The effect of molecular structure and fluorination on the properties of pyrene-benzothiadiazole-based conjugated polymers for visible-light-driven hydrogen evolution

The development of highly efficient organic photocatalysts for water splitting into hydrogen is one of the key challenges in materials chemistry. Herein, we have designed and synthesized a series of conjugated polymers with either a one- or three-dimensional framework consisting of pyrene and benzothiadiazole with different numbers of fluorine substitutions (0 or 2). The effect of molecular structure and fluorine substitution on their catalytic activity was investigated. It was found that the linear non-fluorinated polymer L-PyBT exhibited the highest hydrogen evolution rate up to 83.7 μmol h−1 under visible light irradiation among the prepared polymers because of its broad light absorption, suitable energy bandgap, and enhanced charge generation and separation process.