Abstract
In this study, the effects of atmosphere firing and pre-heating treatment on the characteristics of sodium titanates were investigated. The materials were successfully prepared from titanium tetraisopropoxide-sodium chloride (TTIP-NaCl) precursors assisted by organic templates (ethylene glycol and citric acid) via facile templating and hydrothermal methods. Sodium titanates were initially prepared by mixing a sodium precursor solution with a titanium precursor solution at a stoichiometric mole ratio of 1.6:1 under vigorous stirring. This was followed by pre-heating treatment via a hydrothermal method at 150 °C for 6 h and then calcination at 800 °C for 1 h in two different atmospheres including reduction and oxidation conditions. The same process was carried out in the synthesis of the other samples without the preheating treatment. The thermal behaviors of all the as-synthesized samples were evaluated. Meanwhile, the mineralogy and microstructures of all calcined samples were investigated. Both atmosphere firing and pre-heating treatment influenced the thermal behaviors of the as-synthesized sodium titanates, resulting in various sodium titanate types with different microstructures. To prepare the sodium titanates from TTIP-NaCl precursors, the pre-heating treatment and the reduction firing seemed to be the optimum conditions for the formation of sodium titanate, in order to produce Na2Ti6O13-type sodium titanates with rod-like particles in nanometer sizes.
