Fig. 2. (A) PL spectra of TTS in THF/water mixtures with different water fractions (f_w). (B) Plot of the relative PL intensity (I/I₀) versus the composition of the THF/water mixture of TTS. I₀ = emission intensity in pure THF solution. Concentration: 10 μM; excitation wavelength: 480 nm. Inset: fluorescence photographs of TTS in THF (f_w = 0%) and THF/water mixture with f_w = 90% taken under 365 nm UV illumination.