| Nanomaterials display themselves with multidimensions and various shapes,satisfying different practical demands.There are a great number of methods for the preparation of nanomaterials,coming forth competitively and endlessly.Among them,electrochemical method is one of the most effective means in preparing nanoparticles and nanoporous materials for its advantages like simple,quick and green.The purpose of this thesis is to develop novel electrochemical methods for the facile fabrication of nanoparticles and three dimensional micro-nano structures of metals and their oxides.The main contents are summarized as follows:1.A novel electrochemical method has been proposed to fabricate tin and lead nanoparticles.By highly cathodic polarization in the alkaline solution,the bulk tin/lead metals can be directly dispersed into the corresponding metal nanoparticles(MNPs),with no needs of metal salts. The preparation process involves strong hydrogen evolution and possible formation/decomposition of unstable metal hydrides.SEM and XRD were used to characterize the as-prepared nanoparticles.At the same time, three-dimentional(3D) metal porous films can be obtained by self-assembly of the produced nanoparticles with the dynamic template of hydrogen bubbles.3D porous PbO2 can be also obtained by electrooxidation of the prepared 3D porous lead. 2.Through simple heat treatment,the prepared tin/lead nanoparticles can be easily converted into their oxides,which were characterized by SEM and XRD.The Raman spectrum and Raman induced fluorescence of the oxides have also been investigated.3.The oscillatory electrodissolution of tin in alkaline solution and the formation of three dimensional micro-nano structures of tin oxides in the anodic dissolution have been researched.Herein,the cyclic voltammetry based criterion was examined,the oscillatory mechanism was discussed,and the behavior of electrocrystallization nucleation was studied.
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