High Sensitivity All-Fibre Methane Sensor with Gas Permeable Teflon/Cryptophane-A Membrane

Abstract

We demonstrate a simple, cheap and compact all fibre methane sensor, with record sensitivity of 0.16 nm/ppm, composed of a D-shaped cross section optical fibre in between two fibre Bragg gratings. The flat side of the fibre is coated with a unique membrane used to solely detect methane, made by a gas permeable Teflon layer and doped with cryptophane-A molecules.