Figure 11.

(a) Schematic of donor and acceptor QDs coated with 15-crown-5, which selectively interacts with potassium ions. Schematic is not drawn to scale; (b) PL spectra of the isolated donor and acceptor QDs (green and red lines, respectively). PL spectra of mixed QD populations after adding 2ⁿ × 3.6 μM of KClO₄ (black lines). Reversibility demonstrated by adding 1 M Na⁺ after the n-th addition of K⁺ (orange line). Absorption of spectrum of the QD mixture shown overlaid behind the PL spectra (black line); (b) reprinted with permission from [89].