Conjugated Cationic Pp-x Formed on g-C3N4 for Photocatalyzed Water Splitting.

ABSTRACT

Polycationic Pp-x@g-C3N4 composite was synthesized through an in situ polymerization process of N-alkylpyridinium acetylenic alcohol bromide (p-x) above the surface of g-C3N4. The structure of p-0 and the Pp-x@g-C3N4 properties were checked by modern technologies. Photocatalytic tests of Pp-x@g-C3N4 in water splitting unveiled much better Pp-x@g-C3N4 hydrogen evolution activities by comparison with both g-C3N4 and Pp-0. The hydrogen production by Pp-0@g-C3N4 was 1654.5 µmol h-1 g-1, which is ∼26- and 22-fold greater in relation to what g-C3N4 and Pp-0 produced (62.7 and 75.0 µmol h-1 g-1, respectively), suggesting strong bilateral and synergistic interactions of g-C3N4 with Pp-0. Although the lengthening methylene chain in the polymers weakened the hydrogen generation ability of Pp-x@g-C3N4, the conjugated double bonds, solubilization, and dispersion of Pp-x polycationic surfactants made Pp-x@g-C3N4 superior to g-C3N4 in water splitting. Due to the readily available raw materials, a simple way of preparation (starting chemicals to p-0 to Pp-0@g-C3N4), high photocatalysis efficiency, light irritation stability, recyclable ability, and low toxicity, Pp-0@g-C3N4 is a good candidate for water splitting.