Metal Oxynitrides as Promising Electrode Materials for Supercapacitor Applications

In the past decade, due to the demands of the electrochemical energy storage sector, there has been a quest for novel supercapacitor materials that offer champion storage characteristics. Metal oxynitrides are seen as potential candidates for electrochemical energy storage owing to their high cyclability (up to 10(5) cycles), good intrinsic conductivity (30000-35000 S cm(-1)), good wettability, corrosion resistance, and chemical inertness. In this review, the use of metal oxynitrides as electrode materials for supercapacitors is discussed. A comparison of oxynitrides with other electrode materials, such as metal oxides, carbon-based materials, and their composites, is made. This study also places emphasis on the impact of synthesis techniques on the final properties of the material. In view of this critical analysis, we envisage future directions for this category of energy storage materials.