SnO2中空微球的制备与气敏性能

在不加任何表面活性剂情况下，采用磺化的聚苯乙烯（PS）微球为模板，二水结晶二氯化锡（SnCl₂·2H₂O）为锡源，成功制得SnO₂中空微球。利用X射线衍射仪（XRD）、扫描电镜（SEM）、高分辨透射电镜（HRTEM）和氮气吸附脱附仪（BET）对材料的结构和形貌进行了表征，研究并讨论了温度、乙醇浓度等因素对SnO₂纳米颗粒及SnO₂中空微球气敏性能的影响。结果显示，SnO₂中空微球的比表面积为48.49m²/g，比SnO₂纳米颗粒的比表面积（21.94m²/g）提升了1.21倍。比表面积增加有助于SnO₂材料表面吸附更多被测气体以提升表面化学反应，进而提升气敏性能。在260℃下，SnO₂中空微球对200μL/L乙醇的灵敏度为66.26，与SnO₂纳米颗粒相比（51.34），气敏性能提高了0.29倍。

Synthesis of hollow SnO2 microspheres and their enhanced sensing properties to ethanol

SnO₂ hollow microspheres were successfully synthesized using sulfonated PS microspheres as a template and stannous chloride dihydrate (SnCl₂·2H₂O) as tin source, without using any surfactants. The structure and morphology of the obtained samples were characterized by XRD, SEM, HRTEM and BET. The effects of working temperature, ethanol concentration and other factors on the sensitivity were discussed. The results indicated that the SnO₂ hollow microspheres had high specific surface area of 48.49m²/g, which was 1.21 times higher than the specific surface area (21.94m²/g) of SnO₂ nanoparticles. The increase of specific surface area contributed to the adsorbtion of more target gases on the SnO₂ surface to enhance surface chemical reaction, and further improved the gas sensing properties. The sensor based on the SnO₂ hollow microspheres exhibited good gas-sensing properties, and the sensitivity to 200μL/L ethanol is 66.26 at the optimum operating temperature (260℃), which was 0.29 times higher than that of the SnO₂ nanoparticles (51.34).