聚苯胺在银和金胶体上的表面增强共振拉曼散射

Surface-enhanced resonance Raman scattering of polyaniline on silver and gold colloids.

作者信息

Izumi Celly M S, Andrade Gustavo F S, Temperini Marcia L A

机构信息

Laboratório de Espectroscopia Molecular, Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo, CP 26.077, CEP 05513-970, São Paulo, SP, Brazil.

出版信息

J Phys Chem B. 2008 Dec 25;112(51):16334-40. doi: 10.1021/jp805373s.

DOI:10.1021/jp805373s

PMID:19368009

Abstract

The interaction of emeraldine base (PANI-EB) with silver and gold colloids was probed by using Surface-Enhanced Resonance Raman Scattering (SERRS) at 3 different exciting radiations. Due to the great sensitivity of SERRS technique the detection limit of PANI-EB concentration was ca. 2 x 10(-7) mol L(-1) in Ag and Au colloidal suspensions. The UV-vis-NIR spectra of metal colloids in function of PANI-EB concentrations showed that gold colloids present a higher degree of aggregation than silver colloids. SERRS of PANI-EB on metal colloids allowed the study of the polymeric species formed primarily on the metallic surface. The polymer formed after the adsorption of PANI-EB on metallic nanoparticles is strongly dependent on the nature of the metal colloids. The oxidation of PANI-EB to pernigraniline occurred for silver colloids, while a doping process of PANI-EB on Au nanoparticles was evidenced through the observation of the characteristic SERRS spectrum of emeraldine salt at 1064nm.

摘要

采用表面增强共振拉曼散射（SERRS）技术，在3种不同的激发辐射下，研究了翡翠碱（聚苯胺 - EB）与银和金胶体的相互作用。由于SERRS技术具有极高的灵敏度，在银和金胶体悬浮液中，聚苯胺 - EB浓度的检测限约为2×10⁻⁷ mol L⁻¹。金属胶体的紫外 - 可见 - 近红外光谱随聚苯胺 - EB浓度的变化表明，金胶体比银胶体具有更高的聚集程度。聚苯胺 - EB在金属胶体上的SERRS光谱有助于研究主要在金属表面形成的聚合物种类。聚苯胺 - EB吸附在金属纳米颗粒上后形成的聚合物强烈依赖于金属胶体的性质。对于银胶体，聚苯胺 - EB被氧化为过苯胺黑，而通过观察1064nm处翡翠盐的特征SERRS光谱，证明了聚苯胺 - EB在金纳米颗粒上的掺杂过程。