Co_3O_4中空纳米球的可控制备及气敏性能

Preparation of Co_3O_4 hollow nanospheres and gas sensing properties

以碳纳米球为模板,采用硬模板法制得多孔Co_3O_4中空纳米球。分别采用SEM、XRD、FTIR、BET和XPS对Co_3O_4纳米球的形貌和结构进行表征。通过改变前驱体浓度和陈化反应时间调控Co_3O_4中空纳米球的空间结构及气敏性能。结果表明:在前驱体浓度为0.1mol/L、陈化时间为48h时,得到的Co_3O_4中空纳米球的表面呈疏松多孔结构。Co_3O_4中空纳米球直径约为500nm,由40nm的Co_3O_4纳米粒子组成。室温下,由该材料组装的气敏传感器对浓度为100×10^(-6)～0.5×10^(-6)的NH_3有较好的气敏性能;对浓度为100×10^(-6)的NH_3响应灵敏度高达155.8%,响应时间为1.3s。该气体传感器对NH_3的最低检测限为0.5×10^(-6)。

The porous Co3O4 hollow nanospheres were synthesized via hard template method by a carbon spheres templated strategy.The morphology and structure of materials were studied by SEM,XRD,FTIR,BET and XPS.The structure and gas sensing properties of Co3O4 hollow nanospheres were controlled by changing the concentration of precursor and aging time.The results show that the Co3O4 hollow nanospheres with diameter of 500nm composed by 40nm Co3O4 nanoparticles can be synthesized with 0.1mol/L precursor and aging for 48h.The surface of nanospheres is porous structure.The synthesized Co3O4 hollow nanospheres sensor have good gas response to 100×10^-6-0.5×10^-6 NH3 at room temperature.The gas sensitivity to 100×10^-6 NH3 reaches 155.8% and the response time is 1.3s.The limit level of this gas sensor to NH3 is 0.5×10^-6.