The properties of a surface have crucial roles in deter- mining its adhesion, friction, wear and wetting behav- iour, as well as surface chemical processes such as catalysis, corrosion, sintering, composite formation and electrochemistry 1,2 . With the development of surface engineering techniques and nanotechnology, research has shifted from homogeneous to composite materials, from almost perfect single-crystal surfaces to surfaces with functionalized ‘active sites’, and from thin-film materials to promising 2D materials with one to several atomic layers in thickness. Meanwhile, characterization techniques have been developed to reveal the struc- ture–property relationships of these emerging materials. However, for most techniques, the signals obtained from the surfaces are either too weak to detect or are difficult to resolve into distinct components because of the low spectral and spatial resolution. Therefore, it is necessary to develop in situ techniques with ultrahigh sensitivity, surface specificity, high spectral resolution, and high spatial and temporal resolution. One such technique is surface-enhanced Raman spectroscopy (SERS) 3–5 , which can realize an ultrahigh sensitivity down to the single-molecule level by means of coinage-metal (for example, Au, Ag and Cu) nano- structures 6,7 . The SERS effect is due to the amplification of Raman signals of analytes by several orders of magni- tude when the analytes are located at or very close to coinage-metal nanostructures (the working princi- ples of SERS are described in BOXES 1,2) 8 . The SERS enhancement of these nanostructures strongly relies on the optical resonance properties of coinage-metal nanostructures, which can significantly enhance the local electromagnetic field, largely owing to the excita- tion of surface plasmon resonance (SPR) 9,10 . Based on similar surface-enhancement mechanisms, many other surface-enhanced Raman methods, including the two important variants of SERS — tip-enhanced Raman spectroscopy (TERS) 11–14 and shell-isolated nanoparticle- enhanced Raman spectroscopy (SHINERS) 15 — as well as ultraviolet SERS, near-infrared SERS 16–18 and surface-enhanced nonlinear Raman spectroscopy 19–22 , have been developed for a wide range of applications. The above-mentioned techniques can be collectively described as plasmon-enhanced Raman spectroscopy (PERS) 23 (a timeline of the key developments of PERS techniques is provided in FIG. 1). PERS enhancement is strongly dependent on the opti- cal properties, shape and aggregation of nanomaterials 24 . In the 1970s and 1980s, SERS-active substrates, such as roughened Au and Ag electrodes, colloidal aggregates 1 State Key Laboratory for Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, iChEM, Xiamen University. 2 MOE Key Laboratory of Spectrochemical Analysis and Instrumentation, Xiamen University, Xiamen 361005, China. Correspondence to Z-.Q.T.  zqtian@xmu.edu.cn Article number: 16021 doi:10.1038/natrevmats.2016.21 Published online 26 Apr 2016 Nanostructure-based plasmon- enhanced Raman spectroscopy for surface analysis of materials Song-Yuan Ding 1 , Jun Yi 1 , Jian-Feng Li 1,2 , Bin Ren 1,2 , De-Yin Wu 1 , Rajapandiyan Panneerselvam 1 and Zhong-Qun Tian 1 Abstract | Since 2000, there has been an explosion of activity in the field of plasmon-enhanced Raman spectroscopy (PERS), including surface-enhanced Raman spectroscopy (SERS), tip-enhanced Raman spectroscopy (TERS) and shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS). In this Review, we explore the mechanism of PERS and discuss PERS hotspots — nanoscale regions with a strongly enhanced local electromagnetic field — that allow trace-molecule detection, biomolecule analysis and surface characterization of various materials. In particular, we discuss a new generation of hotspots that are generated from hybrid structures combining PERS-active nanostructures and probe materials, which feature a strong local electromagnetic field on the surface of the probe material. Enhancement of surface Raman signals up to five orders of magnitude can be obtained from materials that are weakly SERS active or SERS inactive. We provide a detailed overview of future research directions in the field of PERS, focusing on new PERS-active nanomaterials and nanostructures and the broad application prospect for materials science and technology. NATURE REVIEWS | MATERIALS ADVANCE ONLINE PUBLICATION | 1 REVIEWS ©2016MacmillanPublishersLimited.Allrightsreserved.