Inorganic Solids of CdSe Nanocrystals Exhibiting High Emission Quantum Yield

A general strategy for the assembly of all-inorganic light-emitting nanocrystal films with emission quantum yield in the 30–52% range is reported. The present methodology relies on solution-processing of CdSe nanocrystals into a crystalline matrix of a wide band gap semiconductor (CdS, ZnS), which replaces the original molecular ligands on nanocrystal surfaces with an inorganic medium. Such matrices efficiently protect nanoparticles from the surrounding environment and preserve the quantum confinement of electrical charges in embedded CdSe NCs. In addition to strong emission, fabricated films show excellent thermal and chemical stability, and a large refractive index, which avails their integration into emerging solid-state nanocrystal devices, including light-emitting diodes, solar concentrators, and quantum dot lasers.