微生物吸附-化学还原法制备金钯合金纳米线

摘要

The gold and palladium nanowires (Au-Pd NWs) were prepared from the waste gold and palladium catalysts as raw materials by microbial adsorption and chemical reduction method. In the preparative process, Escherichia coli (ECCs) were used as bio-template, ascorbic acid (AA) as a reducing agent, and cetyltrimthyl ammonium bromide (CTAB) as a protective agent, respectively. SEM, TEM, XRD and XPS spectroscopy and other technologies were employed to characterize the obtained Au-Pd NWs samples. The experimental results show that a large number of linear nanowires can be generated by adding 0.5 g/L ECCs, 5.0 mmol/L CTAB, 1.0 mmol/L AA, when the molar ratio of gold to palladium is controlled by 3:1~1:3. The morphology is the best when the mole ratio of Au/Pd is 1:1.The concentration of CTAB has great influence on gold and palladium nanowires diameter. The characterization results also showed that the Au-Pd NWs displayed an alloy nanowire profile in face cubic crystal and had polycrystalline structure with 0.232 nm of lattice spacing.%采用微生物吸附-化学还原法，失效金、钯催化剂为原料，以大肠杆菌为模板、十六烷基三甲基溴化铵(CTAB)为保护剂、抗坏血酸为还原剂制备金钯合金纳米线(Au-Pd NWs)，用SEM、TEM、XPS、XRD等技术对金钯合金纳米线进行了表征。结果表明，在大肠杆菌菌粉量为0.5 g/L、CTAB量为5.0 mmol/L、抗坏血酸浓度为1.0 mmol/L反应条件下，当金钯摩尔比控制在3：1~1：3之间，均有较大量纳米线生成，金钯摩尔比为1：1时形貌最佳；CTAB浓度对金钯合金纳米线直径影响较大。表征结果显示，金钯纳米线的晶面间距为0.232 nm，是一种具有面心立方(fcc)、多晶结构的双金属合金纳米线。