Building an electron push–pull system of linear conjugated polymers for improving photocatalytic hydrogen evolution efficiency

Abstract

A series of linear conjugated polymers with different acceptor units has been synthesized and applied as photocatalysts for hydrogen evolution from water splitting. It was found that the introduction of nitrogen atom into the polymer skeleton could efficiently improve the photocatalytic performance due to the improvement in charge carriers’ transport and separation, and the enhanced interfacial wettability from the hydrogen-bonding interaction between nitrogen atom and water molecule. The replacement position of nitrogen atom also has a big influence on the photocatalytic performance due to the enhanced internal dipole orientation. A high hydrogen evolution rate of 18.7 µmol h−1 was achieved by PyPm with strong acceptor unit of pyrimidine. The results demonstrate that the construction of an electronic push–pull system is an efficient strategy to produce linear conjugated polymer photocatalysts with high photocatalytic performance.