石墨烯-Au纳米复合体系的构筑及其光限幅效应
Structure and optical limiting effect of graphene nanosheets attached Au-DT-CTAB
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摘要: 首先对Au纳米颗粒进行巯基修饰,再对其采用表面活性剂十六烷基三甲基溴化铵(CTAB)进行二级修饰,并将其自组装负载于石墨烯纳米毯(GNSs)上。通过紫外-可见吸收光谱证明Au纳米颗粒在石墨烯纳米毯(GNSs)上的成功负载。通过透射电子显微镜探明其微观结构,表明Au纳米颗粒在石墨烯纳米毯上呈现局部规整排列,其原因与石墨烯纳米毯自身的平整结构有关。采用开孔Z-扫描技术研究了负载Au纳米颗粒的石墨烯纳米毯的非线性光限幅性能,结果表明:其光限幅起始阈值明显下降,在低入射能量时即产生光限幅特性。并发现入射光强增大时非线性散射增强,说明非线性散射是产生复合体系的非线性光限幅效应的重要机理。Abstract: First, the thiol modification of Au nanoparticles was carried out, then two grade modification was carried out with sixteen alkyl three methyl bromide(CTAB), and its self assembly load on grapheme nano blanket(GNSs). The successful loading of Au nanoparticles on grapheme sheets(GNSs) was demonstrated by UV Vis absorption spectra. The microstructure was proved by transmission electron microscopy. It showed that the Au nanoparticles were arranged in the grapheme nano blanket, because of its structure of grapheme nano blanket. The nonlinear optical limiting properties of grapheme nano particles with load Au nanoparticles were studied by using the Z-scanning technique. The resuls show that the threshold of optical limiting threshold is significantly decreased. The optical limiting characteristic is produced while in the low incident energy, and the nonlinear scattering enhancement is found when the incident light intensity increases. So nonlinear scattering is an important mechanism of nonlinear optical limiting effect in composite systems.