Silver Enhances Hematite Nanoparticles Based Ethanol Sensor Response and Selectivity at Room Temperature
Daniel Garcia-Osorio,
Pilar Hidalgo-Falla,
Henrique E. M. Peres,
Josue M. Gonçalves,
Koiti Araki,
Sergi Garcia-Segura,
Gino Picasso
Affiliations
Daniel Garcia-Osorio
Laboratory of Physical Chemistry Research, Faculty of Sciences, National University of Engineering, Av. Tupac Amaru 210, 15333 Lima, Peru
Pilar Hidalgo-Falla
Laboratory of Nanotechnology, Faculty of Gama, Area Especial de Indústria Projeção A, UNB—DF-480, University of Brasilia, Gama Leste, 72444-240 Brasilia, Brazil
Henrique E. M. Peres
Department of Electronic System Engineering, EPUSP, University of São Paulo, Av. Prof. Luciano Gualberto, 158, Trav. 3, 05508-900 São Paulo, Brazil
Josue M. Gonçalves
Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, Av. Prof. Lineu Prestes 748, Butanta, 05508-000 São Paulo, Brazil
Koiti Araki
Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, Av. Prof. Lineu Prestes 748, Butanta, 05508-000 São Paulo, Brazil
Sergi Garcia-Segura
Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment, School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, AZ 85287-3005, USA
Gino Picasso
Laboratory of Physical Chemistry Research, Faculty of Sciences, National University of Engineering, Av. Tupac Amaru 210, 15333 Lima, Peru
Gas sensors are fundamental for continuous online monitoring of volatile organic compounds. Gas sensors based on semiconductor materials have demonstrated to be highly competitive, but are generally made of expensive materials and operate at high temperatures, which are drawbacks of these technologies. Herein is described a novel ethanol sensor for room temperature (25 °C) measurements based on hematite (α‑Fe2O3)/silver nanoparticles. The AgNPs were shown to increase the oxide semiconductor charge carrier density, but especially to enhance the ethanol adsorption rate boosting the selectivity and sensitivity, thus allowing quantification of ethanol vapor in 2–35 mg L−1 range with an excellent linear relationship. In addition, the α-Fe2O3/Ag 3.0 wt% nanocomposite is cheap, and easy to make and process, imparting high perspectives for real applications in breath analyzers and/or sensors in food and beverage industries. This work contributes to the advance of gas sensing at ambient temperature as a competitive alternative for quantification of conventional volatile organic compounds.
