Hierarchical porous and non-porous ZnO microflowers have been successfully fabricated by hydrothermal method. Their crystal structure, morphology and gas-sensing properties were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), and chemical gas sensing intelligent analysis system (CGS). Compared with hierarchical non-porous ZnO microflowers, hierarchical porous ZnO microflowers exhibited ultra-high sensitivity with 50ppm ethanol at 260 ^oC and the response is 110, which is 1.8 times higher than that of non-porous ZnO microflowers. Moreover, the lowest concentration limit of hierarchical porous ZnO microflowers (non-porous ZnO microflowers) to ethanol is 0.1 (1) ppm, the response value is 1.6 (1).

通过水热法成功制备了多层多孔和无孔ZnO微花。通过X射线衍射（XRD），扫描电子显微镜（SEM）和化学气体传感智能分析系统（CGS）研究了它们的晶体结构，形态和气敏特性。与分层无孔ZnO微型花相比，分层多孔ZnO微型花在260 ^o C的50ppm乙醇中表现出超高的灵敏度，响应为110，是非多孔ZnO微型花的1.8倍。另外，分级多孔ZnO微花（无孔ZnO微花）对乙醇的最低浓度极限为0.1（1）ppm，响应值为1.6（1）。