Dual Selective Gas Sensor Based on Delafossite CuCoO₂ with Instantaneously Attenuated Response to Amine at Room Temperature

Gas sensors with dual selectivity are highly desirable for the manufacture of high-performance, miniaturized, and low-cost sensor prototypes. In this work, we introduce a dual selective gas sensor with a temperature-dependent sensing behavior based on delafossite CuCoO₂ microcrystals. At room temperature, the sensor exhibits an obvious response to amine with a good selectivity to n-BuNH₂, while the sensor displays a special selective response to triethylamine (TEA) at 250 °C. This dual sensing behavior makes it convenient for analyzing the mixture gases of n-BuNH₂ and TEA via constructing the sensor array with a detection deviation below 10%. The sensor can also be applied to evaluate the spoilage of meat that is operated at room temperature. The temperature-dependent sensing behavior can be attributed to the different adsorption behaviors of gas molecules on CuCoO₂ along with the different oxidation abilities of oxygen ions generated at different temperatures.