode materials for micro-supercapacitors.

The γ-Mo2N thin films were deposited using reactive dc magnetron sputtering, and tested as an electrode material in an aqueous solution of Li2SO4 with a working potential window of 0.05V∼-0.85 V versus SCE. The morphology, structure and electrochemical properties were systematically studied for the films of different deposition conditions. It was found that the electrochemical property of the γ-Mo2N film depends not only on the deposition temperature but also on the nitrogen concentration in Ar-N2 gas mixture. The sample deposited for 1 h at 400 °C with nitrogen concentration x = 0.35 shows a dense microstructure and strong (111) texture. It exhibits the best electrochemical property, with a high volumetric capacitance of 722 F cm−3 at 5 mV s−1, moderate rate capability with a relaxation time constant of 220 ms, and excellent cycling stability of 100% capacitance retention after 2000 cycles. The (111)-oriented γ-Mo2N film is suggested to be a promising candidate of anode materials for micro-electrochemical-capacitors.

[111] oriented γ-Mo2N thin film was prepared by reactive dc magnetron sputtering. It exhibits excellent electrochemical property due to the formation of (111) texture and is suggested to be a promising candidate of anode materials for micro-supercapacitors.284