ABSTRACT
More extensive experiments regarding the one-step method have been carried out by E. Ruckenstein and C. T. Cheung, who identified the sequential transformations that occur in the formation of various Thallium-Based High-Temperature Superconductive Oxides phases and studied the kinetics of the processes. Compared with the one-step method, the multistep method has numerous advantages, such as reduction in the extent of powder melting, less Thallium loss, and better compositional homogeneity, to name a few. The successful application of the wet-process method to the fabrication of the single-phase Thallium-based superconductive powders requires much more effort in developing new solution-precipitation systems that will allow the precise control of the precipitate composition, as well as in seeking the optimum calcination procedure. Subsequently, either the solution is dried directly or a precipitating agent such as citric acid is introduced into the solution to form insoluble salts of the constituent elements, which coprecipitate from solution.
