Blue-Green Color Tunable Solution Processable Organolead Chloride–Bromide Mixed Halide Perovskites for Optoelectronic Applications

• Published in: Nano letters Vol. 15; no. 9; pp. 6095 - 6101
• Main Authors: Sadhanala, Aditya, Ahmad, Shahab, Zhao, Baodan, Giesbrecht, Nadja, Pearce, Phoebe M, Deschler, Felix, Hoye, Robert L. Z, Gödel, Karl C, Bein, Thomas, Docampo, Pablo, Dutton, Siân E, De Volder, Michael F. L, Friend, Richard H
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 09.09.2015
• Subjects: Chlorides; Emission; Halides; Letter; Light-emitting diodes; Nanostructure; Optoelectronic devices; Perovskites; Tuning; disorder; narrow FWHM; chloride bromide perovskite; Blue perovskite LED; bandgap tuning
• ISSN: 1530-6984; 1530-6992; 1530-6992
• DOI: 10.1021/acs.nanolett.5b02369

Solution-processed organo-lead halide perovskites are produced with sharp, color-pure electroluminescence that can be tuned from blue to green region of visible spectrum (425–570 nm). This was accomplished by controlling the halide composition of CH3NH3Pb­(Br x Cl1–x )3 [0 ≤ x ≤ 1] perovskites. The bandgap and lattice parameters change monotonically with composition. The films possess remarkably sharp band edges and a clean bandgap, with a single optically active phase. These chloride–bromide perovskites can potentially be used in optoelectronic devices like solar cells and light emitting diodes (LEDs). Here we demonstrate high color-purity, tunable LEDs with narrow emission full width at half maxima (FWHM) and low turn on voltages using thin-films of these perovskite materials, including a blue CH3NH3PbCl3 perovskite LED with a narrow emission FWHM of 5 nm.