Fluoro-polymer/TiO2 based photocatalysts for hydrogen generation

Abstract

In view of limited number of studies on photoreforming of synthetic polymers, herein, a series of new glycopolymers are synthesized via RAFT polymerization to obtain diblock copolymers containing fluorinated and non-fluorinated segments in the glucopyranoside. These glycopolymers are used as probes to investigate photocatalytic reactions at different pH values of the modulated TiO2 photocatalyst. Through structural and surface characterizations, photocatalytic activities are investigated. Fluoro-polymers with deacetylated glucose, hydrophilic segment, PGD such as PPFPM-b-PGD and PPFBM-b-PGD could synergistically increase hydrogen generation rate up to 1368 μmol g-1h−1 and 1549 μmol g-1h−1 with quantum yields of 3.34 % and 3.79 % compared to non-fluoro glycopolymers. The presence of both fluorinated and non-fluorinated groups in diblock copolymers enhanced the rate of photocatalytic hydrogen generation compared to the homopolymer. The accelerated photo-reforming is attributed to in-situ fluorine-doped TiO2 along with high affinity and activation of water molecules. These polymers can generate hydrogen via photo-reforming process.