Tungsten nitride-coated graphene fibers for high-performance wearable supercapacitors

Abstract

Graphene-fiber (GF) supercapacitors attract significant research attention in the field of wearable devices. Unfortunately, there still remains a need for the active materials with increased energy density. Transition Metal Nitrides...

Achieving extraordinary enhanced reversible capacitance through the synergy between octahedral structure and isovalent ionic doping

“…46 The rest of the peaks appearing at higher binding energy belong to pyrrolic-N (399.9 eV) and graphitic-N (401.7 eV), indicating that the carbon cloth substrate is nitrided after the nitriding process. 47 All these results can support the formation of WN and the success of Co doping in the form of substitution, as well as the doping induced apparent crystal structure variation due to the easy degradation of highly symmetric octahedral WN (the Jahn–Teller effect).…”

“…4a and S3 †) have no anodic peaks, but cathodic peaks were present, which are the typical capacitive charge storage features instead of the battery-type redox reaction behavior. According to previous studies, in the acid electrolyte, the energy storage process of WN is dominated by the reversible adsorption/desorption of H + , which can be expressed as follows: 47,48 WN + aH + + ae À 4 H a WN It is believed that the area of CV curves reects the capacitance of the electrode. As shown in Fig.…”

Recent Developments of Transition Metal Compounds-Carbon Hybrid Electrodes for High Energy/Power Supercapacitors

“…The textile fibers wattled by CNT with high conductivity could largely promote the electrolyte ions/electrons transfer through the in-plane direction, and the MnO 2 -CNT-textile electrode exhibited a high energy density of 5–20 Wh kg −1 at the high power density of 13 kW kg −1 . In another article, Salman and co-workers successfully integrated tungsten nitride (WN) with reduced graphene oxide fibers (rGOF) to obtain a WN-rGOF hybrid by a simple hydrothermal method [ 54 ]. Owing to the high tensile strength, excellent flexibility and high electrical conductivity of rGOF, large capacitance and high chemical stability of WN electrode can be obtained.…”

Soft materials for wearable supercapacitors

“…Kim and co-workers [137] integrated Tungsten with rGO to fabricate hybrid fiber supercapacitors with high electrochemical performances (16.29 F cm -3 at 0.05 A cm -3 , an energy density of 1.448 mW h cm -3 and 84.7% capacitance retention after 10000 cycles). To further improve the stretchability of metal compound-based electrodes,…”