TEM images, UV–vis absorbance spectra, and PL emission spectra of TiO
NPs. TEM images of as-synthesized GalA-TiO2 NPs (a) and Dpa-TiO2 NPs (b). UV–vis absorbance spectra (c) and their photos (inset: from left to right: bare, Dpa- and GalA-TiO2 NP aqueous solutions). PL emission spectra (λ
= 350 nm) (d) of the NP aqueous dispersions.