fig3

Figure 3. (A) Schematic showing the synthesis of chiral SiO₂ nanofibers using PEI/tart templates. (B, C) SEM images of (B) D-PEI/tart and (C) D-PEI/tart@SiO₂. (D, E) High-magnification SEM images of (D) D-PEI/tart@SiO₂ and (E) L-PEI/tart@SiO₂. (F) CD spectra of D-, L- and DL-SiO₂. (G) CD spectra of D-, L- and DL-SiO₂ absorbed with tetrakis(3,5-hydroxyphenyl)porphyrin. This figure is used with permission from John Wiley and Sons^[34]. (H) TEM image of D-SiO₂ sol derived from D-SiO₂ nanofibers: (I) VCD (left) and IR (right) spectra of D-SiO₂ and L-SiO₂ sol. This figure is used with permission from the Royal Society of Chemistry^[36]. (J) A schematic proposal for the formation of chiral SiO₂ on PEI/tart templates. PEI: Polyethyleneimine; SEM: scanning electron microscopy; CD: circular dichroism; VCD: vibrational circular dichroism.