Figure 3
Reversible thermochromic properties of PDA-Azo-TEG nanotubes. (a,b) Raman (a) and UV-Vis absorption spectra (b) of nanotubes before (black curve, DA-Azo-TEG) and after (blue curve, PDA-Azo-TEG) 254 nm UV irradiation with intensity of 1 mW/cm2 for 10 min. The insets in panel b indicate the photographs of corresponding nanotube dispersions. (c) Raman spectra of PDA-Azo-TEG dispersions before heating (black curve), right after heating (red curve) at 90 °C, and after cooling (blue curve) to room temperature. (d) Reversible thermochromism of PDA-Azo-TEG coated films over multiple runs of heating to 90 °C for 5 seconds and cooling to room temperature for 5 seconds. The blue and red dots indicate absorbance at 650 nm at the heating and cooling conditions, respectively.
