Paisan Setasuwon and Suphakan Kijamnajsuk

pp. 787 - 790

Abstract

      Powder size is a major factor determining the characteristics of processing variables and end-products of ceramic materials. Conventionally, common particles sizes are employed in the micron range. It is now realized that better materials could be obtained through the use of submicron or nanoparticles, but they are available at much higher cost, leading to costly end-products.
      The effects of molten salt synthesis (MSS) employing two different salt systems, alkaline chloride and sulfate, were investigated. Employing a mixture of NaCl-KCl, the obtained crystals could be as large as tens of microns. The shape of crystals was thin platelet. However, MSS using Na₂
SO₄-K₂SO₄ yielded a very different result. The obtained particles were
very small, in the submicron range. Moreover, the synthesizing temperature for Bi₄Ti₃O₁₂ was just 650°C, much lower than 850°C of MSS with NaCl-KCl. Therefore by employing MSS, it is possible to produce either Bi₄Ti₃O₁₂ crystals tens of microns in size using alkaline chloride system or very fine particles in the submicron range using an alkaline sulfate system.