Application of ordered nanoparticle self-assemblies in surface-enhanced spectroscopy

Surface-enhanced spectroscopy (SES), including surface-enhanced Raman spectroscopy (SERS), surface-enhanced infrared absorption (SEIRA), surface-enhanced fluorescence (SEF), surface-enhanced hyper-Raman spectroscopy (SEHRS), surface-enhanced second harmonic generation (SESHG), and surface-enhanced electrochemiluminescence (SEECL), is an emerging subject that has received significant attention from the research community over the past 40 years. The confined and strong enhanced electromagnetic fields generated from the surface of noble metal nanostructures are considered as the main cause of SES. More importantly, it has been proven that SES is strongly related to the orientation and inter-nanoparticle coupling of different nanostructures. This review article mainly focuses on the application of ordered nanoparticle self-assemblies in SES. Different strategies for the fabrication of ordered nanoparticle self-assemblies, the mechanisms of SES, and the application of SES have been reviewed in detail.