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以Cr(NO3)3·9H2O和NH3·H2O为原料在水体系中进行化学反应并在空气中烧结,制备了直径为20～30 nm的氧化铬纳米颗粒.利用X-射线衍射(XRD)、透射电子显微镜(TEM)和扫描电子显微镜(SEM)对该纳米颗粒的结构和形貌进行了表征.XRD谱图表明Cr2 O3纳米颗粒为三方晶相.利用BET法计算Cr2 O3纳米颗粒的比表面积为39.38 m2·g-1.利用X-射线光电子能谱(XPS)观察到Cr2 O3纳米颗粒表面存在丰富的表面吸附氧,这些吸附氧可以介导目标分子的响应.制备了基于Cr2 O3纳米粒子的厚膜传感器,用于在250℃的操作温度和10 ppm的检测限下检测丙酮、甲醇、乙醇、1-丙醇和甲苯.为了便于实际应用,测试了传感器的时间稳定性,一年后传感器的响应保持在95％,时间常数保持在97％.同时,还测试了传感器对环境湿度的响应,这种响应可忽略不计.最后,分析了与所用静态方法相关的实验误差.“,”Chromium oxide nanoparticles with diameters of 20 ～30 nm were synthesized by a chemical reaction of Cr(NO3)3·9H2O and NH3·H2O in an aqueous system followed by calcinations in air. The structures and morphologies of these nanoparticles were characterized by X-ray diffraction ( XRD) , trans-mission electron microscopy ( TEM) and scanning electron microscopy ( SEM) . The XRD patterns illus-trate that the crystallized Cr2 O3 nanoparticles are in the trigonal phase. Using the BET method, we calcu-lated the specific surface area of Cr2 O3 nanoparticles as 39. 38 m2 ·g-1 . Abundant surface adsorbed oxy-gen on the surface of Cr2 O3 nanoparticles was observed by X-ray photoelectron spectroscopy ( XPS ) , which is believed to mediate the response to the target molecules. Thick film sensors based on Cr2 O3 nan-oparticles were fabricated in order to detect acetone, methanol, ethanol, 1-propanol and toluene with a detection limit of 10 ppm at a 250℃ operating temperature. For practical application, we tested the time stability of the sensor, with the response remaining at 95％ and the time constant at 97％ after one year of storage. We also tested the sensor response to environmental humidity which is negligible. Finally, the experimental errors associated with the static method were analyzed.