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Formaldehyde gas sensors: a review.

Chung PR, Tzeng CT, Ke MT, Lee CY - Sensors (Basel) (2013)

Bottom Line: Accordingly, the emergence of sophisticated technologies in recent years has prompted the development of many microscale gaseous formaldehyde detection systems.Besides their compact size, such devices have many other advantages over their macroscale counterparts, including a real-time response, a more straightforward operation, lower power consumption, and the potential for low-cost batch production.This paper commences by providing a high level overview of the formaldehyde gas sensing field and then describes some of the more significant real-time sensors presented in the literature over the past 10 years or so.

View Article: PubMed Central - PubMed

Affiliation: Department of Architecture, National Cheng Kung University, Tainan 701, Taiwan. benjamin@archilife.ncku.edu.tw

ABSTRACT
Many methods based on spectrophotometric, fluorometric, piezoresistive, amperometric or conductive measurements have been proposed for detecting the concentration of formaldehyde in air. However, conventional formaldehyde measurement systems are bulky and expensive and require the services of highly-trained operators. Accordingly, the emergence of sophisticated technologies in recent years has prompted the development of many microscale gaseous formaldehyde detection systems. Besides their compact size, such devices have many other advantages over their macroscale counterparts, including a real-time response, a more straightforward operation, lower power consumption, and the potential for low-cost batch production. This paper commences by providing a high level overview of the formaldehyde gas sensing field and then describes some of the more significant real-time sensors presented in the literature over the past 10 years or so.

No MeSH data available.


(a) Schematic illustration of formaldehyde sensor in which formaldehyde molecules react with Fluoral-P molecules to form DDL, which is then excited by LED with wavelength of 405 nm; (b) Pulse-mode detection of HCHO in atmosphere with relative humidity of 50% with and without humidity filter, respectively [28].
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f6-sensors-13-04468: (a) Schematic illustration of formaldehyde sensor in which formaldehyde molecules react with Fluoral-P molecules to form DDL, which is then excited by LED with wavelength of 405 nm; (b) Pulse-mode detection of HCHO in atmosphere with relative humidity of 50% with and without humidity filter, respectively [28].

Mentions: Descamps et al. [28] proposed a colorimetric device for measuring the concentration of gaseous formaldehyde incorporating a nanoporous film doped with Fluoral-P. When exposed to gaseous formaldehyde, the HCHO molecules reacted with the Fluoral-P reagent to form 3,5-diacetyl-1,4-dihydrolutidine (DDL). The formaldehyde concentration was then determined by measuring the intensity of the fluorescence emission signal given the use of a LED illumination light source with a wavelength of 405 nm (see Figure 6(a)). In computing the formaldehyde concentration, the DDL concentration was formulated as:(1)[DDL]=a(1−exp(−bt))where a and b include the reaction rate k, the initial concentration of Fluoral-P [F]0, and the formaldehyde concentration [HCHO], i.e.,:(2)a∝[F]0b=k[HCHO][F]0 was assumed to be constant throughout the experiments, and thus a X b was proportional to the formaldehyde concentration (Equation (2)). The experimental results showed a relative scattering of +20% for formaldehyde concentrations lower than 90 ppb and a minimum detection limit of 30 ppb (Figure 6(b)).


Formaldehyde gas sensors: a review.

Chung PR, Tzeng CT, Ke MT, Lee CY - Sensors (Basel) (2013)

(a) Schematic illustration of formaldehyde sensor in which formaldehyde molecules react with Fluoral-P molecules to form DDL, which is then excited by LED with wavelength of 405 nm; (b) Pulse-mode detection of HCHO in atmosphere with relative humidity of 50% with and without humidity filter, respectively [28].
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3673094&req=5

f6-sensors-13-04468: (a) Schematic illustration of formaldehyde sensor in which formaldehyde molecules react with Fluoral-P molecules to form DDL, which is then excited by LED with wavelength of 405 nm; (b) Pulse-mode detection of HCHO in atmosphere with relative humidity of 50% with and without humidity filter, respectively [28].
Mentions: Descamps et al. [28] proposed a colorimetric device for measuring the concentration of gaseous formaldehyde incorporating a nanoporous film doped with Fluoral-P. When exposed to gaseous formaldehyde, the HCHO molecules reacted with the Fluoral-P reagent to form 3,5-diacetyl-1,4-dihydrolutidine (DDL). The formaldehyde concentration was then determined by measuring the intensity of the fluorescence emission signal given the use of a LED illumination light source with a wavelength of 405 nm (see Figure 6(a)). In computing the formaldehyde concentration, the DDL concentration was formulated as:(1)[DDL]=a(1−exp(−bt))where a and b include the reaction rate k, the initial concentration of Fluoral-P [F]0, and the formaldehyde concentration [HCHO], i.e.,:(2)a∝[F]0b=k[HCHO][F]0 was assumed to be constant throughout the experiments, and thus a X b was proportional to the formaldehyde concentration (Equation (2)). The experimental results showed a relative scattering of +20% for formaldehyde concentrations lower than 90 ppb and a minimum detection limit of 30 ppb (Figure 6(b)).

Bottom Line: Accordingly, the emergence of sophisticated technologies in recent years has prompted the development of many microscale gaseous formaldehyde detection systems.Besides their compact size, such devices have many other advantages over their macroscale counterparts, including a real-time response, a more straightforward operation, lower power consumption, and the potential for low-cost batch production.This paper commences by providing a high level overview of the formaldehyde gas sensing field and then describes some of the more significant real-time sensors presented in the literature over the past 10 years or so.

View Article: PubMed Central - PubMed

Affiliation: Department of Architecture, National Cheng Kung University, Tainan 701, Taiwan. benjamin@archilife.ncku.edu.tw

ABSTRACT
Many methods based on spectrophotometric, fluorometric, piezoresistive, amperometric or conductive measurements have been proposed for detecting the concentration of formaldehyde in air. However, conventional formaldehyde measurement systems are bulky and expensive and require the services of highly-trained operators. Accordingly, the emergence of sophisticated technologies in recent years has prompted the development of many microscale gaseous formaldehyde detection systems. Besides their compact size, such devices have many other advantages over their macroscale counterparts, including a real-time response, a more straightforward operation, lower power consumption, and the potential for low-cost batch production. This paper commences by providing a high level overview of the formaldehyde gas sensing field and then describes some of the more significant real-time sensors presented in the literature over the past 10 years or so.

No MeSH data available.