Abstract: Cobalt oxide (Co3O4) is a p-type semiconductor that can be used as a gas-sensing material. Non-metallic boron (B) has the characteristic of absorbing electrons. Doped it with p-type semiconductor gas-sensing material can increase the concentration of hole carrier of the material, thus improving the gas-sensing property of the material. In this paper, B-doped Co3O4 sea urchins microspheres were successfully prepared by low-temperature one-step hydrothermal method with cobalt nitrate hexahydrate (Co(NO3)2·6H2O), boric acid (H3BO3) and urea (Co(NH2)2) as raw materials. The structure of Co3O4 before and after boron doped was characterized by X-ray diffractometer (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectrometer (XPS) and Raman spectrometer (Raman), to explore the influence of boron doped on its gas-sensing performance. The results showed that boron doped significantly enhanced the gas sensing properties of Co3O4. When the doped molar ratio was Co: B= 8:1, the optimal working temperature of B-Co3O4 for 1×105μg/L ethanol was 180℃, and the sensitivity response reached 26.8, which was 4.4 times that of pure Co3O4 under the same conditions. B-Co3O4 is an excellent gas sensing material with good sensitivity, selectivity and stability under low operating temperature.

Key words: boron doped, cobalt oxide, gas-sensing properties, gas sensing mechnism

摘要： 四氧化三钴（Co3O4）是一种p型半导体，可作为气体传感材料。非金属硼（B）具有吸电子特性，将其与p型半导体气敏材料进行掺杂，可增加材料的空穴载流子浓度，从而提高材料的气敏性能。本文以六水合硝酸钴（Co(NO3)2·6H2O）、硼酸（H3BO3）和尿素（CO(NH2)2）为原料，采用低温一步水热法成功制备了B掺杂Co3O4海胆状微球。通过X射线衍射仪（XRD）、扫描电镜（SEM）、透射电镜（TEM）、X射线光电子能谱仪（XPS）和拉曼光谱仪（Raman）对掺杂B前后的Co3O4进行结构表征，探究B掺杂对其气敏性能的影响。结果表明，B掺杂对Co3O4材料的气敏性能有明显的强化作用。当掺杂摩尔比为Co：B=8：1时，B-Co3O4对1×105μg/L乙醇的最佳工作温度为180℃，灵敏度响应达到26.8，是相同条件下纯Co3O4的4.4倍。B-Co3O4在较低的工作温度下，具有良好的灵敏度、选择性和稳定性，是一种性能优良的气敏材料。

关键词: 硼掺杂, 四氧化三钴, 气敏特性, 气敏机制