Ag‐CdS Yolk–Shell Heteronanostructures for Plasmon‐Enhanced Photocatalysis

Abstract

The combination of a semiconductor and a plasmonic metal holds great promise for developing advanced photocatalysts. However, the realization of a heteronanostructure that accommodates both materials in an effective way has been a great challenge. Herein, we report a synthesis of a photocatalyst with a yolkshell heteronanostructure, which contains a plasmonic Ag yolk inside a CdS shell. The sulfidation of Ag nanospheres followed by a controlled cation exchange reaction successfully generated the Ag-CdS yolkshell nanostructures. The as-prepared heteronanostructures exhibited a prominent enhancement of photocatalytic activity toward hydrogen evolution reaction under visible-light irradiation compared to CdS hollow nanoparticles without the Ag yolk. This improvement can be attributed to the plasmon energy transfer from the Ag yolk to the CdS shell and the yolk-shell structure that enables the multiple reflections of the incident light.

Optimized hot electron injection from Cu nanoparticles to S-doped C3N4by the formed S–Cu bonds for an enhanced photocatalytic performance

“…Cu NPs can improve the photocatalytic performance of CN and SCN through different mechanisms, such as enhanced near-field absorption 2 or far-field scattering, 3 plasmon-induced resonance energy transfer process 4 or hot electron injection during the SPR decoherence, 5 so the specific enhancement mechanism of Cu NPs needs to be estimated. Considering there is no spectral overlap between Cu NPs with CN or SCN (Fig.…”

“…Furthermore, 0.001 M of MVCl 2 was added as an electronic intermediary to the electrolyte and the transient photocurrent of CN-0.35Cu and SCN-0.3Cu was tested to study the effect of Cu-S bonds on the surface charge transfer efficiency (Z t ), as shown in Fig. S12 (ESI †), and Z t could be calculated by eqn (5): 35 Z t = J P /J m P (5) where J p is the detected photocurrent intensity, and J m p is the theoretical maximum photocurrent intensity after 0.001 M of MVCl 2 . After adding MVCl 2 , the photocurrent of CN-0.35Cu increased from 460.43 to 920.86 nA cm À2 and that of SCN-0.3Cu increased from 2302.14 to 3069.52 nA cm À2 , and the corresponding Z t can be calculated as 20.0% and 30.0%, respectively.…”

“…1 SPR nanostructures can enhance the photoelectric conversion process of semiconductors via different mechanisms, such as enhanced near-field absorption 2 or far-field scattering, 3 plasmon-induced resonance energy transfer process 4 or hot carrier injection during the SPR decoherence. 5 As a typical example, the enhanced photocatalytic performance can be realized by the introduction of SPR nanostructures. Au and Ag nanostructures are the most popular SPR materials, but their high price inhibits their large-scale practical application.…”

Galvanic replacement reaction to prepare catalytic materials

“…Metal sulfides have been found compatible with post‐synthetic techniques such as cation exchange reactions. Several notable examples have been reported on the successful diversification of cation compositions in sulfide NPs by cation exchange reactions 92–94 . The ion exchange reactions have demonstrated the ability to control the compositional and morphological complexity in NPs, providing a great opportunity for vast structural diversity of nanostructures 95–98 .…”

“…Several notable examples have been reported on the successful diversification of cation compositions in sulfide NPs by cation exchange reactions. [92][93][94] The ion exchange reactions have demonstrated the ability to control the compositional and morphological complexity in NPs, providing a great opportunity for vast structural diversity of nanostructures. [95][96][97][98] The metastable nature of the material phases and the high cation mobility allow the introduction of various elements to form semiconductorsemiconductor interfaces, which might find useful applications in catalysis.…”