A new approach to organic solvent detection: High-reflectivity Bragg reflectors based on a gold nanoparticle/teflon-like composite material

A new sensing element for organic solvents based on a polymeric distributed Bragg reflector (DBR) is presented. The periodic stack consists of alternating Teflon-like and gold nanoparticle/Teflon-like layers, and shows high reflectivity in the optical telecommunications spectral range. Sensing properties are due to the peculiar absorbing behavior of composite layers, which swell in the presence of organic vapors, causing DBR periodicity change and consequently the high reflectivity window shift (see Figure).