Photoluminescent Aerogels from Quantum Wells

Highly porous self-supported three-dimensional aerogel monoliths are synthesized from strongly quantum confined quantum wells, namely, 5 monolayer thick CdSe and CdSe/CdS core/crown nanoplatelets. The aerogels are synthesized by hydrogelation of the aqueous quantum well solutions and subsequent supercritical drying. The aerogels are optically characterized by UV–vis absorption spectroscopy, emission spectroscopy, and photoluminescence (PL) decay analysis. Morphological and structural characterizations are achieved by transmission electron microscopy, scanning electron microscopy, and X-ray diffractometry. The macroscopic aerogels exhibit extremely low densities of 0.038 ± 0.007 g·cm –3 and a significantly high specific surface area of 219 m 2 ·g –1 with nearly entirely (111) as the exposed crystal facet. Moreover, the aerogels feature properties related to quantum confinement comparable to those of their original building blocks with photoluminescence quantum yields up to 10.3%.