Energy demand has become a persistent concern and high‐performance energy storage systems have increasingly undergone development. Supercapacitors and batteries pose great impact on energy storage and garner a great deal of attention from technologies and researchers alike. The performance of energy saving devices is primarily determined by the electrode material in terms of high specific capacitance, excellent conductivity, remarkable natural abundance, and unique electrochemical qualities, also large surface area. Cobalt (Co)‐based materials are unique electrode materials widely used in energy storage devices. Nevertheless, a combination of Co and ferrite materials such as nickel, zinc, and copper, or Co/nonferrite materials like metal–organic frameworks and layered double hydroxides has improved their ultimate efficiency. This review deals with energy storage applications of Co‐based materials, categorizing ferrites, their electrochemical characterization, performance, also design and manufacturing intended to supercapacitors and batteries applications. Summarizing the main outcomes of the literature on batteries and supercapacitors, energy storage systems comprising Co‐based materials combined with carbon nanotubes, graphene, silica, copper, zinc, nickel, cadmium, ferrous, and lanthanum are reviewed and discussed. Lithium‐ion batteries are investigated specifically, and perspectives on Co‐based ferrite development for future generations of supercapacitors and batteries are outlined.

Polypyrrole and polypyrrole/copper zinc iron oxide (copper zinc ferrite) nanocomposites were synthesized by in-situ polymerization using Ammonium Persulphate as oxidising agent. The nanocomposites were synthesized by mixing polypyrrole and copper zinc iron oxide in different weight percentages. The formation of nanocomposites and changes in the structural properties were investigated by characterizing the samples using XRD, FTIR, SEM and EDX analysis. The size of the particle was analysed by XRD using Scherrer equation and found to be in 20 nm range. DC conductivity was measured in the temperature range 300 K–473 K. The DC conductivity was found to be constant for the temperature range from 300 K–433 K. But the conductivity showed an exponential increase for the temperature 433 K–473 K, and it obeys Arrhenius relation. Activation energies were evaluated from Arrhenius plots for all compositions. Results show that incorporation of additive material significantly reduces the activation energy for the DC conductivity of the composites, and the decrease in the activation energy is also dependent on the amount of the nanoparticles in the composites. As the polymers are used in the various manufacturing products, this study indicates the possibility of using such polymers in the form of composites as superior insulating material in the fields of electrical or electronic insulation and allied areas

ZrO2 nanopowders were synthesized by low temperature solution combustion method using two different fuels namely glycine and oxalyldihydrazide (ODH). The phase confirmation was done by powder X-ray diffraction (PXRD) and Raman spectral analysis. Use of glycine resulted in ZrO2 with mixture of tetragonal and monoclinic phase with average crystallite size of ∼30nm. However, ODH as fuel aids in the formation of ZrO2 with mixture of tetragonal and cubic phase with average crystallite size ∼20nm. Further, in present work we present novel way to tune conductivity property of the nano ZrO2. We show that merely changing the fuel from glycine to ODH, we obtain better DC conductivity and dielectric constant. On the other hand use of glycine leads to the formation of ZrO2 with better AC conductivity and humidity sensing behavior. The dielectric constants calculated for samples prepared with glycine and ODH were found to be 45 and 26 respectively at 10MHz. The AC and DC conductivity values of the samples prepared with glycine was found to be 9.5×10−4Scm−1, 1.1×10−3Scm−1 and that of ODH was 7.6×10−4Scm−1, 3.6×10−3Scm−1 respectively