Volume 34, Issue 5-6

Nanoporous copper (NPC), a representative type of nanostructured materials, holds an extensive ability to generate propitious potential for a broad range of highly promising applications. Especially, with the advancement in fabrication techniques, NPC with numerous special and superior properties, such as unique pore structure, large surface-to-volume ratio, enlarged specific surface area, and high electrical and thermal conductivities, has boosted the interest to explore its electrochemical properties and extended its promising applications in energy, sensing, actuation, and catalytic systems. Therefore, timely updates of such a type of material are highly demanding and appealing for a broad audience. This review summarizes the latest advances in the development of NPC with a special focus on synthesis methods and state-of-the-art electrochemical applications such as electrocatalysts, sensors, and energy conversion/storage systems. The important scientific disputes and future research directions are also presented.

Cathodic protection is an important method to prevent the corrosion of the tank bottom plate. In this article, the research status in recent decades of the current density and potential distribution of the tank bottom plate in cathodic protection is summarized. The research status and problems of the analytical and numerical methods for tank bottom plate are described and discussed. A detailed summary of boundary condition modeling is carried out. It is proposed that the analytical method will be gradually replaced by numerical methods and the mathematical model and boundary conditions need to be further studied and improved. In addition, the combined use of a variety of numerical methods and a numerical simulation study on the vapor phase corrosion related to tank bottom will be a trend in the development of numerical simulation in the future.

The corrosion inhibition behavior of an imidazoline derivative, namely, 2-undecyl- N -carboxymethyl- N -hydroxyethyl imidazoline (UHCI) for carbon steel in 4 wt.% citric acid solutions was characterized by weight loss method and electrochemical techniques in conjunction with X-ray photoelectron spectrometer (XPS) technique. The inhibitor has a good anti-corrosion effect on the carbon steel in 4 wt.% citric acid solutions. The inhibition efficiency increases with UHCI concentrations from 0 up to 0.4 wt.%, yet declines a bit at 0.6 wt.% per contra with further augmentation of concentration. The inhibition efficiency declines with the rise of temperature from 20°C to 95°C, while it rises with the extension of soaking time from 2 h to 24 h. Two N 1s peaks that appeared in XPS spectra give proof of UHCI inhibitor adsorbed on the carbon steel surface.

This paper presents a high corrosion resistance Ni-graphene composite coating fabricated by co-electrodeposition on Cu substrate. First, GO was synthesized by improved Hummers’ method, and then different concentrations of GO aqueous solution were introduced to Ni Watt’s bath. During electrodeposition, GO and Ni ions were reduced simultaneously to form composite coating. The phase structure and morphology were covered by X-ray diffraction and scanning electron microscopy analysis, respectively. Atomic force microscopy (AFM) was employed to identify the surface topography of the coatings. Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), and electrochemical impedance spectroscopy (EIS) were used to study the synthesis of GO and its reduction during the plating process. Corrosion resistance of nanocomposite and that of pure Ni coating were compared by applying potentiodynamic polarization spectroscopy (PDS). The results showed that by increasing the amount of graphene oxide in solution, there has been a significant reduction in corrosion current density. As the EIS result showed, the high amount of GO reduction was obtained in GO concentration of 0.6 mg ml −1 and current density of 8 A dm −2 . It is in a good agreement with data obtained from PDS. Analyses showed that the corrosion current density of corresponding coating was improved up to 0.2 μA cm −2 , which means an improvement of about 100 times compared to pure Ni coating.