Surface passivation of semiconductor quantum dots is essential to preserve their efficient and robust light emitting properties. While molecular ligands in colloidal systems can retain efficient emission, core/shell structures are usually required to approach photoluminescence quantum yields near 100% in solution. Most electronic applications, however, require high performance in the solid state, where quantum yields are generally lower than in colloidal suspensions. By using a lattice matched (mismatch = 0.5%) lead halide perovskite matrix, we achieve shell-like passivation of lead sulfide QDs in crystalline films, leading to high solid state infrared quantum yields. These structures are made from a simple one-step spin coating process of an electrostatically stabilized colloidal suspension. Photoluminescence and transient absorption spectroscopy indicate rapid energy transfer between the perovskite matrix and the QDs, suggesting an interface with few trap states. In addition to housing the efficient infrared QD emitters, lead halide perovskites themselves have good carrier mobilities and low trap densities, making these solution-processable heterostructures an attractive option for electrically pumped light emitting devices.

Lead sulfide quantum dot/lead halide perovskite heterostructures from a single colloidal suspension

251st National Meeting (2016)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.