Preparation Of Nano-Thin Film And Block Of La_0.6Sr_0.4MnO₃ And Study Of Their Performances

In recent years, nanomaterial research raised a revolution in the field of material science. Nano-thin film and Nano-building block materials are one of the important parts of nanomaterials. The successful preparation of the high quality Nano-thin film and Nano-building blocks is the key to the wide-range application of this kind of materials. The perovskite compound oxide has stable structure and outstanding performance. Its Nano-thin film and Nano-building block with multiplex component and complex structure may be prepared successfully according to its mineralization mechanism. It has aroused an universal interest.In this thesis, the perovskite La_0.6Sr_0.4MnO₃ extension thin film was prepared on the slide glass base using sol-gel method and dip-coating technology.The thermal decomposition course of metal carboxylate gelatin has been analyzed using the TG/DTA technology. The phase analysis has been carried on through XRD, and its crystal grain size has been calculated. The appearance characteristic of this thin film has been observed using AFM. The results show that, the La_0.6Sr_0.4MnO₃ thin film forms at 570℃, it is rhombohedra and its average crystal grain size is 10.816nm. We may see from the AFM Image that the film with four layers is more homogeneous; the surface roughness is less than 35nm. The average thickness of the thin film(four layers) obtained from the step meter is 98.8nm.The electrochemistry performance of the thin film has been tested through the polarization curve. We discovered that the electrode reaction was easier due to the existence of the film and the catalytic activity of liberate oxygen becomes higher with the film's layer increases. The degradation experiment of various water-soluble dyestuff has been performed using the La_0.6Sr_0.4MnO₃ film by photo-catalytic methods. The research has indicated that, this nano-thin film has good photocatalysis effect, and the decoloration rates of Acid red A,Acid orangeâ…¡,Weak-acid yellow C-3GN, Direct green BE, Weak-acid blue C-RL have reached to 95.56%, 89.70 %, 97.56 %, 98.40 % and 81.16 % respectively in 9h.The perovskite La0.6Sr0.4MnO3 block was prepared using the powder metallurgy technology combined with high temperature and high pressure method. The influence of different pressure and different temperature on the block's grain size and the crystal structure has been discussed. The change tendency of density, hardness, phase, surface topography and resistivity of the Nano-building block prepared under various conditions has been preliminary studied.