Super-heterostructures of twisted Pd nanoarrays epitaxially grown on chiral Au nanorods boost circularly polarized photocatalysis

Abstract

Seed-mediated growth provides an efficient way to produce chiral hybrid nanocrystals, mainly benefitting from the recent successful synthesis of discrete chiral metal nanocrystals. However, the chiroptical response of chiral core-shell nanostructures decreases rapidly when the functional layer is grown on the discrete chiral metal nanocrystals. Herein, a synthetic methodology is demonstrated for the formation of chiral Au@Pd super-heterostructures, in which Pd nanoarrays are epitaxially and densely grown with a twisted lattice on discrete chiral Au nanorods (Pd-on-cAuNRs). The highly aligned Pd nanoarrays on cAuNRs exhibit good chiroptical performance. Importantly, the Pd-on-cAuNR super-heterostructures display chiral behavior in their catalytic actions, with the catalytic performance of D-super-heterostructures being twice higher than that of its L- super-heterostructures. In addition, under circularly polarized light (CPL) irradiation, the chiral electromagnetic field and hot electrons generated on the chiral super-heterostructures boost circularly polarized photocatalytic activity, the mechanism of which is supported by theoretical simulations and chiral photocurrent experiments. This research work offers fundamental insights on chiral surface plasmon resonance-induced photocatalysis and rational design of chiral nanostructure photocatalysts. Graphical abstract: [Figure not available: see fulltext.]