Protic acids as third components improve the phosphorescence properties of the guest-host system through hydrogen bonds

Abstract

A new phosphorescence guest–host doped system was constructed, protic acids are selected as the third component. Protic acids can greatly enhance the phosphorescence emission of the doped system and induce the doped system to produce a stimulus–response function. • A three-component organic doped system with RTP characteristics are developed. • Third component greatly improve the RTP activity by forming hydrogen bonds with the host. • Third component make the doped system has reversible alkali stimulus-responsive function. • Providing a universal strategy for constructing the multi-component doped systems with better RTP property. Host-guest doped materials have attracted widespread attention. However, most of the doped materials are two-component systems, and the phosphorescence properties and functions need to be further improved. Herein, diphenyl sulfoxide was selected as the host, and 1,3-diphenylbenzofuro[2,3-c]pyridine was designed as the guest to construct a new phosphorescence doped system. Importantly, water, phenol, benzoic acid, and phenylboronic acid are selected as the third component to form hydrogen bonds with the host molecules, the hydrogen bonds can improve the phosphorescence performance of doped materials. The phosphorescence quantum yields are increased from 4.3 % of the two-component to 18.8% −28.5 % of the three-component, and the phosphorescence lifetimes are increased from 147 ms to 235–308 ms. Moreover, the addition of the third component makes the phosphorescence of the doped system has a reversible alkali stimulus–response function. This work provides a universal strategy for constructing the multi-component doped systems with better phosphorescence performance or more phosphorescence functions.