A Review: Application and Implementation of Optic Fibre Sensors for Gas Detection

Abstract

At the present time, there are major concerns regarding global warming and the possible catastrophic influence of greenhouse gases on climate change has spurred the research community to investigate and develop new gas-sensing methods and devices for remote and continuous sensing. Furthermore, there are a myriad of workplaces, such as petrochemical and pharmacological industries, where reliable remote gas tests are needed so that operatives have a safe working environment. The authors have concentrated their efforts on optical fibre sensing of gases, as we became aware of their increasing range of applications. Optical fibre gas sensors are capable of remote sensing, working in various environments, and have the potential to outperform conventional metal oxide semiconductor (MOS) gas sensors. Researchers are studying a number of configurations and mechanisms to detect specific gases and ways to enhance their performances. Evidence is growing that optical fibre gas sensors are superior in a number of ways, and are likely to replace MOS gas sensors in some application areas. All sensors use a transducer to produce chemical selectivity by means of an overlay coating material that yields a binding reaction. A number of different structural designs have been, and are, under investigation. Examples include tilted Bragg gratings and long period gratings embedded in optical fibres, as well as surface plasmon resonance and intra-cavity absorption. The authors believe that a review of optical fibre gas sensing is now timely and appropriate, as it will assist current researchers and encourage research into new photonic methods and techniques.

Significance of Various Sensing Mechanisms for Detecting Local and Atmospheric Greenhouse Gases: A Review

“…Highlighted in the sections above, a vast array of traditional, novel, and hybrid complex materials have been uncovered and adopted within the frameworks of sensors dedicated toward detecting GHGs. These include the carbon nanomaterials, polymers, metal oxide semiconductors, and transition metal dichalcogenides, in calorimetric sensors; [102,108,117,122]] the solid polymer electrolytes, pseudo-solid-state electrolytes, and carbon materials, in electrochemical sensors; [67][68][69]109,121,133,137]] pyroelectric elements, LEDs, and PDs, in IR/FTIR/NDIR sensors; [72][73][74][75][76]78,84,85,109,131]] metal oxides, carbon materials, polymers, and single-or multi-mode optical fibers, in opticalbased sensors; [86][87][88][89][90][92][93][94]109,134]] piezoelectric materials, piezoceramics, carbon materials, and polymers, in acoustic/ultrasonic sensors; [91,[95][96][97][98][99]100,110,111] as well as polymer films in calorimetric or gas chromatographic sensors. [103,104,…”

Optical Fiber‐Based Gas Sensing for Early Warning of Thermal Runaway in Lithium‐Ion Batteries

“…Thus, part of the light transfers from core mode into cladding modes, and even escapes from the fiber in a radiative mode. [47] The cladding modes propagate backward and interfere with forward core modes, resulting in a series of peak drops in the transmission spectrum. The interference wavelengths can be written as: where n eff,core and n i eff ,clad are the effective RI of core mode and ith cladding mode, respectively.…”

“…Thus, part of the light transfers from core mode into cladding modes, and even escapes from the fiber in a radiative mode. [ 47 ] The cladding modes propagate backward and interfere with forward core modes, resulting in a series of peak drops in the transmission spectrum. The interference wavelengths can be written as: $$$$\begin{equation}{\lambda }_{\mathrm{B}} = \left( {{n}_{{\mathrm{eff}},{\mathrm{core}}} + {n}^i_{{\mathrm{eff}},{\mathrm{clad}}}} \right)\Lambda /\cos \theta \end{equation}$$$$where n eff,core and $${n}^i_{{\mathrm{eff}},{\mathrm{clad}}}$$ are the effective RI of core mode and i th cladding mode, respectively.…”

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).…”