Co ions doping enhances n-butanol sensing performance of In2O3 nanospheres

In this work, In2O3 nanospheres were synthesized using urea as a carbon template and modified with Co ions. The synthesized materials were characterized using various instruments to obtain information about the elemental composition and morphology of the materials. The results showed that Co ions replaced the lattice position of In ions and synthesized nanospheres aggregated from 20 nm particles. The results of gas sensitivity tests on all the samples showed that the response to 50 ppm n-butanol at 250 °C reached 540 when Co was doped up to 5 at%. In comparison, the sensor showed very low response to benzene gas with good selectivity. The high response of the sensor to n-butanol is due to the increase in vacancy oxygen content and redox reactions due to the multivalent nature of Co ions. The article concludes with a detailed analysis of the sensing mechanism. © 2024 Elsevier B.V.