Phase formation study of magnesium titanate nanomaterial with polyethylene glycol template

Abstract

The formation of geikielite (MgTiO3, abbreviated as MT) nanomaterial with an addition of polyethylene glycol (PEG)-1000 during synthesis is reported. The synthesis of MT was carried out by means of the dissolved-metal mixing route with PEG-1000 as a template. Prior to the synthesis, Mg and Ti powders, as the raw materials, were independently dissolved in 37% HCl to form MgCl2 and TiCl4 solutions, respectively. Meanwhile, PEG gels with various weights, namely 0.5; 1.0; 1.5; 2.0; 2.5g, were prepared by heating at around 30-40 °C. The solutions and PEG gels were then mixed for 5 hours and dried to temperatures of about 105-110 °C to produce powders with five different PEG compositions. Each of the dried powder was calcined at 600 °C for 1 hour. A sample with no PEG was also prepared following a similar procedure for comparison. The calcined powder was characterized by XRD and to which the data was then quantitatively analyzed by appliying Rietveld method using Rietica software. Results showed that introducing PEG-1000 leads to the formation of MgTi2O5. Further quantitative analysis showed that in general addition of PEG increased the MT weight fraction. Addition of 2.5g PEG increased MT content by more than 12%. The role of PEG on the templation is discussed. TEM micrographs are presented to support the discussion.