Vishnu Prataap - Academia.edu (original) (raw)

Papers by Vishnu Prataap

Surface Engineering, 2018

The present work addresses high-performance Ruthenium Oxide (RuO 2) electrodes prepared by using ... more The present work addresses high-performance Ruthenium Oxide (RuO 2) electrodes prepared by using a simple pulse electrodeposition method. For the comparison purpose, two different precursors, namely, ruthenium (III) nitrosyl sulphate (RuNS) and ruthenium trichloride (RuCl 3), were used in this study. The coatings were subjected to material characterisation such as Field Emission Scanning Electron Microscopy and Energy-Dispersive X-ray Spectroscopy, Xray diffraction and Transmission electron microscopy as well as electrochemical characterisation such as Cyclic Voltammetry, Electrochemical Impedance Spectroscopy and charge/discharge. The RuNS-RuO 2 coating exhibited excellent specific capacitance (1724 F/g at 5 A/g) with a remarkable rate capability. This value is significantly higher (52%) than the value obtained for RuCl 3-RuO 2 electrode material at 5 A/g. The findings provide valuable information on the potential use of RuNS as a precursor for synthesising RuO 2 and pulse electrodeposition process to produce electrodes for supercapacitors.

Chemical Communications, 2017

Herein, we present the electrochemical fabrication of a hydroxide surface-covered nickel–cobalt a... more Herein, we present the electrochemical fabrication of a hydroxide surface-covered nickel–cobalt alloy and its superior catalytic activity towards the electrochemical oxygen evolution reaction in alkaline media.

Applied Clay Science, 2016

The present investigation is on processing of a series of clay polystyrene nanocomposite (CPS) co... more The present investigation is on processing of a series of clay polystyrene nanocomposite (CPS) coatings containing different adduct modified montmorillonite (Mt) for corrosion resistance coating applications. The corrosion properties were studied using potentiodynamic and electrochemical impedance spectroscopy measurements in 3.5 wt% aqueous NaCl electrolyte. The CPS coatings offered enhanced corrosion protection for Aluminum 6061 alloy even at high clay loading (20 wt%). The order of their protection efficiency was CPS-AMt N Pristine PS N Pristine Na +-Mt. Dispersion of Mt in the polystyrene matrix resulted in significant improvement of properties such as corrosion protection, optical clarity, electrical conductivity and thermal stability.

Microchimica Acta, 2016

Direct current electro-deposition is a promising method to synthesis graphene oxide (GO) reinforc... more Direct current electro-deposition is a promising method to synthesis graphene oxide (GO) reinforced copper matrix composites with improved comprehensive property. The microstructure of deposited material largely determines the properties of composites. Here, the effect of current density and GO concentration in electrolyte on microstructure, thermal and mechanical properties of the fabricated composites by electro-deposition were systematically investigated. With optimization of current density and the GO concentration, GO was highly reduced and uniformly dispersed in copper matrix. Compared with pure copper foil, the thermal conductivity of the composite foil was up to 503.39 W m − 1 K − 1 , the maximum hardness reached 3.32 GPa and the ultimate tensile strength and elongation of the composite foil were increased by 22.8% and 2.8% respectively. The simultaneously enhancement in thermal and mechanical properties of the composites can be ascribed to the positive role of GO reinforcement in microstructure refinement and its partly reduction during electrodeposition.

Current Applied Physics, 2018

With developments in energy storage devices, supercapacitors are gaining more attraction because ... more With developments in energy storage devices, supercapacitors are gaining more attraction because of their potential to excel batteries shortly. In this work, ruthenium oxide (RuO 2) has been deposited on stainless steel and studied the influence of surface modification of solid electrodes on capacitance properties. Hydrous ruthenium oxide was plated by different modes such as potential sweep method (cyclic voltammetric), constant potential method (chronoamperometry) and optimised potential pulse method using a recently reported precursor material namely ruthenium nitrosylsulfate (RuNS). The structural information and morphology of electrodeposits were characterised by X-ray diffractometer and scanning electron microscope respectively. The XRD studies indicate a poor crystalline state for RuO 2 in all the modes of deposition but can contribute to a higher surface area when compared to a highly crystalline form. The SEM analysis revealed the formation of surface modification concerning the change of potential mode. Mud-cracked morphology, spherical particles and dendrimeric morphology observed on chronoamperometry, potential pulse and cyclic voltammetry respectively. Electrochemical studies were also conducted on the samples to assess their performance for supercapacitor applications. The spherical particles of hydrous RuO 2 show high performance of capacitance behaviour 1180 F/g in 0.5 M H 2 SO 4 at the scan rate of 5 mV/s. Dendrimeric morphology and mud-cracked morphology shows 573 F/g and 546 F/g respectively in same 0.5 M

