Use of the HighScore Plus software for an easy and complete quantification of the anatase, brookite, rutile, and amorphous phase content in TiO2

Abstract

X-ray diffraction is usually used to characterize TiO 2 -based materials, but to determine the percentage of amorphous phase by simple calculations and tools is not so straightforward. The present study analyzes the use of the software Highscore Plus to perform a complete structural characterization of a large set of TiO 2 -materials, commercial and prepared in our laboratory by sol-gel and hydrothermal methodologies, to evaluate not only the crystalline phases content, but also the amorphous phase content. CaF 2 is used as a reference material, and its crystallinity is assumed to be 100%. The comparison of the obtained results with those of the method developed in our research group by Cano-Casanova et al., based on the deconvolution of the XRD peaks of anatase, brookite, and rutile, have shown that the results of both methods are very similar, and Highscore Plus software can definitively be used for an easy determination of the amorphous phase content in titanium dioxide, even for materials with the three crystalline phases, rather overlapping peaks, and/or with a high amorphous phase content, which cannot be easily characterized by the method by Cano-Casanova el al. Thus, amorphous phase contents ranging from 5-51% are obtained with the Highscore Plus method, in contrast with 8-47% for the previously developed methodology. Our study has also highlighted the possibility of using the BET surface area of TiO 2 -based materials for an easy estimation of the percentage of amorphous phase. The need for a detailed (and easy) structural characterization of inorganic materials motivates this research. The content of anatase, rutile, brookite, and amorphous phase content can be determined in a wide number of TiO2 with different structural and textural properties, synthesized by sol-gel or hydrothermal methods. The software Highscore Plus can be used for such detailed structural characterization with results in very good agreement with those of previous quantification methods, and avoiding some limitations of previously published methods. • Amorphous phase content determination in TiO 2 also containing 3 crystalline phases • Highscore Plus software for a complete structural characterization from XRD data • It overcomes the limitations of the Cano-Casanova et al. quantification method • Applicable to TiO2 with overlapping peaks, and/or with high amorphous phase content • TiO2 with amorphous phase contents ranging from 5-51% have been fully characterized