Resin with short-range π-π stacking aggregates for an efficient photocatalyst

Abstract

A short-range π-π stacking aggregate photocatalyst (TE-resin) was facilely prepared by covalent grafting TE molecules onto crosslinked polystyrene-based macroporous resin, which displays short charge migration distance and efficient separation of electrons and holes, improved light absorption range and wettability , so TE-resin exhibits excellent photocatalytic activity and stability. • Short range π-π stacking aggregates were constructed by resin as a support. • Short-range π-π stacking aggregates display improved photocatalytic activity. • Short-range π-π stacking aggregates reduce the charge recombination efficiency. • Aggregate has good stability due to covalent bond connection between it and resin. Self-assembled supramolecular photocatalysts have aroused intensive attraction in extensive fields of solar energy conversion, water splitting and energy storage. However, the photocatalysts constructed by long range π-π stacking interaction usually display low photocatalytic activity because the holes and electrons recombine easily as they migrate along the long range π-π stacking structure. To overcome their shortcoming, for the first time, short-range π-π stacking aggregates were facilely prepared by covalent grafting 4′-(pethanediamine phenyl)-2,2′:6′,2″-terpyridine (TE) onto crosslinked polystyrene macroporous resin to form an efficient and stable photocatalyst. In the grafted resin, TE molecules linked to the resin molecules form a monolayer structure by short-range π-π stacking interaction along the polymer chains, which not only shortens the charge migration distance and reduces the charge recombination efficiency, but also efficiently improves light absorption range and wettability of the as-prepared photocatalyst. The above advantages endow the as-prepared photocatalyst with an excellent photocatalytic performance, for example, it affords a hydrogen evolution rate of 227.5 umol g -1 h −1 under UV–vis irradiation. Moreover, the covalent bond connection between TE aggregates and resin improves the stability of TE aggregates, enhancing their recycling. Overall, our work provides a convenient route for the preparation of efficient and stable short-range π-π aggregate photocatalyst assisted by resin for environmental and energetic applications.