Synthesis of the oxide $ NiSb_{2} %$ O_{6} $ and its electrical characterization in toxic atmospheres for its application as a gas sensor

Abstract In this work, nanoparticles of the trirutile-type oxide $ NiSb_{2} %$ O_{6} $ were synthesized for its application as a gas sensor using the colloidal method assisted by microwave radiation. The crystalline evolution of the powders was analyzed by X-ray diffraction, finding the phase $ NiSb...
Ausführliche Beschreibung

Abstract In this work, nanoparticles of the trirutile-type oxide $ NiSb_{2} %$ O_{6} $ were synthesized for its application as a gas sensor using the colloidal method assisted by microwave radiation. The crystalline evolution of the powders was analyzed by X-ray diffraction, finding the phase $ NiSb_{2} %$ O_{6} $ at 600 °C. SEM micrographs revealed the growth of microspheres, microrods, and irregularly shaped particles. Using TEM, the average size of the nanoparticles was calculated at ~ 17.1 nm. For dynamic tests, pellets and thick films were made from the powders calcined at 600 °C. For the thick films, alternating current was used at frequencies of 0.1 and 1 kHz in $ C_{3} %$ H_{8} $ and $ CO_{2} $ atmospheres at 360 °C, where the material’s sensitivity magnitude in $ CO_{2} $ was ~ 2.61% (0.1 kHz) and ~ 2.97% (1 kHz). In contrast, for $ C_{3} %$ H_{8} $, the sensitivity was ~ 6.69% (0.1 kHz) and ~ 5.12% (1 kHz) on average. For the pellets, direct current signals and volumetric flow rates of 100, 150, and 200 $ cm^{3} $/min of CO at 200 °C were applied, where the sensitivities were ~ 24.37, ~ 35.33, and ~ 40.77%, respectively. In each test, the sensitivity visibly increased when the gases were injected. Likewise, the response and recovery times decreased when the frequency and gas concentration increased. The results obtained for the trirutile-type oxide $ NiSb_{2} %$ O_{6} $, which showed good stability, efficiency, and high sensitivity in $ CO_{2} $, $ C_{3} %$ H_{8} $, and CO atmospheres, make it ideal as a toxic gas sensor. Ausführliche Beschreibung