High-performance dual cavity-interferometric volatile gas sensor utilizing Graphene/PMMA nanocomposite

Volatile organic compounds (VOCs) monitoring is a vital need for many industrial and environmental air quality monitoring applications. We proposed and demonstrated a dual-cavity Fabry-Perot interferometric (DFPI) sensors fabricated by using a polarization maintaining fiber (PMF) immobilized with graphene, PMMA and graphene/PMMA composite for detection of various volatile gases. The optical properties of these materials changes when exposed to different VOCs, which proportionally leads to wavelength and power shift in an interference spectrum due to effective change in refractive index of graphene and swelling of PMMA, respectively. The experimental results are best fitted with models based on Langmuir adsorption isotherm and Hansen solubility parameters. This study focuses on insight into the physical/chemical interaction of volatile gases with versatile sensing materials along with new optical fiber configuration approach, which could be explored for remote detection and air quality monitoring.