Optical Fiber Sensors Based on Microstructured Optical Fibers to Detect Gases and Volatile Organic Compounds—A Review

Abstract

Since the first publications related to microstructured optical fibers (MOFs), the development of optical fiber sensors (OFS) based on them has attracted the interest of many research groups because of the market niches that can take advantage of their specific features. Due to their unique structure based on a certain distribution of air holes, MOFs are especially useful for sensing applications: on one hand, the increased coupling of guided modes into the cladding or the holes enhances significantly the interaction with sensing films deposited there; on the other hand, MOF air holes enhance the direct interaction between the light and the analytes that get into in these cavities. Consequently, the sensitivity when detecting liquids, gasses or volatile organic compounds (VOCs) is significantly improved. This paper is focused on the reported sensors that have been developed with MOFs which are applied to detection of gases and VOCs, highlighting the advantages that this type of fiber offers.

Advances in Optical Sensors for Persistent Organic Pollutant Environmental Monitoring

“…The last generation FOCS sensors use the combination of surface plasmon resonance (SPR) sensing platform on plastic optical fibers (POFs), or use photonic crystal fibers (PCF). In addition, micro-structured optical fibers (MOFs), having a certain distribution of air holes in their structure, have been actively used recently for sensing applications for detecting liquids, gases, or volatile organic compounds (VOCs) [ 99 ].…”

A vapochromic dye/graphene coated long-period fiber grating for benzene vapor sensing

“…The optical fiber sensor is based on the refractive index sensing principle, which has the significant advantage of immunity to electromagnetic interference compared to electronic or electrical sensors. [38][39][40] At the same time, real-time and remote sensing can be achieved with the benefit of advanced optical fiber sensing networks. 41 In optical fibers, the different modes of light are orthogonal and do not interfere with each other.…”

Polyacrylic Acid/Polyaniline-Coated Multimode Interferometer for Ammonia Detection

“…Various types of NH 3 sensors have been reported during the last decades [ 5 , 6 , 7 ]. Among them, due to the merits of small size, resistance to electromagnetic interference, and high sensitivity [ 8 ], optical fiber sensors have been widely studied in the field of gas sensing [ 9 , 10 , 11 , 12 ]. For instance, Xu et al [ 13 ] reported a highly sensitive NH 3 sensor by coating graphene oxide (GO)/cellulose acetate (CA) on the surface of a long-period fiber grating (LPFG).…”