Research On The Selective Dealloying Of Few Alloy And Hydrogen Uptake Corrosion Of Zirconium

Nuclear energy is an important part of the new energy, and nuclear material is the basis of the use of nuclear energy. Although nuclear energy show a bright future, but technological bottlenecks in the field of nuclear materials are hampering its development. The harsh working environment in the Fusion reactor has strict requirement on the Plasma Facing Materials, and the corrosion resistance of Zirconium alloy cladding determines the security of the Fissile reactor system. To break the technical bottlenecks of those two kinds of nuclear materials, tungsten nano-metal building and zirconium hydrogen permeation behavior were studied.Dealloying method was employed in achieving the nanoporous structure, and a new kind a nanoflake structure of WO3was obtained on the FeW amorphous film unexpectedly. The morphology, phase structure and electronic band structure of nanoflake WO3were studied. As a N-type semiconductor, nanoflake WO3exhibited a significantly increased photocurrent in0.5M sulfuric acid. The double layer capacity, Mott-Schottky, UV-Vis, and XPS were examed to evaluate the specific surface area, carrier density, electronic band structure and the surface element.A new kind of oxygen evolving catalyst Co-Pi was combined with nanoflake WO3to achieve more significant photoelectrochemical water splitting performance. But a serious current decline led us to the result of photochemical corrosion between WO3and PO43-, which resulted in a new phase of W18P2O59on the nanoflake surface. XRD, Raman, and EIS data confirmed the decline of photoelectric conversion efficiency and the increase of ion transfer resistance.Three factors of vacuum annealing, EDTA solution, and controlled bias potential were introduced in preparing the W nanoporous structure, and it was achieved by470℃,0.25M EDTA, and-0.6V. Bias potential was determined by Tafel and polarization curves, and the oxidation peaks of Fe and W were recorded by Cyclic Voltammetry plots. This pure W structure was examined by HRTEM and the SAED pattern.For the hydrogen uptake behavior in Zirconium and Tungsten, this paper focuses on the synthesizing and electrochemical testing. Electrochemical parameters were recorded after the cathodic hydrogen permeation at different cathodic current density. By a comparision between data of OCP, Tafel, and EIS before and after the hydrothermal oxidation of hydrogenated Zirconium, hydrogen was found to be easily introduced into metal base and tend to form a compound. Besides, the positive shift of corrosion potential and the enlarged capacitive loop confirmed that hydrogenation promoted the oxidation of Zirconium.