title: CO Gas Sensing Properties of Pure and Cu-Incorporated SnO₂ Nanoparticles: A Study of Cu-Induced Modifications.
abstract: Pure and copper (Cu)-incorporated tin oxide (SnO₂) pellet gas sensors with characteristics provoking gas sensitivity were fabricated and used for measuring carbon monoxide (CO) atmospheres. Non-spherical pure SnO₂ nano-structures were prepared by using urea as the precipitation agent. The resultant SnO₂ powders were ball milled and incorporated with a transition metal, Cu, via chemical synthesis method. The incorporation is confirmed by high-resolution transmission electron microscope (HRTEM) analysis. By utilizing Cu-incorporated SnO₂ pellets an increase in the CO sensitivity by an order of three, and a decrease in the response and recovery times by an order of two, were obtained. This improvement in the sensitivity is due to two factors that arise due to Cu incorporation: necks between the microparticles and stacking faults in the grains. These two factors increased the conductivity and oxygen adsorption, respectively, at the pellets' surface of SnO₂ which, in turn, raised the CO sensitivity.
authors.affiliation: Departamento de Ingeniería Eléctrica-SEES, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, CINVESTAV-IPN, 14740 Apartado, Mexico. krishnakarthik.tv@gmail.com.
authors.forename: Tangirala Venkata Krishna
authors.initials: TV
authors.lastname: Karthik
authors.affiliation: Departamento de Ingeniería Eléctrica-SEES, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, CINVESTAV-IPN, 14740 Apartado, Mexico. molvera@cinvestav.mx.
authors.forename: María de la Luz
authors.initials: Mde L
authors.lastname: Olvera
authors.affiliation: Departamento de Ingeniería Eléctrica-SEES, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, CINVESTAV-IPN, 14740 Apartado, Mexico. amaldo@cinvestav.mx.
authors.forename: Arturo
authors.initials: A
authors.lastname: Maldonado
authors.affiliation: Área académica de Computación y Electrónica, ICBI, Universidad Autónoma del Estado de Hidalgo, Mineral de la Reforma, 56092 Hidalgo, Mexico. gpozos@uaeh.edu.mx.
authors.forename: Heberto
authors.initials: H
authors.lastname: Gómez Pozos
keywords: CO; copper; doping; gas sensing; tin oxide