丁基罗丹明B-AuI4-缔合纳米粒子体系的极谱猝灭效应研究

在0．1mol／LH2SO4介质中，丁基罗丹明B(RBB)在-0．59伏产生1个单扫描极谱峰。当有AuI^-4存在时，AuI^-4与RBB^ 主要通过静电引力形成疏水性的AuI4—2RBB缔合物分子。AuI4—2RBB存在较强的分子间作用力和疏水作用力而生成紫红色的(AuI4—RBB)n纳米微粒，在470nm处产生1个瑞利散射峰，在610nm处产生1个共振瑞利散射峰；而在-0．59伏处的极谱峰降低。这是由于该紫红色复合纳米微粒形成所致。当纳米微粒体系加入乙醇后，体系的瑞利散射峰和共振瑞利散射峰消失，极谱峰、同步荧光峰和颜色恢复，由于乙醇而致使紫红色的(AuI4-RBB)n纳米微粒分解为红色AuI4—RBB分子。研究结果表明，紫红色(AuI4-RBB)。纳米粒子的形成是其极谱猝灭和共振瑞利散射效应的根本原因。

Polarographic Quenching and Resonance Rayleigh Scattering Effects of (AuI4-RBB)n Association Nanoparticles

There is a polarographic peak at-0.59 V vs. SCE for rhodamine B butyl ester(RBB)in the medium of 0.1 mol/L H2SO4.The AuI-4 and RBB+ were combined into a hydrophobic association molecule of AuI4-RBB by means of electrostatic attraction.There were stronger Van de Waals forces and hydrophobic forces among AuI4-RBB molecules.So it formed (AuI4-RBB)n association nanoparticles in red-violet that exhibited a strong resonance rayleigh scattering(RRS)peak at 610 nm and the RRS effect.The polargraphic quenching at-0.58 V was owing to that the RBB molecules could not be reduced at the surface of DME,which was in the body of the association nanoparticles.The (AuI4-RBB)n association nanoparticles could be decomposed into AuI4-RBB association molecules by alcohol.So,the scattering peaks disappeared.The polarographic peak and the fluorescence peak re-appeared.The color comes back from the red-violet to the red.The results demonstrated that the formation of (AuI4-RBB)n association nanoparticles leaded to its polarographic quenching effect and the RRS effect.