Fig. 1.

Characterization of the fabricated SiTQD nanocomposite. TEM images of (a) single SiO₂ core, (b) SiQD, (c) SiDQD, and (d) SiTQD nanocomposite. TEM images of multiple (e) SiO₂ NPs and (f) SiTQD NPs, and their corresponding SEM images (g) and (h), respectively. (i) EDS elemental (Si, Cd, Se, Zn) mapping images of a SiTQD NP. Zeta potentials (j) and fluorescence emission spectra (k) of the synthesized NPs from each stage. The inset in (k) displays the photographs of these NPs solution under visible (upper) and UV light (lower). (e) Fluorescence images and intensities of SiTQD at different pH values. (l) Photograph of SiTQD NPs at various pH values under UV light (upper) and their corresponding fluorescence intensities at maximum emission wavelength (lower).