Milekhin Alexander G, Yeryukov Nikolay A, Sveshnikova Larisa L, Duda Tatyana A, Rodyakina Ekaterina E, Gridchin Victor A, Sheremet Evgeniya S, Zahn Dietrich R T
A. V. Rzhanov Institute of Semiconductor Physics, pr. Lavrentieva, 13, Novosibirsk 630090, Russia ; Novosibirsk State University, Pirogov str. 2, Novosibirsk 630090, Russia.
A. V. Rzhanov Institute of Semiconductor Physics, pr. Lavrentieva, 13, Novosibirsk 630090, Russia.
Beilstein J Nanotechnol. 2015 Mar 17;6:749-54. doi: 10.3762/bjnano.6.77. eCollection 2015.
We present the results of a Raman study of optical phonons in CuS nanocrystals (NCs) with a low areal density fabricated through the Langmuir-Blodgett technology on nanopatterned Au nanocluster arrays using a combination of surface- and interference-enhanced Raman scattering (SERS and IERS, respectively). Micro-Raman spectra of one monolayer of CuS NCs deposited on a bare Si substrate reveal only features corresponding to crystalline Si. However, a new relatively strong peak occurs in the Raman spectrum of CuS NCs on Au nanocluster arrays at 474 cm(-1). This feature is related to the optical phonon mode in CuS NCs and manifests the SERS effect. For CuS NCs deposited on a SiO2 layer this phonon mode is also observed due to the IERS effect. Its intensity changes periodically with increasing SiO2 layer thickness for different laser excitation lines and is enhanced by a factor of about 30. CuS NCs formed on Au nanocluster arrays fabricated on IERS substrates combine the advantages of SERS and IERS and demonstrate stronger SERS enhancement allowing for the observation of Raman signals from CuS NCs with an ultra-low areal density.
我们展示了一项关于硫化铜纳米晶体（NCs）中光学声子的拉曼研究结果。这些硫化铜纳米晶体具有低密度的面密度，是通过朗缪尔 - 布洛杰特技术在纳米图案化的金纳米团簇阵列上制备而成的，分别结合了表面增强拉曼散射（SERS）和干涉增强拉曼散射（IERS）。沉积在裸硅衬底上的单层硫化铜纳米晶体的显微拉曼光谱仅显示出与晶体硅对应的特征。然而，在金纳米团簇阵列上的硫化铜纳米晶体的拉曼光谱中，在474 cm⁻¹处出现了一个新的相对较强的峰。这一特征与硫化铜纳米晶体中的光学声子模式有关，并体现了SERS效应。对于沉积在二氧化硅层上的硫化铜纳米晶体，由于IERS效应也观察到了这种声子模式。对于不同的激光激发线，其强度随着二氧化硅层厚度的增加而周期性变化，并增强了约30倍。在IERS衬底上制备的金纳米团簇阵列上形成的硫化铜纳米晶体结合了SERS和IERS的优点，并展示出更强的SERS增强效果，从而能够观察到具有超低面密度的硫化铜纳米晶体的拉曼信号。
