Nanostructured Dielectric Fractals on Resonant Plasmonic Metasurfaces for Selective and Sensitive Optical Sensing of Volatile Compounds
Journal article, 2018

Advances in the understanding and fabrication of plasmonic nanostructures have led to a plethora of unprecedented optoelectronic and optochemical applications. Plasmon resonance has found widespread use in efficient optical transducers of refractive index changes in liquids. However, it has proven challenging to translate these achievements to the selective detection of gases, which typically adsorb non-specifically and induce refractive index changes below the detection limit. Here, it's shown that integration of tailored fractals of dielectric TiO2nanoparticles on a plasmonic metasurface strongly enhances the interaction between the plasmonic field and volatile organic molecules and provides a means for their selective detection. Notably, this superior optical response is due to the enhancement of the interaction between the dielectric fractals and the plasmonic metasurface for thickness of up to 1.8 μm, much higher than the evanescent plasmonic near-field (≈30 nm). Optimal dielectric–plasmonic structures allow measurements of changes in the refractive index of the gas mixture down to <8 × 10−6at room temperature and selective identification of three exemplary volatile organic compounds. These findings provide a basis for the development of a novel family of dielectric–plasmonic materials with application extending from light harvesting and photocatalysts to contactless sensors for noninvasive medical diagnostics.

Author

Zelio Fusco

Australian National University

Mohsen Rahmani

Australian National University

Renheng Bo

Australian National University

Ruggero Verre

Chalmers, Physics, Bionanophotonics

Nunzio Motta

Queensland University of Technology (QUT)

Mikael Käll

Chalmers, Physics, Bionanophotonics

Dragomir Neshev

Australian National University

Antonio Tricoli

Australian National University

Advanced Materials

09359648 (ISSN) 15214095 (eISSN)

Vol. 30 30 1800931

Subject Categories

Analytical Chemistry

Atom and Molecular Physics and Optics

Other Physics Topics

DOI

10.1002/adma.201800931

More information

Latest update

8/15/2018