Figure 10.

a FTIR spectra of the titanium oxide nanoparticles (black line, sample 2 in Table 1) and microtubes (red line, sample 4 in Table 1) with significant OH signature as indicated by free OH groups around 3400 cm−1 and molecular water around 1720 and 1630 cm−1(cf. text). Note the microtubes were more OH-signified than the nanoparticles but did not change into crystalline titanium hydrates (cf. text) upon dwelling in water for a week. b Raman spectra of the titanium oxide nanoparticles (black line, sample 2 in Table 1) and microtubes (red line, sample 4 in Table 1) showing the bands of rutile at 614, 443, 248, and 144 cm−1 in sample 2 change to 606, 416, 264, and 414 cm−1, respectively, and the band at 344 cm−1 for Ti2O3 in sample 2 is ambiguous for sample 4. The monoxide TiO cannot be detected since it is not Raman active (cf. text)

Huang et al. Nanoscale Research Letters 2010 5:972-985   doi:10.1007/s11671-010-9591-4