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.