This work reports the facile, controlled, and low-cost synthesis of a nickel oxide and polyaniline (PANI) nanocomposites-based electrode material for supercapacitor application. PANI-NiO nanocomposites with varying concentrations of NiO were synthesized via in-situ chemical oxidative polymerization of aniline. The XRD and FTIR support the interaction of PANI with NiO and the successful formation of the PANI-NiO-x nanocomposite. The SEM analysis showed that the NiO and PANI were mixed homogenously, in which the NiO nanomaterial was incorporated in porous PANI globular nanostructures. The multiple phases of the nanocomposite electrode material enhance the overall performance of the energy-storage behavior of the supercapacitor that was tested in 1 M H₂SO₄ using cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS). Among the different nanocomposites, PANI-NiO-3 exhibit the specific capacitance of a 623 F g⁻¹ at 1 A g⁻¹ current density. Furthermore, the PANI-NiO-3 electrode retained 89.4% of its initial capacitance after 5000 cycles of GCD at a 20 A g⁻¹ current density, indicating its significant cyclic stability. Such results suggest that PANI-NiO nanocomposite could be proposed as an appropriate electrode material for supercapacitor applications.

Zinc–air batteries (ZABs) have garnered significant interest as a viable substitute for lithium-ion batteries (LIBs), primarily due to their impressive energy density and low cost. However, the efficacy of zinc–air batteries is heavily dependent on electrocatalysts, which play a vital role in enhancing reaction efficiency and stability. This scholarly review article highlights the crucial significance of electrocatalysts in zinc–air batteries and explores the rationale behind employing Fe-Co-Ni-Zn-based metal–organic framework (MOF)-derived hybrid materials as potential electrocatalysts. These MOF-derived electrocatalysts offer advantages such as abundancy, high catalytic activity, tunability, and structural stability. Various synthesis methods and characterization techniques are employed to optimize the properties of MOF-derived electrocatalysts. Such electrocatalysts exhibit excellent catalytic activity, stability, and selectivity, making them suitable for applications in ZABs. Furthermore, they demonstrate notable capabilities in the realm of ZABs, encompassing elevated energy density, efficacy, and prolonged longevity. It is imperative to continue extensively researching and developing this area to propel the advancement of ZAB technology forward and pave the way for its practical implementation across diverse fields.

The effectiveness of sodium dodecyl sulfate (SDS) is investigated as an inhibitor against a 0.5 M H ₂ SO ₄ solution on mild steel (MS). The method was conducted for the calculation of critical micelle concentration (CMC) calculation, weight loss and potentiodynamic polarization. The SDS-coated steel samples were characterized by field emission scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray energy dispersive spectroscopy and atomic force microscopy to understand the surface morphologies after exposure to the CMC of SDS solution. Conductivity measurements were performed to determine the CMC of the SDS solution. It appears that SDS is a perfect inhibitor of MS corrosion, as the weight loss measurement result found an inhibition efficiency of SDS of approximately 98.37% in 0.5 M H ₂ SO ₄ solution. We also found, from the Tafel plot, a corrosion current of 0.98 × 10 ⁻³ A cm ⁻² at CMC (0.0077 M), when MS was dipped for 9 h in 0.5 M H ₂ SO ₄ . SDS enhances the corrosion resistance of MS in acidic environments and its potential implications for industrial applications. It varies with SDS concentrations, which is attributed to the development of a protective Fe ²⁺ –SDS complex on the MS surface.