Synthesis of pure and calcia stabilized ZrO2 via liquid mix technique and their characterization

Abstract

Partially and fully stabilized zirconia is one of the most important high tech (high performance) materials used in many diverse fields such as chemical gas sensors [1], high temperature refractories [2], etc. Much experimental work is being carried out to synthesize highly reactive, uniform submicrometre particle size distribution of pure and stabilized zirconia by using the following conventional preparation techniques such as attrition milling [3], reaction sintering [4], coprecipitation and decomposition of the sol-gel [5, 6], hydro-thermal processes [7], spray-ICP technique [8], and arc melting [9]. These techniques have some advantages and disadvantages. For example, attrition milling suffers from many drawbacks. Firstly, it lacks uniformity and homogeneity of the product. Secondly, this technique involves ball milling over an extended period of time which introduces lattice defects and strains in the materials. In the case of the coprecipitation technique, the control of the pH value is very critical. Other techniques are rather laborious and costly.We attempted to prepare pure as well as 5 mol % calcia-doped zirconia by a novel technique used successfully in our laboratory to synthesize other high tech reactive products [10][11][12][13]. This method is known as the liquid mix technique. Full details of this method have been discussed elsewhere [14] but a brief outline is given below. The required amount of calcium carbonate AR grade (Loba

Electrolytic ZrO2 Coatings: II. Microstructural Aspects

“…According to the Ellingham diagram (14), graphite oxidizes under the present firing conditions to form CO gas, but no reaction with the zirconia is expected to occur. Formation of undoped zirconia via solution by different techniques and crystallization of the lowtemperature polymorphs of zirconia by firing at the relatively low temperature are well documented in the literature (15)(16)(17). The presence of the t polymorph is related primarily to the crystallite size effect (18,19), by which the tetragonal phase may be retained metastably at room temperature.…”

Zirconia/Silica Sol−Gel Catalysts: Effect of the Surface Heterogeneity on the Selectivity of 2-Propanol Decomposition

“…Because of this, zirconia/silica mixed oxides are reported as alternative composites for the stabilization of zirconium oxide. The zirconia stabilization can be done by impregnation of thermally ressitance supports using ZrOCl solutions − or by gels synthesis using alkoxides. , …”