Preparation of nanostructured ZrTiO4 by solid state reaction in equimolar mixture of TiO2 and ZrO2

Abstract

Key words mechanical milling, high-resolution electron microscopy, x-ray diffraction, in situ high temperature Raman spectroscopy, nanocristalline zirconium titanate. PACS 81.05.Je, 81.07.-b, 81.20.Ev A solid state reaction in an equimolar mixture of TiO 2 and ZrO 2 was achieved by high-energy ball-milling. The ball-milling first induced the transformation of anatase TiO 2 to high-pressure phase TiO 2 (II). Nanosized ZrTiO 4 phase was formed from TiO 2 (II)/ZrO 2 solid solution by prolonging milling. The finishing of the solid state reaction towards ZrTiO 4 ceramic is investigated in situ at high temperature (< 1100°C) by RS. Reaction is completed at a temperature much lower than reported in literature (1400 -1600°C).

Mechanochemistry: opportunities for new and cleaner synthesis

“…[79] The synthesis temperature of ZrTiO 4 could similarly be reduced from 1400°C to 1100°C. [80] This mechanochemical activation followed by sintering has also been used in the synthesis of MgTa 2 O 6 , [81] and the aurivillius phases Bi 4 Sr n-3 Ti n O 3n+3 (n = 4,5). [82] An alternative mechanochemical approach involves providing a thermodynamic driving force to the reaction.…”

Low-temperature Oxidation of Carbon Monoxide on Co/ZrO2

“…Figure 6 shows the spectra obtained on the powdered 10%Co/ZrO 2 catalyst, ZrO 2 support, and bulk [26].…”

Structure and electrical conductivity of porous zirconium titanate ceramics produced by mechanochemical treatment and sintering

“…The milling was performed in air by planetary ball-mill (Fritsch, "Pulverisette 6") with vial and balls made of zirconia. The powder-to-ball weight ratio was chosen to be R=1:10 to avoid contamination due to wearing of milling media [11]. The samples were milled with the rotation speed of 500 rpm for 7 h, since at this milling time began the solid state reaction toward ZrTiO 4 [10].…”

“…Recently, we have shown [10,11] that the preparation of ZT ceramics from the ball milled precursor decreases the sintering temperature and thus reduces the energy necessary for solid state synthesis of pure ZT ceramics. In fact, the powder precursor produced by highenergy ball milling of TiO 2 and ZrO 2 , facilitates the solid state reaction toward ZrTiO 4 even before heat treatment [10].…”