Intramolecular hydrogen bonds assist in controlling the quantum well distribution in quasi-2D perovskites for efficient pure-blue perovskite light-emitting diodes

Use of an o -F-PEABr ligand containing an intramolecular hydrogen bond can effectively suppress low- n phases in quasi-2D perovskites. The resultant light-emitting diodes achieve a maximum efficiency of 7.55% and a pure blue emission at 475 nm.