Solution-state assembly of intrinsic broadband white-light emitters

Stanford researchers have patented a family of white light emitting perovskites with photoluminescence quantum efficiencies (PLQEs) of up to 9%, which show stable emission over at least three months of continuous irradiation. Upon near-ultraviolet excitation, two new Pb–Cl and Pb–Br perovskites emit broadband 'cold' and 'warm' white light, respectively, with high color rendition. Emission from large, single crystals indicates an origin from the bulk material and not surface defect sites. Advancing hybrid perovskite technology these white-light emitting phosphors demonstrate high color rendition, tunable chromaticity, and sustained emission stability over one week of continuous irradiation. Overcoming critical solid-state lighting (SSL) limitations, these materials offer room-temperature synthesis, binder-free solution-state film deposition, high color rendition, tunable chromaticity, and sustained long-term performance.

Figure 1 - Broadband white-light photoluminescence (PL) from a single crystal of (EDBE)[PbBr4] under near-UV irradiation.
(Image courtesy the Karunadasa Group)

Stage of Development – Proof of Concept