Owing to highly toxic and volatile organophosphates (OPs), DMMP has been selected as simulant in laboratory for analyzing the concentration of OPs, because they have similar chemical structure and physical/chemical properties. Therefore, it is of utmost importance to develop advanced techniques for DMMP detection, especially using metal oxides as sensing materials. Here, a gas template strategy was proposed to prepare CuO nanoframes possessing porous structure and abundant oxygen vacancies (34.7 %), where the introduction of citric acid (CA) plays an important role in forming this unique structure. Notably, the CuOOV-2 sensor exhibits the response value of 2.4 to 100 ppm DMMP at relatively low working temperature of 160 °C, good selectivity and repeatability. The DMMP sensing results reveal that DMMP sensing mechanism consists the traditional adsorbed oxygen mechanism and catalysis mechanism. This work introduces a novel approach to design metal oxides with unique property, providing the way for fabrication of high-performance gas sensors.

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