A study of the inhibiton of copper corrosion by triethyl phosphate and triphenyl phosphate self-assembled monolayers

Nano- to Micro-Self-Aggregates of New Bisimidazole-Based Copoly(ionic liquid)s for Protecting Copper in Aqueous Sulfuric Acid Solution

This study presents the synthesis of two new bisimidazole-based copoly(ionic liquid)s (PILs) through multistep preparation routes. It is shown that the target PILs can display orderly molecular stacking, and nano- to micro-self-aggregates are yielded in aqueous sulfuric acid solution, which are characterized by various technologies including scanning electron microscopy, transmission electron microscopy, and dynamic light scattering. The studied PIL aggregates show strong chemical adsorption onto the copper surfaces demonstrated by Fourier transform infrared spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. Furthermore, the anticorrosion performance of the studied PIL aggregates is shown using polarization curves and impedance spectroscopy. As a result, the target PIL aggregates show great corrosion inhibition performance to protect copper in aggressive acid medium.

Insights into the corrosion inhibition of copper in hydrochloric acid solution by self-assembled films of 4-octylphenol

4-Octylphenol was used to form self-assembled films on copper to inhibit its corrosion in 0.5 M HCl solution.

Fast formation of superhydrophobic octadecylphosphonic acid (ODPA) coating for self-cleaning and oil/water separation

A simple and fast method to prepare robust superhydrophobic octadecylphosphonic acid (ODPA) coating on oxidized copper mesh for self-cleaning and oil/water separation is reported here. The substrate of the copper mesh was first oxidized by simple immersion in an aqueous solution of 1.0 M NaOH and 0.05 M K2S2O8 at room temperature for 30 min, which was then covered with micro- and nanoscale Cu(OH)2 on the surface. Subsequently, the oxidized copper mesh was immersed in 2 × 10(-4) M octadecylphosphonic acid/tetrahydrofuran (ODPA/THF) solution, an ODPA coating formed on the oxidised copper mesh. The ODPA coating formation process takes place rapidly, almost in 1 second, which makes the as-prepared mesh exhibit superhydrophobicity with the water contact angle of approximately 158.9° and superoleophilicity with the oil contact angle of 0°. Moreover, the as-prepared mesh has self-cleaning effect and can be repeatedly used to efficiently separate a series of oil/water mixtures like gasoline/water and diesel/water. Interestingly, straightforward oxidation of a copper substrate produces a "water-removing" type oil/water separation mesh with underwater superoleophobicity, whereas ODPA coating on the oxidized copper mesh produces an "oil-removing" type oil/water separation mesh with superhydrophobicity and superoleophilicity. This interesting conversion results from a small amount of ODPA and takes place very rapidly.

Electrochemical and molecular simulation studies on the corrosion inhibition of L-glutamine monolayers on an iron surface

L-Glutamine was used to form monolayers for the inhibition of the corrosion of iron in 0.50 mol dm-3 H2SO4. The protection ability of the films was examined by electrochemical impedance spectroscopy. The mechanism of adsorption is discussed using quantum chemical calculations and molecular simulations. Scanning electron microscopy was applied to confirm the formation of L-glutamine monolayers and the inhibitive effect. The results indicate that the molecules of L-glutamine are able to form films on the surface of iron and longer immersion time of the iron electrode in the solution results in a stronger inhibition ability of the films. The films are formed spontaneously by the adsorption of L-glutamine with a specific affinity of its head-group to the iron surface, hence, the densely and ordered monolayers can be considered as self-assembled.