Corrosion Resistance of Three Arc-sprayed Zinc Coatings in 3.5% NaCl Solution
Pure Zn,Zn-Al alloy and Zn-Al pseudo-alloy coatings were prepared on Q235 steel surface by arc spraying technique.The corrosion resistance of these coatings was investigated by immersion testing and electrochemical measurements in 3.5% NaCl solution.The surface morphology of the samples after test and the phase composition of corrosion products were analyzed by using electron microscopy(SEM) and X-ray diffraction(XRD).The results show that the corrosion resistance of the coatings decreased sequentially in the order of Zn-Al pseudo alloy coating,Zn-Al alloy coating,and pure Zn coating.
The role of ZnS shell on the photo-physical properties within CuInS2/ZnS quantum dots (QDs) is carefully studied in optoelectronic devices. Linearly increasing voltage technique has been employed to investigate the charge carrier dynamics of both CuInS2 and CuInS2/ZnS QDs films. This study shows that charge carriers follow a similar behavior of monomolecular recombination in this film, with their charge transfer rate correlates to the increase of applied voltage. It turns out that the ZnS shell could affect the carrier diffusion process through depressing the trapping states and would build up a potential barrier.