Review on recent developments of fluorescent oxygen and carbon dioxide optical fiber sensors

Abstract

Oxygen and carbon dioxide sensors are involved in many chemical and biochemical reactions. Consequently, considerable efforts over years have been devoted to discover and improve suitable techniques for measuring gas concentrations by optical fiber sensors. Optical gas sensors consist of a gas-sensitive dye entrapped in a matrix with a high permeability to gas. With such sensors, gas concentration is evaluated based upon the reduction in luminescence intensity caused by gas quenching of the emitting state. However, the luminescence quenching effect of oxygen is highly sensitive to temperature. Thus, a simple, low-cost plastic optical fiber sensor for dual sensing of temperature and oxygen is presented. Also, a modified Stern-Volmer model is introduced to compensate for the temperature drift while the temperature is obtained by above dual sensor. Recently, we presented highly-sensitive oxygen and dissolved oxygen sensors comprising an optical fiber coated at one end with platinum (II) meso-tetrakis(pentafluorophenyl)porphyrin (PtTFPP) and PtTFPP entrapped core-shell silica nanoparticles embedded in an n-octyltriethoxysilane(Octyl-triEOS)/tetraethylorthosilane (TEOS) composite xerogel. Also, two-dimensional gas measurement for the distribution of chemical parameters in non-homogeneous samples is developed and is of interest in medical and biological researches.

Fiber Optic Sensors Based on Nanostructured Materials

“…This kind of chemical dyes can be also used to prepare sensors for gas detection such as ammonia [82]. Another relevant application is oxygen detection, in which metallic salts are employed (ruthenium and platinum ones mainly) [83].…”

“…13.7a). On the contrary, if the resulting matrix is nonpolar, the porous size can be designed to discriminate between VOCs and their polarity [82]. Figure 13.8 shows the comparative response of reflection sensors with no deposition (bare fiber), with a xerogel membrane and one doped with a material sensitive to organic vapors: although the non-doped membrane is also sensitive to organic vapors, it is clear that the response is better in the last case.…”

Nanostructured Materials in Optical Fiber Sensing

“…Thus, the sensitivity of the optical sensor depends on both the fluorescence intensity of the dye and the matrix characteristics, such as its density, viscosity, hydrophobicity, transparency etc. [45].…”

“…Fluorescent molecules have been traditionally used in the fabrication of optical fiber sensors [45]. These molecules can be easily entrapped into a supporting matrix and adhered to the optical fiber using different fabrication techniques and optical fiber configurations as it is summarised in ( Table 1).…”

A Gas Sensor Device for Oxygen and Carbon Dioxide Detection

“…Different application fields require different concentration ranges, but on-field and on-line applicability is of course mandatory. The state of the art is represented by electrochemical, optical and conductometric approaches [3][4][5][6], with excellent pros and not negligible cons.…”