Surface Engineering, 2018

The present work addresses high-performance Ruthenium Oxide (RuO 2) electrodes prepared by using ... more The present work addresses high-performance Ruthenium Oxide (RuO 2) electrodes prepared by using a simple pulse electrodeposition method. For the comparison purpose, two different precursors, namely, ruthenium (III) nitrosyl sulphate (RuNS) and ruthenium trichloride (RuCl 3), were used in this study. The coatings were subjected to material characterisation such as Field Emission Scanning Electron Microscopy and Energy-Dispersive X-ray Spectroscopy, Xray diffraction and Transmission electron microscopy as well as electrochemical characterisation such as Cyclic Voltammetry, Electrochemical Impedance Spectroscopy and charge/discharge. The RuNS-RuO 2 coating exhibited excellent specific capacitance (1724 F/g at 5 A/g) with a remarkable rate capability. This value is significantly higher (52%) than the value obtained for RuCl 3-RuO 2 electrode material at 5 A/g. The findings provide valuable information on the potential use of RuNS as a precursor for synthesising RuO 2 and pulse electrodeposition process to produce electrodes for supercapacitors.

Chemical Communications, 2017

Herein, we present the electrochemical fabrication of a hydroxide surface-covered nickel–cobalt a... more Herein, we present the electrochemical fabrication of a hydroxide surface-covered nickel–cobalt alloy and its superior catalytic activity towards the electrochemical oxygen evolution reaction in alkaline media.

Applied Clay Science, 2016

The present investigation is on processing of a series of clay polystyrene nanocomposite (CPS) co... more The present investigation is on processing of a series of clay polystyrene nanocomposite (CPS) coatings containing different adduct modified montmorillonite (Mt) for corrosion resistance coating applications. The corrosion properties were studied using potentiodynamic and electrochemical impedance spectroscopy measurements in 3.5 wt% aqueous NaCl electrolyte. The CPS coatings offered enhanced corrosion protection for Aluminum 6061 alloy even at high clay loading (20 wt%). The order of their protection efficiency was CPS-AMt N Pristine PS N Pristine Na +-Mt. Dispersion of Mt in the polystyrene matrix resulted in significant improvement of properties such as corrosion protection, optical clarity, electrical conductivity and thermal stability.

Microchimica Acta, 2016

Direct current electro-deposition is a promising method to synthesis graphene oxide (GO) reinforc... more Direct current electro-deposition is a promising method to synthesis graphene oxide (GO) reinforced copper matrix composites with improved comprehensive property. The microstructure of deposited material largely determines the properties of composites. Here, the effect of current density and GO concentration in electrolyte on microstructure, thermal and mechanical properties of the fabricated composites by electro-deposition were systematically investigated. With optimization of current density and the GO concentration, GO was highly reduced and uniformly dispersed in copper matrix. Compared with pure copper foil, the thermal conductivity of the composite foil was up to 503.39 W m − 1 K − 1 , the maximum hardness reached 3.32 GPa and the ultimate tensile strength and elongation of the composite foil were increased by 22.8% and 2.8% respectively. The simultaneously enhancement in thermal and mechanical properties of the composites can be ascribed to the positive role of GO reinforcement in microstructure refinement and its partly reduction during electrodeposition.

Current Applied Physics, 2018

With developments in energy storage devices, supercapacitors are gaining more attraction because ... more With developments in energy storage devices, supercapacitors are gaining more attraction because of their potential to excel batteries shortly. In this work, ruthenium oxide (RuO 2) has been deposited on stainless steel and studied the influence of surface modification of solid electrodes on capacitance properties. Hydrous ruthenium oxide was plated by different modes such as potential sweep method (cyclic voltammetric), constant potential method (chronoamperometry) and optimised potential pulse method using a recently reported precursor material namely ruthenium nitrosylsulfate (RuNS). The structural information and morphology of electrodeposits were characterised by X-ray diffractometer and scanning electron microscope respectively. The XRD studies indicate a poor crystalline state for RuO 2 in all the modes of deposition but can contribute to a higher surface area when compared to a highly crystalline form. The SEM analysis revealed the formation of surface modification concerning the change of potential mode. Mud-cracked morphology, spherical particles and dendrimeric morphology observed on chronoamperometry, potential pulse and cyclic voltammetry respectively. Electrochemical studies were also conducted on the samples to assess their performance for supercapacitor applications. The spherical particles of hydrous RuO 2 show high performance of capacitance behaviour 1180 F/g in 0.5 M H 2 SO 4 at the scan rate of 5 mV/s. Dendrimeric morphology and mud-cracked morphology shows 573 F/g and 546 F/g respectively in same 0.5 M