The introduction of surface defects in sensing materials is an important means to improve sensor performance. In this work, we design a simple one-step route to synthesize ZnO-ZnSe without any template or surfactant, and obtain ZnO-ZnSe hollow spherical composite with a diameter of ∼ 200 nm. The shell of the hollow spheres is assembled by nanoparticles with a lot of surface defects after sintering at 800 °C in N₂ atmosphere. The surface defects can promote the sensing materials release more electrons and facilitate the reaction of oxygen ions on the material surface. It is beneficial to the adsorption of NO₂ on sensing materials for enhancing the sensing performance. The composite shows excellent sensitivity for 10 ppm NO₂ at 170 °C, which is 5.32 times that of pure ZnO. And the sensor can recover quickly within 28 s after responding to NO₂. It is also satisfactory for the sensor to detect the lowest concentration of 100 ppb. The chemical characterizations such as DRS, PL, XPS, GC–MS, and Kelvin probe are used, combined with the calculation of DFT theory to further explore the synergy effect of the formation of ZnO and ZnSe heterojunction and the surface defects caused by high-temperature sintering on the improvement of sensor performance.

在传感材料中引入表面缺陷是提高传感器性能的重要手段。在这项工作中，我们设计了一种简单的一步合成 ZnO-ZnSe 的路线，无需任何模板或表面活性剂，并获得直径为 ∼ 200 nm 的 ZnO-ZnSe 空心球形复合材料。空心球的外壳由具有大量表面缺陷的纳米粒子在N ₂气氛中在800℃下烧结后组装而成。表面缺陷可以促进传感材料释放更多的电子，促进氧离子在材料表面的反应。有利于NO ₂在传感材料上的吸附，提高传感性能。该复合材料对 10 ppm NO _{2表现出出色的灵敏度}在 170 °C 时，是纯 ZnO 的 5.32 倍。并且传感器在响应NO ₂后可在28 s内迅速恢复。传感器检测到 100 ppb 的最低浓度也令人满意。利用DRS、PL、XPS、GC-MS、开尔文探针等化学表征，结合DFT理论计算，进一步探索ZnO和ZnSe异质结形成的协同效应以及高-温度烧结对传感器性能的提高。