Accurate quantification of TiO2(B)'s phase purity via Raman spectroscopy

Abstract

Bronze phase titanium dioxide (TiO₂(B)) could be a promising high-power anode for lithium ion battery. However, TiO₂(B) is a metastable material, so the as-synthesized samples are inevitably accompanied by the existence of anatase phases. It has been found that the TiO₂(B)'s purity is positively correlated with its electrochemical performance. Herein, we have established an accurate quantification of the TiO₂(B)/anatase ratio, by figuring out the function between the purity of TiO₂(B) phase in the high purity range and its Raman spectra features in combination of the calibration by the synchrotron radiation X-ray diffraction (XRD). Compared with the time-consuming electrochemical method, the rapid, sensitive and non-destructive features of Raman spectroscopy have made it a promising candidate for determining the purity of TiO₂(B). Further, the correlations developed in this work should be instructive in synthesizing pure TiO₂(B) and furthermore optimizing its electrochemical charge storage properties.