离子液体辅助合成α-Fe_2O_3纳米棒及其气敏性能

Ionic Liquid-Assisted Synthesis of α-Fe_2O_3 Nanorods and Its Sensing Performance

采用水热合成法和热生长法,以六水氯化铁(Fe Cl_3·6H_2O)为铁源、氢氧化钠(Na OH)为沉淀剂、离子液体1-丁基-3-甲基咪唑氯化物([Bmim]Cl)为表面活性剂,两步合成了α-Fe_2O_3纳米棒,研究了沉淀剂Na OH和[Bmim]Cl添加量对产物形貌结构的影响,并且研究不同[Bmim]Cl添加量合成的α-Fe_2O_3纳米棒的气敏性能,结合能带理论分析了传感器的气敏响应机理。结果表明:当添加0.541 g Fe Cl_3·6H_2O和0.8 g Na OH,[Bmim]Cl的量为1 mmol时可以生成形貌均匀,分散性好,比表面积大的纯相α-Fe_2O_3纳米棒。气敏测试结果表明,其在工作温度为200℃下对5μL·L^(–1)的硫化氢气体的灵敏度达到8.4,检测范围达到0.1～20μL·L^(–1),并且具有良好的稳定性和选择性,有望应用于工业和生活中低浓度的硫化氢气体检测。

α-Fe2O3 nanorods were synthesized via hydrothermal synthesis and thermal growth with ferric chloride hexahydrate(FeCl3·6H2O)as an iron source,sodium hydroxide(NaOH)as a precipitating agent and 1-butyl-3-methylimidazolium chloride([Bmim]Cl)as a surfactant.The influence of concentration of NaOH/[Bmim]Cl on the morphology of the specimens was investigated.The gas sensitivity and response mechanism ofα-Fe2O3 nanorods synthesized at different amounts of ionic liquids were analyzed based on the band theory.The results show that pureα-Fe2O3 nanorods with uniform morphology,good dispersibility and large specific surface area can be formed when 0.541 g FeCl3·6H2O and 0.8 g NaOH are added and the amount of[Bmim]Cl is 1 mmol.The sensitivity to 5μL·L–1 hydrogen sulfide gas is 8.4,and the detection range is 0.1–20μL·L–1,operating at 200℃.Theα-Fe2O3nanorods as a sensor have a good stability and a selectivity for hydrogen sulfide detection at low concentrations.