Highly efficient removal of organic pollutants by ultrahigh-surface-area-ethynylbenzene-based conjugated microporous polymers via adsorption-photocatalysis synergy

Two types of conjugated microporous polymer photocatalysts inherently possessing a high surface area (up to 1265 m(2) g(-1)) have been synthesized via Sonogashira-Hagihara cross-coupling polycondensation and applied for the removal of different organic contaminants (rhodamine B, phenol and tetracycline) via adsorption-photocatalysis synergy. The study on the photocatalytic performance and mechanism demonstrated that the specific surface areas and the backbone structures of the polymers had a great influence on the photocatalytic performances. A higher specific surface area and an increased adsorption efficiency for pollutants contributed to the enhanced photocatalytic activity. The optical and electrochemical characterization studies revealed that compared with its counterpart with a network structure, the linear polymer (based on 1,4-diethynylbenzene) showed a narrower band gap and a higher photogenerated charge separation efficiency due to its better extended conjugated system, which boosted its photocatalytic activity. The above features made the polymers exhibit superior adsorption-photocatalytic activity compared with the reported photocatalysts. This work highlights the potential of developing porous organic semiconductors as highly efficient photocatalysts for environmental remediation.