A Photoresponsive Azobenzene-functionalized Covalent Organic Framework

Covalent organic frameworks(COFs) with high specific surface area, regular structure, and modifiable pore channels, are crystalline porous organic polymers and have been widely used in various fields. Azobenzene derivatives with light isomerization characteristics are important stimulus-responsive materials. Herein we report a method of postsynthetic modification for the preparation of photothermal responsive azobenzene-functionalized COF, denoted as JUC-501 (JUC = Jilin University China) , which based on introducing small azobenzene molecules into the channels of COF (JUC-500) . Under ultraviolet irradiation and heating conditions , the COF with azobenzene in the pores will undergo reversible cis-trans isomerization reaction and exhibits excellent reversible capture and release properties for methyl orange (MO) .