Room temperature triethylamine gas sensor with excellent performances based on novel porous CuO foam via a simple and facile route

Monitoring of explosive and toxic triethylamine (TEA) is essential for environmental safety and human health. However, high sensitivity detection of TEA remains a huge challenge at low temperature or even room temperature. Here, we developed a CuO porous foam-based gas sensor for TEA detection at room temperature by defect engineering of oxygen vacancies. The CuO porous foam with rich surface oxygen vacancies have been synthesized through a sol-gel autocombustion method, and the formation mechanism of porous foam structure and rich oxygen vacancies of CuO have been investigated by various characterization methods. Moreover, the fabricated CuO foam gas sensor reveals the high response of 140.0 for 50 ppm TEA, a low detection limit of 0.5 ppm, excellent selectivity, good stability and repeatability at room temperature, which are ascribed to porous structure and rich surface oxygen vacancies of CuO foam. Importantly, the surface redox reaction model and density function theoretical calculation have been applied to deeply explore the sensing mechanism. This work can not only realize the ultra-sensitive sensing of TEA at room temperature, but also provide a novel strategy for the design of other ideal performance sensors at low operating temperatures.