Conductive polymer supported and confined iron phosphide nanocrystals for boosting the photocatalytic hydrogen production of graphitic carbon nitride

Abstract

The development of earth-abundant cocatalysts with confined size on suitable conductive supports is of high importance for facilitating solar energy conversion using semiconductors. In this work, a green redox relay reaction between FeCl₃ and a pyrrole (Py) monomer was developed for the synthesis of g-C₃N₄–PPy–FeP, in which FeCl₃ realized the formation of PPy over graphitic carbon nitride, and the as-formed PPy confined and tightly supported Fe ions, which were then transformed into the nanosized FeP of diameter less than 5 nm. A highly porous morphology was obtained by inserting well-dispersed g-C₃N₄ into PPy, accompanied by conductive PPy and nanosized FeP acting as a mediator of charge carriers and high-performance cocatalyst, respectively. Consequently, optimal g-C₃N₄–PPy–FeP demonstrated a photocatalytic hydrogen evolution activity 6 and 20 times larger than that of g-C₃N₄ singly loaded separately with PPy and FeP, respectively, under visible light irradiation.