Networked Cages for Enhanced CO Capture and Sensing.

It remains a great challenge to design and synthesize a porous material for CO capture and sensing simultaneously. Herein, strategy of "cage to frameworks" is demonstrated to synthesize fluorescent porous organic polymer (pTOC) by using tetraphenylethylene-based oxacalixarene cage (TOC) as the monomer. The networked cages (pTOC) have improved porous properties, including Brunauer-Emmett-Teller surface area and CO capture compared with its monomer TOC, because the polymerization overcomes the window-to-arene packing modes of cages and turns on their pores. Moreover, pTOC displays prominent reversible fluorescence enhancement in the presence of CO in different dispersion systems and fluorescence recovery for CO release in the presence of NH·HO, and is thus very effective to detect and quantify the fractions of CO in a gaseous mixtures.