Cordia Dichotoma as Corrosion Inhibitor for Aluminum

Abstract

Aluminum alloy corrosion behavior (AA6063) in a 0.5 M hydrochloric acid (HCl) solution was studied. It has been observed that the ethanolic extract of Cordia dichotoma seeds (EECdS) acts as an excellent inhibitor for AA6063 corrosion in a 0.5 M HCl solution. In this study, conventional weight loss, Fourier transformed infra-red spectroscopy (FTIR), electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) analysis techniques were used. It was found that the percentage inhibition efficiency increased with higher CdS concentrations. The thermodynamic and kinetic parameters, along with the equilibrium constant for the adsorption processes, showed that CdS performed well as an inhibitor. CdS adsorption on the alloy followed the Langmuir adsorption isotherm, at all the studied concentrations. FTIR, EIS and SEM investigations also indicated that CdS presence effectively lowered the dissolution currents.

Self‐Supporting Electrode of High Conductive PEDOT:PSS/CNTs Coaxial Nanocables Wrapped by MnO2 Nanosheets

“…The separation of peak spin-energy is 11.5 eV, which indicates the existence of Mn 4 + oxide phases. [24] Mnoxide phases also can be known from the O 1s core level spectra. The O 1s peak can be deconvoluted into three components related to Mn-OÀ Mn bond (530 eV) for tetravalent oxide, Mn-OÀ H bond (531.9 eV) for hydrated trivalent oxide and HÀ O-H bond (535.5 eV) for adsorbed water.…”

“…[32] The specific capacitance of MnO 2 /PEDOT:PSS/CNTs electrode is much higher than that of those similar electrodes in previously reported reports. [23][24][25][26]35] MnO 2 exhibits high theoretical specific capacitance, [36,37] especially the flower-like MnO 2 nanosheets have outstanding electrochemical performance. [38] Because of the uniform coating of PEDOT:PSS on CNTs, the highly conductive coaxial nanocable structure of PEDOT:PSS/ CNTs was formed.…”

“…[25] Sharma et al synthesized a MCNTs-PSS/PEDOT/MnO 2 nano-composite electrode with the specific capacitance of 375 Fg À 1 in 0.5 M Na 2 SO 4 (at scan rate of 5 mVs À 1 ). [24] These studies shows the extraordinary improvements of specific capacitance and electrical conductivity of the hybrid electrode materials after combining with conductive polymer PEDOT. PEDOT acting as a conductive bridge between CNTs and MnO 2 , could enormously enhance the transport efficiency of electrons.…”

“…[19,20] Many researchers attempted to modify CNTs by using Poly (3,4ethylenedioxythiophene) (PEDOT) owing to its excellent electrical conductivity and predominant specific energies. [19][20][21][22][23][24] Zhao et al reported a PEDOT:PSS/MWCNTs composite film with specific capacitance of 485 Fg À 1 at the current density of 1 Ag À 1 and capacitance retention ratio of 95% after 2000 cycles at current density of 2 Ag À 1 . [25] Sharma et al synthesized a MCNTs-PSS/PEDOT/MnO 2 nano-composite electrode with the specific capacitance of 375 Fg À 1 in 0.5 M Na 2 SO 4 (at scan rate of 5 mVs À 1 ).…”

“…After modification by DHIL and PEDOT:PSS solution, negative electrons were carried on the surface of CNTs. [24] Mn 2 + cations were electrostatic adsorbed and grew to MnO 2 nanosheets along the CNTs during electrodepositing process.…”