CdSe-based Quantum dot in perovskites: from emissive thin films to single photon source

Research on hybrid perovskites for photovoltaics has been booming since 2009, evolving from the first reported efficiency of 3.8% for a solar cell using perovskites as photo-active materials to an efficiency of 25% in 2021. Since then, the literature and potential applications of hybrid perovskites have grown exponentially. In addition to their remarkable optical and transport properties, this success of hybrid halide perovskites is explained by them being easy to process and allowing the creation of multi-scale compounds (from bulk to thin-films and quantum dots (QDs)), as well as by their compatibility with industry-scale soft-chemistry processes.

I will present the doping of crystalline methyl–ammonium lead bromide perovskite (MAPbBr3) films with CdSe/CdZnS core/shell quantum dots (QDs), using a soft-chemistry approach that preserves their high quantum yield and other remarkable luminescence properties. Our approach produces MAPbBr3 films of around 100 nm thickness, doped at volume ratios between 0.01 and 1% with colloidal CdSe/CdZnS QDs whose organic ligands were exchanged with halide ions to allow for close contact between the QDs and the perovskite matrix.

At high CdSe/CdZnS QD doping levels, this work thus opens a route to hybrid solar concentrators for visible-light harvesting and hybrid-based LEDs, while a low degree of doping could yield hybrid single-photon sources than can be embedded in field-effect devices for single-charge control, which would allow the construction of nanophotonic devices via low-cost solution-processing techniques as an alternative to solid-state quantum dots.