摘要
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 Co_3O_4 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 Co_3O_4 hollow nanospheres were controlled by changing the concentration of precursor and aging time. The results show that the Co_3O_4 hollow nanospheres with diameter of 500 nm composed by 40 nm Co_3O_4 nanoparticles can be synthesized with 0.1 mol/L precursor and aging for 48 h. The surface of nanospheres is porous structure. The synthesized Co_3O_4 hollow nanospheres sensor have good gas response to 100×10~(-6)-0.5×10~(-6)NH_3 at room temperature. The gas sensitivity to 100×10~(-6)NH_3 reaches 155.8% and the response time is 1.3 s. The limit level of this gas sensor to NH_3 is 0.5×10~(-6).
引文
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