And Electrochemical Properties Of Porous Metal Film Was Constructed

Porous metal materials are comprised of metal skeletons and pores, which indicate a mass of pores with a regular or random distribution existing in metal materials. Porous metals possess the low density, high strength, excellent absorptivity of energy and large specific surface area, and have been widely applied in catalysis, sensor and heat exchange fields. In inertial confinement fusion (ICF) experiments, the internal surface of double shell targets should be a porous microstructure. Hence, for the application of nano porous metals in double shell targets of ICF experiment, it is important that the internal surface of target should be a controlled porous structure, low density, large specific surface area. In this project, we will prepare the porous metal films applied potentially in ICF experiments.The prepared methods and corresponding principles of nano porous metals by hydrogen bubble templates and dealloying based on impulse corrosion have been summarized in this thesis, and an overview on the research and application of nano porous metals have also been introduced. The porous copper, nickel and iron films were prepared using hydrogen bubbles as the templates under a high current density, and the porous copper films were manufactured by the dealloying method employing the single and double impulse corrosion. The microstructures and performance of nano porous metal films were characterized and analysed by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectrometer (EDS) and electrochemical workstation, respectively.Two methods were used to prepare the porous metal films in this thesis. Firstly, the porous copper, nickel and iron films were prepared using hydrogen bubbles as the templates. The effects of deposition conditions and annexing agents on surface morphology and pore wall structure of3D porous metal films were investigated. The results showed that the porous copper film with good surface morphology can be derived from the copper plating bath adding0.2wt%sodium dodecyl sulfate (SDS) as an anionic surfactant, and the addition of0.05M H2SO4to nickel plating bath lead the decrease of the pore size of porous nickel film and a thin pore wall. In addition, the pure porous iron film was firstly prepared, and a spiral growth mode of grains in porous iron film was presented in the iron plating bath with the addition of H2SO4.Secondly, the dealloying method with electrochemical corrosion was used to prepare porous copper films. The Cu-Zn alloy was corroded in an impulse power source. The corrosion investigation included single and double impulses. The effects of impulse conditions and additive agent on porous coatings were discussed in detail. It is worth to note that the mist-like porous copper films with nano-size pores and thin pore wall were prepared in the single impulse corrosion. However, the porous copper thin derived from the double impulse corrosion presented a crisscross and disorder surface morphology, a deep pore structure, and an asymmetrical pore size distribution with the center value of about200nm. Some large copper particles were observed in the surface of porous copper films. The surface morphology was improved through the addition of EDTA and HCI to electrolyte solution. Additionally, the preparation of Cu-Zn plating coatings was discussed details. The excellent Cu-Zn coating suiting for the dealloying experiment was obtained from the electroplating bath with the Cu2+concentration of0.05M and the Cu2+/Zn2+mole ratio of1:2.