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CNT based material are of vital importance in modern technology for their superior physical and chemical properties. In recent times, material developments for energy applications are focused for improvement of battery, capacitors, and electrodes for enhanced efficiency. High performance Supercapacitors with high energy densities are at the leading edge for renewable energy engineering device sector. CNT based Ni-Co-O material is of keen interest due to its possible applications as supercapacitors, electrocatalyst for metal/air battery and others. The hybrid material synthesis, morphology features and electrochemical features are vital to evaluate the material performances for energy applications. Electrical studies are also vital to evaluate the properties for device applications. In the present article, some stresses have been laid forward for the development of CNT-Ni-Co-O based hybrid material for supercapacitor high energy density applications.

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The present article reports a simple and cost-effective process to prepare the crystalline MgAl2O4 spinel using non-stoichometric amount of magnesium nitrate, aluminium nitrate by solution combustion route. Thiourea was used as a fuel and reducing agent while soaking was carried at 1000ºC with different soaking periods. After slow drying of mixed solutions at 80ºC for 4-5 hours a gel was formed and got characterized by DTA/TGA (Differential Thermal Analysis and Thermal Gravimetric Analysis) to observe the effect of temperature variation and identify the range of temperature where crystalline nature of the powder was noted. Powder sample was prepared from the gel after annealing at 1000ºC followed by soaking for 4 hours, 5 hours, 6 hours to compare the variation of particle size with respect to time. The calcined powders were characterized by XRD (X-ray powder diffraction) to determine the phases and crystal planes present in the sample, FT-IR (Fourier-transform infrared spectroscopy) to study the types of metal oxide or metal-metal bond present in the sample along with M-O coordination studies, FESEM (Field emission scanning electron microscopy) to observe the morphological structure of the sample, EDAX (Energy Dispersive X-Ray Analysis) to observe the percentage of each element present in the sample. Bulk densities were estimated from 2.4156 g/cm3 to 2.8571 g/cm3 and the rapid increase in apparent porosity of samples 7.4289%, 10.3630% and 32.51% for 4 hours 5 hours and 6 hours respectively were also noted. It had been observed that the average crystal size of spinel particles was about 48 nm, 36 nm, and 47 nm respectively. Finally, hardness of spinel was evaluated by Vicker Hardness test and evaluated to be10.52GPa (1073 HV), 4.087GPa (416.7HV) and 5.079 GPa (517.9HV).