Nanoparticle-Induced Charge Redistribution of the Air鈥揥ater Interface
详细信息 查看全文
- 作者：Amaia Beloqui Redondo ; Inga Jordan ; Ibrahim Ziazadeh ; Armin Kleibert ; Javier B. Giorgi ; Hans Jakob W枚rner ; Sylvio May ; Zareen Abbas ; Matthew A. Brown
- 刊名：Journal of Physical Chemistry C
- 出版年：2015
- 出版时间：February 5, 2015
- 年：2015
- 卷：119
- 期：5
- 页码：2661-2668
- 全文大小：383K
- ISSN：1932-7455
文摘
The air鈥搘ater interface is believed to carry a negative electrostatic potential that is nontrivial to invert through pH, electrolyte, or electrolyte strength. Here, through a combined experimental and theoretical study, we show that the close approach of a negatively charged nanoparticle induces a charge redistribution of the air鈥搘ater interface. Using different electrolytes to control the interfacial potential of the nanoparticles, X-ray photoelectron spectroscopy (XPS) results establish that nanoparticles with a more negative zeta potential adsorb closer to the air鈥搘ater interface than do the same particles with a less negative zeta potential. The short-ranged attractive force between two (nominally) negative surfaces is caused by charge redistribution under the strong electric field of the nanoparticle that locally inverts the charge density of the air鈥搘ater interface from negative to positive. The nature of the nanoparticle鈥檚 counterions modulates the attractive interaction, which thus could be used to control reactivity, stability, and nanoparticle self-assembly at air鈥搘ater interfaces.