• S S KOLEKAR

Articles written in Bulletin of Materials Science

• A mesoporous nickel oxide nanosheet as an electrode material for supercapacitor application using the 1-(2$^{\prime}$,3$^{\prime}$-dihydroxypropyl)-3- methylimidazolium hydroxide ionic liquid electrolyte

NiO nanosheets were deposited on the surface of a stainless steel substrate by using a facile, environmentally friendly, reflux deposition approach for supercapacitor (SC) applications. X-ray diffraction patterns and field emissionscanning electron microscopy images revealed the formation of a face centred cubic crystal structure with a uniform, compact, smoothly ordered nanosheet like structure. This study focuses on the electrochemical supercapacitive propertiesof NiO nanosheets with respect to cyclic voltammetry, galvanostatic charge–discharge and electrochemical impedance spectroscopy techniques in a 1-(2$^{\prime}$ ,3$^{\prime}$-dihydroxypropyl)-3-methylimidazolium hydroxide [DHPMIM][OH] ionic liquid (IL) as an electrolyte. The electrochemical study revealed that NiO (0.3 M) showed a high-specific capacitance of 205.5 F g$^{−1}$ andan excellent cycling stability (80% specific capacitance retention after 5000 cycles) in the [DHPMIM][OH] IL electrolyte. Thus, the result showed that NiO nanosheets act as an active electrode material hold for SCs.

• Binder-free synthesis of high-quality nanocrystalline ZnCo$_2$O$_4$ thin film electrodes for supercapacitor application

Supercapacitors as energy storage devices have attracted great attention due to their high-specific capacitance, fast rechargeability, high-power density, performance, long cycle life and low-maintenance cost. These unique advantages enable their applications in portable electronic devices, gadgets, hybrid electric vehicles, etc. However, developing flexible, high performance, stable and economic storage devices is the need of time. With this motivation, binder-free ZnCo$_2$O$_4$ thin films are synthesized on flexible stainless steel mesh by a hydrothermal method. The structural, morphological andphysicochemical properties of ZnCo$_2$O$_4$ are investigated using X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy (FESEM) and energy dispersive spectroscopy. FESEM images reveal thin films with flower-shaped microspheres composed of bunched nanowires providing a large surface area (72 m$^2$ g$^{−1}$) whichis confirmed by Brunauer–Emmett–Teller analysis. The electrochemical performance of the ZnCo$_2$O$_4$ thin film electrode exhibited a specific capacitance of 127.8 F g$^{−1}$ at a current density of 1 mA cm$^{−2}$. It also shows good rate capability and excellent electrochemical cycling stability (80.66% specific capacitance retention after 3000 cycles).

• # Bulletin of Materials Science

Volume 43, 2020
All articles
Continuous Article Publishing mode

• # Editorial Note on Continuous Article Publication

Posted on July 25, 2019