Pressure-Tailored π–π Stacking in Dimers Enhances Blue Photoluminescence in Boron-Based Organic Molecules

Abstract

Organic materials with exceptional blue photoluminescence have emerged as a captivating class of materials, exhibiting promising applications as full-color display and solid-state lighting. However, the photoluminescence quenching is a largely unsolved problem towing to the strong π–π interaction in the aggregation effect or the electrostatic repulsion. Herein, a strategy to harvest the remarkably enhanced blue emission in phenylboric acid molecules with intricate hydrogen bond networks through pressure treatment engineering is proposed. Intriguingly, the photoluminescence quantum yields of pressure-treated phenylboric acid experiences a significant enhancement from 2.3 % to 31.5 %, which shows bright blue emission. The inhibition of benzene ring vibration and the reduction of π–π stacking interaction originating from the offset stacking mode are highly responsible for the enhancement of blue photoluminescence. This work demonstrates the feasibility of modulating molecular stacking patterns to achieve efficient emission and presents a momentous strategy for improving the optical properties of blue organic materials.