Department of Chemistry, University of Adelaide, Adelaide, South Australia 5005, Australia.
Langmuir. 2010 Dec 7;26(23):17785-9. doi: 10.1021/la103063p. Epub 2010 Nov 11.
We present strong evidence for the oxidation of conjugated polymers in the formation of conjugated polymer dots (CPdots) using Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Although recent studies show that folding of the polymer chain into a compact 3D structure is involved in the formation of these nanoparticles, the process by which these intrinsically hydrophobic nanoscale particles circumvent aggregation in water is still not well understood. Zeta potential results show that these dots have a negatively charged surface at neutral pH, with a zeta potential and surface charge density of approximately -40 mV and (1.39 - 1.70) × 10(-2) C/m(2), respectively. In addition, quantitative elemental analysis of CPdots indicates that oxygen composes 7-13% of these nanoparticles. The overall results support the presence of chemical defects in forming a hydrophilic surface of CPdots. As a consequence, the charged surface contributes to inhibiting the aggregation of CPdots in water, leading to colloidal stability.
我们利用傅里叶变换红外光谱和 X 射线光电子能谱，提供了关于共轭聚合物在形成共轭聚合物点（CPdots）过程中发生氧化的有力证据。尽管最近的研究表明，聚合物链折叠成紧凑的 3D 结构与这些纳米粒子的形成有关，但这些内在疏水性纳米级粒子在水中避免聚集的过程仍未得到很好的理解。Zeta 电位结果表明，这些点在中性 pH 值下具有带负电荷的表面，其 Zeta 电位和表面电荷密度分别约为-40 mV 和（1.39-1.70）×10（-2）C/m（2）。此外，CPdots 的定量元素分析表明，氧组成了这些纳米粒子的 7-13%。总的研究结果支持在形成 CPdots 的亲水表面过程中存在化学缺陷。因此，带电荷的表面有助于抑制 CPdots 在水中的聚集，从而实现胶体稳定性。
