Synthesis of Dumbbell‐Like Gold–Metal Sulfide Core–Shell Nanorods with Largely Enhanced Transverse Plasmon Resonance in Visible Region and Efficiently Improved Photocatalytic Activity

Abstract

The metallic nanostructures with unique properties of tunable plasmon resonance and large field enhancement have been cooperated with semiconductor to construct hetero‐nanostructures for various applications. Herein, a general and facile approach to synthesize uniform dumbbell‐like gold–sulfide core–shell hetero‐nanostructures is reported. The transformation from Au nanorods (NRs) to dumbbell‐like Au NRs and coating of metal sulfide shells (including Bi2S3, CdS, CuxS, and ZnS) are achieved in a one‐pot reaction. Due to the reshaping of Au core and the deposition of sulfide shell, the plasmon resonances of Au NRs are highly enhanced, especially the about 2 times enhancement for the visible transverse plasmon resonance compared with the initial Au NRs. Owing to the highly enhanced visible light absorption and strong local electric field, we find the photocatalytic activity of dumbbell‐like Au–Bi2S3 NRs is largely enhanced compared with pure Bi2S3 and normal Au–Bi2S3 NRs by testing the photodegradation rate of Rhodamine B (RhB). Moreover, the second‐layer sulfide can be coated and the double‐shell Au–Bi2S3–CdS hetero‐nanostructures show further improved photodegradation rate, especially about 2 times than that of Degussa P25 TiO2 (P25) ascribing to the optimum band arrangement and then the prolonged lifetime of photo‐generated carriers.

UV and visible light photocatalytic activity of Au/TiO2 nanoforests with Anatase/Rutile phase junctions and controlled Au locations

“…For TiO 2 decorated with Au and Ag, there is an additional effect, the localized surface plasmon resonance (LSPR), which contributes to a strong absorption of the visible light and thus the photocatalytic performance under the visible light illumination131415. The LSPR effect is affected readily by shape16, size171819, and content20 of Au nanoparticles, as well as characteristics of the TiO 2 supports13182122.…”

Understanding of the major reactions in solution synthesis of functional nanomaterials

“…Another method to grow metal sulfide is by means of seed growth. Recently, Ma and co-workers [137] reported a general and facile method to prepare homogeneous dumbbell-like gold-sulfide core-shell hetero-nanostructures. The evolution from Au nanorods to dumbbell-like Au nanorods and the coating of metal sulfide shells were achieved in a one-pot reaction (Fig.…”

Size/Shape Controlled Synthesis of Au/Tio2 Nano-Composites

“…But such a size-controlled synthesis is a current challenge in the field of nano-catalysis. The LSPR properties are influenced by the shape [5], size [6][7][8] and gold loading [9]. Several approaches have been applied to control the size/shape of gold nanoparticles supported on titania including loading change [10][11], sol-immobiliztion [12][13][14], pore confinement [15] self assembly [16].…”