所制备的ZnO呈六方体状，通过水热反应使其与CuO形成了双层结构，基于

所制备的ZnO呈六方体状，通过水热反应使其与CuO形成了双层结构，基于该形态以及两者晶格常数相近因此容易形成PN异质结。而两者高负电性和碱性使其更容易在常温条件下发生反应，这也是传感器能在常温条件下仍然能具备高灵敏度的原因，其次由于ZnO和CuO之间功函数的差异，有利于电荷转移。在有氧的情况下，将氧分子吸附在纳米材料表面并发生释放出不同价态的O2-和O-，当处于富二氧化碳环境时，氧离子与CO2分子结合释放电子，直至饱和，并且该过程可逆。

The prepared ZnO is hexagonal in shape and forms a double-layer structure with CuO through hydrothermal reaction. Based on this morphology and the similar lattice constants of the two, it is easy to form a PN heterojunction. The high negativity and alkalinity of both make it easier for them to react at room temperature, which is also why the sensor can still have high sensitivity at room temperature. Secondly, due to the difference in work functions between ZnO and CuO, it is conducive to charge transfer. In the presence of oxygen, oxygen molecules are adsorbed on the surface of nanomaterials and release O2- and O - with different valence states. When in a carbon dioxide rich environment, oxygen ions combine with CO2 molecules to release electrons until saturation, and this process is reversible.

The prepared ZnO is hexagonal, and it forms a double-layer structure with CuO through hydrothermal reaction. Based on this morphology and the similar lattice constants, it is easy to form PN heterojunction. The high electronegativity and alkalinity of ZnO and CuO make it easier to react at room temperature, which is why the sensor can still have high sensitivity at room temperature. Secondly, due to the difference of work function between ZnO and CuO, it is beneficial to charge transfer. In the presence of oxygen, oxygen molecules are adsorbed on the surface of nano-materials and release O2- and O- with different valence states. When in a CO2-rich environment, oxygen ions combine with CO2 molecules to release electrons until they are saturated, and this process is reversible.