One-pot synthesis of an ultrafine Cu2O nanocrystal/porous polymer heterostructure for photocatalytic hydrogen production

Abstract

Owing to the high surface energy of nano-sized materials, the controllable synthesis of ultrafine and uniform cuprous oxide (Cu₂O) nanocrystals (NCs), which show intrinsic advantages in photochemical conversion, still remains a challenge. Herein, by subtly optimizing reaction conditions and designing organic monomers, we successfully synthesize uniformly-sized and well-dispersed Cu₂O NCs (ca. 2.7 nm) on a nanoporous triazole polymer to construct an inorganic/organic heterostructure in a one-pot “click” reaction for the first time. The support of the underlying polymer layer can not only suppress the aggregation and ripening of Cu₂O NCs but also enable their good stability in air, which is confirmed by the well-maintained XRD pattern after 1.5 months. Mechanistic studies reveal that the formation of type-II band alignment between Cu₂O NCs and the triazole polymer promotes charge separation and migration in the inorganic/organic heterostructure, thus improving the activity of visible-light-driven H₂ production in the absence of external cocatalysts. This work provides guidance for the facile synthesis of well-defined heterostructures towards facilitated photochemical conversion.