Controlled Growth of Sulfide on Gold Nanotriangles with Tunable Local Field Distribution and Enhanced Photocatalytic Activity

Abstract

Metal−semiconductor heteronanostructures have attracted increasing attention due to the strong interactions between the two nanoscale-spaced components. Herein, a steerable hydrothermal method is used to control the growth of Ag 2 S shells onto Au nanotriangles with tunable plasmon resonance and local field distribution. Through adjusting pH value and sulfur source, three types of Au/ Ag 2 S heteronanostructures are obtained, including shells on the tips (Au/Ag 2 S (tips)), shells on the sides (Au/Ag 2 S (sides)), and complete shells (Au@Ag 2 S). The surface plasmon resonance and local field confinement are demonstrated to vary with the shell position. Furthermore, compact CdS nanoshells are coated onto the Au@Ag 2 S without any shape change of Au cores. By testing the photodegradation rate of Rhodamine B (RhB) under visible-light irradiation, the Au@ Ag 2 S@CdS hybrids exhibit enhanced photocatalytic activity compared with Au@CdS and CdS. The strong local electric field, the enhanced visible-light absorption, and the optimum band arrangement between Ag 2 S and CdS are thought to be the main factors.

Pd-Coated Au Triangular Nanoprisms as Catalysts for Hot-Carrier-Driven Photochemistry

“…The observed blue shift of AuTP-Pd compared to the pristine AuTP is due to the negative dielectric constant of Pd in the UV−Vis region and the fact that Pd deposition happens symmetrically from all sides. Such a blue shift of AuNT LSPR due to deposition of Ag was also observed by Ma et al 38 This blue shift and broadening of AuTP plasmon indicated the formation of core−shell nanostructures which were further confirmed from the high-resolution TEM images (Figure 2b−e). It may be also noted that the UV−Vis spectrum of the Pd nanoparticles with an average size of 51 ± 5 nm (Figure S8) showed a broad plasmonic response in the 400−900 nm wavelength range that closely resembles AuTP-8 nm.…”

Controlled growth of plasmonic heterostructures and their applications

“…3d) and nanorods (Fig. 3e, f) [127][128][129]. Very recently, few-layer 2D semiconductors, such as MoS 2 and ReS 2 , have also successfully been overgrown on Au nanoparticles, and very efficient charge transfer has been observed in this type of coreshell nanoparticle [119][120][121].…”

Capability of Au nano-rhombic dodecahedra in a label-free colorimetric assay: application in the determination of S2− and Hg2+

“…For the synthesis of Ag-coated AuNRDs, a previously reported protocol was referred with slight modifications. 27 Briefly, 1 mL of 0.2 M CTAC aqueous solution was added to 4 mL of colloidal AuNRDs. The mixed solution was preheated to 60 °C and kept for 10 min.…”