Metal Oxynitrides as Promising Electrode Materials for Supercapacitor Applications

Abstract

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 À 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.[a] U.

Nitridation Temperature Effect on Carbon Vanadium Oxynitrides for a Symmetric Supercapacitor

“…Thus, it is necessary to synthesize new electrode materials applicable in Faradaic capacitors. Recently, several achievements geared at improving the stability, conductivity and wettability of Faradaic materials have been reported such as the adoption of metal sulphides (MSs) [12], metal nitrides (MNs) [13] and metal oxynitride (MONs) [14]. For MNs, the oxygen (O 2− ) atoms in the metal octahedral position were completely replaced by nitrogen (N 3− ) atoms, while for the MONs (e.g., M = Ti [15], W [16], Mo [17], V [18]), the replacement is partial which leads to the presence of some metal oxides [14].…”

“…Among the greatest recent achievements, vanadium oxynitride materials has been considered to be an excellent candidate due to their superior outstanding electrochemical properties due to multiple oxidation states (V 5+ , V 4+ , V 3+ , V 2+ ) leading to an excellent specific capacity, and the presence of some vanadium oxides. VO x N y still suffers from poor rate performance, low specific surface area and aging effects [14,19]. However, most reports on vanadium oxynitride materials entail the use of vanadium oxide precursors such as VO 2 or V 2 O 5 resulting in the generation of aggregated VO x N y particles owing to the low melting point of the vanadium oxides [20].…”

Perspective on Micro-Supercapacitors

“…SCs are defined as an electrochemical capacitor device have received greatest attention nowadays. According to previous literatures, the SCs have important features such as long life span (>10 5 cycles) ( Lu et al, 2017 ; Kumar et al, 2019 ; Zhai et al, 2020b ) and higher energy density than electrochemical energy storage devices, and higher power density (5–15 kW kg −1 ) ( Guo et al, 2017 ) as compared to battery and fuel cell. On the basis of charge storage mechanism, the SCs are be divided into two types including the pseudocapacitors and electric double layer capacitors (EDLCs) ( Arbizzani et al, 1996 ; Hwang and Hyun, 2007 ; Miller et al, 2018 ; Seol et al, 2020 ).…”

Vanadium Monoxide-Based Free-Standing Nanofiber Hosts for High-Loading Lithium-Sulfur Batteries

“…Recently, metal suboxides/reduced oxides were investigated due to their high conductivity compared to their stoichiometric counterparts. Such host materials demonstrate strong LiPs binding via Lewis acid–base interactions and possibly catalytic properties. − These properties largely originate from oxygen vacancies in these materials, resulting in unsaturated metallic centers in the crystal lattice. , Few reports also investigate metal nitrides due to their excellent electrical conductivity and catalytic conversion sites. , The first report presenting the concept of reduced metal oxides for Li-S batteries was published recently in 2014 by Cui and co-workers, wherein they developed the Magnéli phase of Ti 4 O 7 . They integrated in-operando X-ray absorption near-edge structure studies with DFT calculations to demonstrate a strong chemical affinity of Ti 4 O 7 for LiPs and their ability to enhance the kinetics of LiPs to Li 2 S conversion .…”