A whispering-gallery mode (WGM) optical resonance sensor for volatile organic compounds (VOCs) is developed from polystyrene (PS) microspheres doped with fluorescent βcyano-appended oligo(p-phenylenevinylene) (β-COPV). The β-COPV-doped PS microspheres (MS COPV ) are formed by the miniemulsion method in a binary solvent. MS COPV expand upon permeation of VOCs into the PS matrix and exhibit a spectral shift of the WGM resonance peak. The permeation efficiency is highly dependent on the chemical affinity between the analyte and the polymer matrix, with exceptionally high selectivity toward aromatic hydrocarbons such as benzene, toluene, and xylenes (BTXs). The high selectivity and sensitivity of MS COPV are in clear contrast to those of conventional WGM sensors that just detect VOCs nonpreferentially through adsorption onto the surface.

Self-assembled microspherical aggregates that work as whispering gallery mode (WGM) optical resonators are synthesized from a novel hygroscopic polymer covalently appended with an aggregation-induced emission luminogen. The resultant microspheres can...

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Fluorinated surfaces show favorable physical properties for material applications. However, fluorination processes of bulk surfaces using conventional reagents require skilled techniques and special equipment. Herein, we demonstrate highly efficient surface modification using a new fluorination tool, perfluoroalkyl‐substituted stable nitrile N‐oxide. The nitrile N‐oxide is successfully synthesized in one‐pot by exploiting 1,1‐diphenylnitroethene as the precursor of nitrile N‐oxide. The nitrile N‐oxide exhibits not only high reactivity but also thermal stability, which enables the simple chemical modification of allyl group‐modified rigid surfaces without catalysts or byproducts. The surface is analysed by X‐ray photoelectron spectroscopy, time‐of‐flight secondary ion mass spectrometry, and contact angle measurements, providing clear evidence that the perfluoroalkyl groups are densely integrated on the bulk surface as a result of the efficient covalent bond formation.