Liquid interfacial plasmonic platform is emerging for new sensors, catalysis, and tunable optical devices, but also promises an alternative for practical applications of surface-enhanced Raman spectroscopy (SERS). Here we show that vigorous mixing of chloroform with citrate-capped gold nanorod sols triggers the rapid self-assembly of three-dimensional plasmonic arrays at the chloroform/water (O/W) interface and produces a self-healing metal liquid-like brilliant golden droplet. The O phase itself generates stable SERS fingerprints and is a good homogeneous internal standard for quantitative analysis. This platform presents reversible O/W encasing in a common cuvette determined just by surface wettability of the container. Both O-in-W and W-in-O platforms exhibit excellent SERS sensitivity and reproducibility for different analytes by the use of a portable Raman device. It paves the way toward a practical and quantitative liquid-state SERS analyzer, likened to a simple UV–Vis spectrometer, that is far superior to typical solid substrate-based or nanoparticle sol-based analysis.

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Graphene and MoS 2 were dispersed in Esterified Bio-Oil (EBO) and evaluated as lubricants for steel/steel contact. The tribological behaviors of steel/steel pairs were investigated under lubrication of graphene/MoS 2 blends with different mass ratios, loads and rotating speeds.The micro-morphologies of the worn surfaces were observed by optical and Scanning Electron Microscopy (SEM). The components of the additives and chemical valences of the elements on the rubbed surfaces were analyzed using Raman and X-ray Photoelectron Spectroscopy (XPS). A synergistic lubricating effect for both graphene and MoS 2 with contents of 0.5 wt.% as additives dispersed in EBO was observed that reduced the friction coefficient and wear of the steel specimens under boundary lubrication regime conditions. This was ascribed to the formation of a thicker adsorbed tribo film containing graphene, MoS 2 and organics from the EBO. Graphene was shown to improve the retention of MoS 2 on the frictional surfaces and prevent oxidation during rubbing.MoS 2 , on the other hand, prevented the graphene from being ground into small and defective platelets. Corresponding author. Tel/

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