Localized Surface Plasmon Resonance-Enhanced Two-Photon Excited Ultraviolet Emission of Au-Decorated ZnO Nanorod Arrays
Localized Surface Plasmon Resonance-Enhanced Two-Photon Excited Ultraviolet Emission of Au-Decorated ZnO Nanorod Arrays
复制标题
Au修饰的ZnO纳米棒阵列的局域表面等离子体共振增强双光子激发紫外发射
DOI：
10.1002/adom.201300302
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发表时间：
2013-12-01
影响因子：
9
通讯作者：
Wang, Baoping
中科院分区：
文献类型：
--
作者：
Lin, Yi;Xu, Chunxiang;Wang, Baoping
制备了ZnO纳米棒阵列和Au修饰的ZnO纳米棒阵列。根据Au纳米粒子（NPs）的局域表面等离子体共振（LSPR）位置，选择不同的激发波长，研究了这两种样品的双光子激发紫外发射。结果表明，在对应于Au纳米粒子LSPR吸收的激发下，Au修饰ZnO样品的双光子激发阈值远低于未修饰ZnO样品的双光子激发阈值。在相同的激发功率下，将Au纳米粒子组装到ZnO纳米棒表面后，紫外发射强度得到了显著增强。这种改善归因于由Au NP的LSPR产生的强局部场增强。实验表明，共振过程取决于激发波长靠近或远离Au NPs的LSPR峰。这些研究为探讨LSPR增强ZnO紫外发光的机理提供了直接的证据，也为设计具有高发光效率的金属-半导体纳米结构提供了理论依据。
ZnO nanorod arrays and their Au-decorated counterparts are fabricated. The two-photon excited ultraviolet emissions of these two samples are studied by selecting different excitation wavelengths according to the localized surface plamsmon resonance (LSPR) position of Au nanoparticles (NPs). It is found that the two-photon excitation threshold of Au-decorated ZnO sample is much lower than that of the as-grown sample under an excitation corresponding to the LSPR absorption of Au NPs, such as 520 nm. Under the same excitation power, the UV emission intensity is strongly enhanced after the Au NPs are assembled on the surfaces of ZnO nanorods. This improvement is attributed to a strong local field enhancement generated by the LSPR of Au NPs. Experiments demonstrate that the resonant process depends on the excitation wavelength near or far from the LSPR peak of Au NPs. These studies provide direct evidence for the mechanism of LSPR-enhanced UV emission of ZnO, and are helpful to design proper metal-semiconductor nanostructures with high luminescence efficiency.