Toluene

The 8.6 nm NCs
were synthesized following the method reported in ref (51 (link)). In a 25 mL three-neck
flask, PbBr₂ (55 mg, ABCR, 98%) was degassed three times,
suspended in 5 mL of ODE, and degassed again three times at room temperature.
The suspension was fast heated up to 180 °C, when the temperature
reached 120 °C; 0.5 mL of OA and oleylamine (0.5 mL, OLA, Strem,
97%, distilled) was injected. At 180 °C, preheated to about 100
°C cesium oleate solution in ODE (0.6 mL) was injected. The reaction
mixture was cooled immediately to room temperature with an ice bath.
The crude solution was centrifuged at 20 130 relative centrifugal
force (rcf) for 5 min. The supernatant was discarded, and the precipitate
was dispersed in hexane (0.3 mL, Sigma-Aldrich, anhydrous, 95%). The
solution was centrifuged again at 13 750 rcf for 3 min, and
the precipitate was discarded. Then, OLA/OA ligands were exchanged
by didodecyldimethylammonium bromide (DDAB) treatment. Then, 0.3 mL
of hexane, toluene (0.6 mL, Sigma-Aldrich, anhydrous, 99.8%), and
DDAB (0.14 mL, 0.05 M in toluene, Sigma-Aldrich, 98%) were added to
the supernatant and stirred for 1 h, followed by destabilization with
ethyl acetate (1.8 mL, Sigma-Aldrich, 99.9%), centrifuging at 20 130
rcf for 3 min and redispersion in 0.6 mL of toluene. Synthesis of
5.3 nm CsPbBr₃ NCs was adopted from ref (50 (link)) followed by DDAB treatment.