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Glucose-induced composite coatings containing crystalline calcium phosphate and Mg(OH)2 interlayer were prepared on pure Mg substrate through hydrothermal deposition from alkaline solution. Surface composition, morphology and corrosion resistance of the coatings were characterized through XRD, FTIR, SEM, XPS, electrochemical and hydrogen evolution measurements. Results reveal that calcium phosphate coatings were composed of dicalcium phosphate anhydrous, calcium-deficient hydroxyapatite and hydroxyapatite. Corrosion resistance of pure Mg specimens was improved by the formation of such a calcium phosphate coating. The findings provide a novel strategy to design calcium phosphate conversion coatings with satisfactory corrosion resistance for biodegradable Mg implants.

A (polyvinylpyrrolidone (PVP)/deoxyribonucleic acid (DNA))n coating was fabricated via layer-by-layer (LbL) assembly dip coating method. The surface morphologies, chemical compositions and corrosion resistances of the coatings were investigated using field-emission scanning electron microscopy, X-ray photoelectron spectrometer, Fourier transform infrared, X-ray diffractometer and electrochemical and hydrogen evolution measurements. The results indicated that the (PVP/DNA)n coating shows a smooth surface with shallow scratches and some corrosion cracks, which possesses a good corrosion resistance in simulated body fluid, especially for n = 20. The (PVP/DNA)n coating can be used as a inducer to construct a biomimetic biocompatible Ca-P coating on Mg alloys. Additionally, we suggest and discuss a corrosion mechanism for the coating.

Complications related to corrosion and infection of magnesium (Mg) implants are encountered by physical barrier and local drug delivery system. In this work, the multilayer films composed of ciprofloxacin (CIP) and SiO2 nanoparticles were fabricated on Mg alloys by the spin-spray layer-by-layer assembly method. The resultant films were characterized via FT-IR, XPS, SEM and EDS techniques. The corrosion behaviors of the multilayer films were investigated via electrochemical tests and hydrogen evolution experiment. The obtained films showed corrosion resistance, self-healing ability, antibacterial efficacy and a prolonged release profile. The results also suggested that the loading dosage and the release rate of CIP could be controlled by the assembly parameters. Moreover, the in vitro release kinetics of CIP from the multilayer films could be fitted with the pseudo-second-order model.

We reported the impact of oxygen plasma treatment on solution-processed amorphous indium gallium zinc oxide (a-IGZO) thin film transistors (TFTs). Plasma-treated devices showed higher mobility, larger on/off current ratio, but a monotonically increased SS with plasma treatment time as well. The phenomenon was mainly due to two components in oxygen plasma, atomic oxygen and O2+, according to the photoluminescence (PL) measurement. Atomic oxygen reacted with oxygen vacancies in channel layer resulting in an improved mobility, and O2+ tends to aggregated at the surface acting as trapping states simultaneously. Our study suggests that moderate oxygen plasma treatment can be adopted to improve the device performance, while O2+ should be eliminated to obtain good interfacial states.