###### Abstract  
In this work, powders of NiSb\({}_{2}\)O\({}_{6}\) were synthesized using a simple and economical microwave-assisted wet chemistry method, and calcined at 700, 800, and 900 \({}^{\circ}\)C. It was identified through X-ray diffraction that the oxide is a nanomaterial with a tritrutile-type structure and space group P\({}_{42}\)/mm (136). UV-Vis spectroscopy measurements showed that the bandgap values were at -3.10, -3.14, and -3.23 eV at 700, 800, and 900 \({}^{\circ}\)C, respectively. Using scanning electron microscopy (SEM), irregularly shaped polyhedral microstructures with a size of -154.78 nm were observed on the entire material's surface. The particle size was estimated to average -92.30 nm at the calcination temperature of 900 \({}^{\circ}\)C. Sensing tests in static atmospheres containing 300 ppm of CO at 300 \({}^{\circ}\)C showed a maximum sensitivity of -72.67. On the other hand, in dynamic atmospheres at different CO flows and at an operating temperature of 200 \({}^{\circ}\)C, changes with time in electrical resistance were recorded, showing a high response, stability, and repeatability, and good sensor efficiency during several operation cycles. The response times were -2.77 and -2.10 min to 150 and 200 cm\({}^{3}\)/min of CO, respectively. Dynamic tests in propane (C\({}_{3}\)H\({}_{8}\)) atmospheres revealed that the material improved its response in alternating current signals at two different frequencies (0.1 and 1 kHz). It was also observed that at 360 \({}^{\circ}\)C, the ability to detect propane flows increased considerably. As in the case of CO, NiSb\({}_{2}\)O\({}_{6}\)'s response in propane atmospheres showed very good thermal stability, efficiency, a high capacity to detect C\({}_{3}\)H\({}_{8}\), and short response and recovery times at both frequencies. Considering the great performance in propane flows, a sensor prototype was developed that modulates the electrical signals at 360 \({}^{\circ}\)C, verifying the excellent functionality of NiSb\({}_{2}\)O\({}_{6}\). Keywords:NiSb\({}_{2}\)O\({}_{6}\); pellets; thick films; dynamic response; electronic circuit +
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and the emergence of various respiratory diseases [2; 3]. An alternative to somehow counteract these problems is to constantly control and monitor the concentration of toxic gases by designing simple electronic devices that meet the features of high-performance environmental gas sensors [4; 5]. Several research groups and sensor manufacturing companies have worked on a wide variety of materials, mainly semiconductors, that could act as detectors for different polluting gases [4; 6]. With such materials, toxic gas (such as CH\({}_{4}\), LPG, and H\({}_{2}\)) leak detectors have been manufactured to monitor the emission of pollutants thrown by automobiles, etc. [6]. Nowadays, there is a great variety of gas sensors that can be classified according to their electrolytic, catalytic, electrochemical, and semiconductor properties [7; 8]. The latter have been the most studied due to their excellent detection properties, having a high degree of sensitivity, good efficiency, wide detection of different gases (selectivity), as well as good performance at high operating temperatures (200-400 \({}^{\circ}\)C) in unsuitable humidity conditions [4; 5; 6]. To determine if a material can be used as a gas detector, it must detect low gas concentrations, detect a specific gas (selectivity), obtain a signal in the presence of the test gas in a relatively short time, and return to its initial state when finishing the detection process [9; 10]. It has been reported in the literature that the most effective materials that can be applied as gas detectors are semiconductor metal oxides because they possess great advantages, such as thermal stability and high sensitivity [9; 11]. It has been recognized that the detection ability of semiconductor oxides is based on reduction-oxidation reactions that occur between the material's surface and the test gas [11; 12].