Carbon nanofiber flexible gas sensor modulated by UV light

Abstract

Herein, we present a flexible gas sensor based on carbon nanofibers (CNFs). The sensing device was fabricated by means of low-cost techniques: inkjet printing and spray coating. Characterization on the use of ultraviolet (UV) light in order to modulate the sensor signal was performed. Sensor response and characteristics times (response time, τ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">resp</sub> ; and recovery time, τ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rec</sub> ) were fully characterized. UV illumination was also chosen to anneal the sensing active layer in the fabrication process and to fasten desorption of the gas adsorbed, achieving a stable sensor signal. Furthermore, better conditions of UV radiation to optimize τ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">resp</sub> and τ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rec</sub> were found.