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采用硝酸铜、硝酸铈为先驱物 ,乙二醇作溶剂 ,以改进的溶胶 凝胶法制备了纳米结构CuO/CeO2 稀土复合氧化物 .表征结果表明 ,制得的纳米材料的粒径为 15nm左右 ,而二次分布在2 0～ 5 0nm之间 .考察了焙烧温度、不同CuO含量复合材料敏感元件对CO ,H2 ,C2 H5OH ,C6 H6等气体的灵敏度影响 .从实验得出 ,最佳焙烧温度为 6 0 0℃ ,CuO含量为 12 % ,掺入少量贵金属气敏性质得到进一步改进 ,是由掺杂质和复合物之间电子和化学叠加效应所致 .通过制备过程参数控制 ,裁剪出高热稳定和最佳组成的纳米复合材料 ,对监测环境有毒和可燃气体具有较高灵敏度和选择性 .研究结果也为稀土和过渡金属复合氧化物催化剂的制备与催化性质的研究提供了有益的借鉴 .
Nanocrystalline CuO / CeO2 rare earth composite oxides were prepared by the improved sol-gel method using copper nitrate, cerium nitrate as precursors and ethylene glycol as solvent.The characterization results showed that the prepared nanomaterials had a particle size of about 15 nm , And the secondary distribution was between 20 and 50 nm.The effects of calcination temperature and different CuO content on the sensitivities of CO, H2, C2 H5OH and C6 H6 gas sensors were investigated.The best calcination At a temperature of 600 ℃ and a CuO content of 12%, the gas-sensing properties of a small amount of noble metal were further improved by the electron and chemical superposition effects of the dopants and the complexes. By control of the preparation process parameters, High thermal stability and the best composition of nanocomposites with high sensitivity and selectivity for the monitoring of toxic and combustible gases in the environment.The results also provide a useful reference for the preparation and catalytic properties of rare earth and transition metal complex oxide catalysts .