Design of Selective Gas Sensors Using Additive-Loaded In ₂O ₃ Hollow Spheres Prepared by Combinatorial Hydrothermal Reactions

Abstract

A combinatorial hydrothermal reaction has been used to prepare pure and additive (Sb, Cu, Nb, Pd, and Ni)-loaded In ₂O ₃ hollow spheres for gas sensor applications. The operation of Pd- and Cu-loaded In ₂O ₃ sensors at 371 °C leads to selective H ₂S detection. Selective detection of CO and NH ₃ was achieved by the Ni-In ₂O ₃ sensor at sensing temperatures of 371 and 440 °C, respectively. The gas responses of six different sensors to NH ₃, H ₂S, H ₂, CO and CH ₄ produced unique gas sensing patterns that can be used for the artificial recognition of these gases.