Microfabricated Formaldehyde Gas Sensors

Abstract

Formaldehyde is a volatile organic compound that is widely used in textiles, paper, wood composites, and household materials. Formaldehyde will continuously outgas from manufactured wood products such as furniture, with adverse health effects resulting from prolonged low-level exposure. New, microfabricated sensors for formaldehyde have been developed to meet the need for portable, low-power gas detection. This paper reviews recent work including silicon microhotplates for metal oxide-based detection, enzyme-based electrochemical sensors, and nanowire-based sensors. This paper also investigates the promise of polymer-based sensors for low-temperature, low-power operation.

SnO

“…From such a curve, film resistance can be calibrated for a given operating temperature for implementation as a sensor device, having a one-to-one relationship between resistance changes and HCHO concentrations. 1 Films deposited at substrate temperatures below 250…”

“…Many types of commercial HCHO sensors are available, but few can quantitatively detect HCHO at concentrations below 100 ppb [1]. A recent Health Canada guideline [2] sets the maximum HCHO concentration for short-term (1-hour averaged) and long-term (8-hour averaged) exposure limits at 100 ppb and 40 ppb, respectively.…”

Nanocomposite sensors of propylene glycol, dimethylformamide and formaldehyde vapors

“…There are only studies on sensors working on other principles (for example, sensors working on a modification of the color of the substance), which is incompatible with modern techniques, while resistive gas sensors, made from metal oxides, have some advantages such as availability of the electric signal, measurement of gas concentration, small sizes, low power consumption, high sensitivity and high reliability (Fine et al, 2010;Korotcenkov et al, 2013). As opposed to this case, there are various types of FA gas sensors: for instance, FA gas sensors based on graphene or polymers, which are working at a room temperature (Chuang et al, 2015;Flueckiger et al, 2009). However, FA gas sensors, which are based on metal-oxide materials, have benefits that are mentioned above.…”

A Novel Odor Key Technique for Security Applications Using Electronic Nose System

“…Using the feature set instead of the original signal allows for fast and compact data analysis. The obtained data is modeled using a simple physical description of the measurement system based on the following assumptions (Rodriguez et al, 2010;RagazzoSancheza et al, 2009;Brudzewski and Ulaczyk, 2009;Men et al, 2010;Romain and Nicolas, 2010;Bahraminejad et al, 2010;Flueckiger et al, 2009;Baha and Dibi, 2009):…”