Ke Yan, Chen Bin, Hu Mengen, Zhou Ningning, Huang Zhulin, Meng Guowen
Key Laboratory of Materials Physics and Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, HIPS, Chinese Academy of Sciences, Hefei 230031, China.
University of Science and Technology of China, Hefei 230026, China.
Nanomaterials (Basel). 2022 Mar 31;12(7):1156. doi: 10.3390/nano12071156.
Plasmon-induced photocatalysis on noble metal surfaces has attracted broad attention due to its application in sunlight energy conversion, while the selectivity of plasmonic platforms remains unclear. Herein, we present the controlled plasmon-mediated oxidation of para-aminothiophenol (-ATP) by employing Au@Ag core-shell nanostars with tunable tip plasmons in visible-near-infrared range as reactors. In-situ Raman measurements indicate that Au@Ag core-shell nanostars essentially promote the conversion of -ATP to 4,4'-dimercaptoazobenzene (DMAB) due to hot carriers excited by localized surface plasmon resonance. Au@Ag nanostars with plasmon modes under resonant light excitation suggested higher catalytic efficiency, as evidenced by the larger intensity ratios between 1440 cm (N=N stretching of DMAB) and 1080 cm shifts (C-S stretching of -ATP). Importantly, the time-dependent surface-enhanced Raman scattering spectra showed that the conversion efficiency of -ATP was mainly dictated by the resonance condition between the tip plasmon mode of Au@Ag core-shell nanostars and the excitation light, as well as the choice of excitation wavelength. These results show that plasmon bands of metal nanostructures play an important role in the efficiency of plasmon-driven photocatalysis.
由于在太阳能转换中的应用，贵金属表面的等离子体激元诱导光催化已引起广泛关注，而等离子体平台的选择性仍不明确。在此，我们以在可见-近红外范围内具有可调尖端等离子体激元的金@银核壳纳米星作为反应器，展示了对4-氨基硫酚（-ATP）的可控等离子体介导氧化。原位拉曼测量表明，由于局域表面等离子体共振激发的热载流子，金@银核壳纳米星本质上促进了-ATP向4,4'-二巯基偶氮苯（DMAB）的转化。在共振光激发下具有等离子体模式的金@银纳米星显示出更高的催化效率，1440 cm（DMAB的N=N伸缩）与1080 cm位移（-ATP的C-S伸缩）之间更大的强度比证明了这一点。重要的是，随时间变化的表面增强拉曼散射光谱表明，-ATP的转化效率主要由金@银核壳纳米星的尖端等离子体激元模式与激发光之间的共振条件以及激发波长的选择决定。这些结果表明，金属纳米结构的等离子体带在等离子体驱动光催化的效率中起着重要作用。
