The Compound Of ITO,ZnS Nano-Powders And Preparation Of ZAO Ceramic

In this paper, the nano-powders of ZnO:Al(ZAO), In₂O₃:Sn(ITO) and ZnS have been prepared by the method of liquid phase-supercritical fluid drying(SCFD). The phase composition,morphological character and specific surface area of these powders are analyzed by the means of XRD, TEM and BET. And the technology of moulding and sintering of ZAO powder have also been initially investigated. The phase composition and fracture morphology of ZAO ceramic target are analyzed by XRD and SEM. The effect of adding La³⁺ ion and processing parameters of SCFD on the size and aggregation of ZAO powder is primarily discussed.From the analysis of experimental results, the following conclusions are achieved: 1 .Adding of La³⁺ ion can increase the specific surface area of ZAO nano-powders and decrease the size of ZAO nano-powders. Without heat treatment, the ZAO nano-powders which are less than 10 nm, and disperse well and have large specific surface area have been directly gained by SCFD method.2.ITO, ZAO and ZnS powders have been prepared successfully by the chemical coprecipitation-SCFD process.These powders are near sphericity and distributed uniformly.The size of them with large specific surface area is no more than 20nm.With the proper heat treatment.the hoped crystal structure of these powders can be obtained. The prepared ITO is a kind of substitutional solid solution which has the structure of ferromanganese of In₂O₃ after the crystallizing treatment at 700°C. The prepared ZAO is a kind of substitutional solid solution which has the structure of hexagonal wurtzite of ZnO after the crystallizing treatment at 650°C. 3.The technology of liquid phase-SCFD is that:(1)the proper pH value which can make every ions co-precipitation is between 9 and 11.(2)the aggregation of the nano-powders is restrained by adding surfacant as dispersionduring reaction process.(3)in order to obtain the critical temperature and critical pressure of a fluid, the...