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The inhibition effect of a Schiff base with several functional groups on the corrosion of aluminum in alkaline solution is studied by experimental techniques and density function theory (DFT) calculations. The Schiff base are characterized by 1 HNMR, 13 CNMR, FT-IR, and CHN elemental analysis. In addition, different electrochemical and corrosion techniques such as weight loss, tafel polarization, electrochemical impedance spectroscopy (EIS) and optical microscopy images are performed to analyze the inhibiting performances. In the Tafel measurements the cathodic Tafel slopes values incurred small changes with increasing the inhibitor concentration, which revealed that the inhibitor was adsorbed on the aluminum surface. The inhibition efficiencies are calculated from weight loss measurement and electrochemical tests. The adsorption of the inhibitor onto the aluminum surface follows the Langmuir adsorption isotherm with the free adsorption energy of −8.66 kJ mol −1 . The calculated adsorption energies and the amount of charge transfer obtained by DFT calculation revealed that corrosion inhibition effectively occurs with chemisorption, where new N Al bonds are formed between of N atoms in azo (–N N–) group and Al surface atoms, which is confirmed from ab initio molecular dynamics (AIMD) simulation. [ABSTRACT FROM AUTHOR]

We introduce high-performance polyaniline (PANI) nanocomposite supercapacitors based on gamma aluminum oxide (γ-Al 2 O 3 ) and gamma iron (III) oxide (γ-Fe 2 O 3 ) nanoparticles with a high specific surface area. PANI and its polymer nanocomposites are synthesized via in situ electropolymerization on gold electrodes. The structures and morphologies are characterized by cyclic voltammetry, FT-IR spectroscopy, SEM, TEM, and EDX. The electrochemical properties and specific surface area of the electrodes are investigated by galvanostatic charge–discharge, electrochemical impedance spectroscopy (EIS) and BET theory. The enhanced specific capacitance with higher surface area and conductivities is observed in PANI/γ-Fe 2 O 3 (342 F/g), PANI/γ-Al 2 O 3 (292 F/g) and PANI (180 F/g) electrodes with a constant current density of 1A/g. The cyclic performance of the PANI electrodes following 8000 cycles of operations were at 87% (PANI), 91% (PANI/γ-Al 2 O 3 ), and 93% (PANI/γ-Fe 2 O 3 ) of their initial capacitance. In addition, higher specific capacitances, higher conductivity and cyclic self-stabilities observed for the PANI/nanocomposite electrodes can provide new opportunities in the field of energy storage and supercapacitor applications. [ABSTRACT FROM AUTHOR]