Electrochemistry at a single nanoparticle: from bipolar regime to tunnelling,Faraday Discussions

当前位置： X-MOL 学术 › Faraday Discuss. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Electrochemistry at a single nanoparticle: from bipolar regime to tunnelling
Faraday Discussions ( IF 3.3 ) Pub Date : 2018-07-06 , DOI: 10.1039/c8fd00041g
Tong Sun _{1,

2,

3,

4,

5} , Dengchao Wang _{1,

2,

3,

4} , Michael V. Mirkin _{1,

2,

3,

4,

5}

Affiliation

This paper is concerned with long-distance interactions between an unbiased metal nanoparticle (NP) and a nanoelectrode employed as a tip in the scanning electrochemical microscope (SECM). A NP immobilized on the inert substrate acts as a bipolar electrode, producing positive SECM feedback. The tip current magnitude depends strongly on the ratio of the particle and tip radii and the heterogeneous charge-transfer kinetics. The onset of electron tunneling was observed at very short separation distances (<2–3 nm) at which the NP behaves as a part of the tip electrode. The rate constant of the electron-transfer (ET) or electrocatalytic reaction at the NP can be extracted from either feedback or tunneling current. The tunneling mode of SECM can be used to investigate heterogeneous reactions occurring at a single NP without making an ohmic contact with it. This technique can also help elucidate nanoparticle/electrode interactions in various electrochemical systems ranging from NPs immobilized on the electrode surface to nanoimpact collision events.

中文翻译：

单个纳米粒子上的电化学：从双极态到隧穿

本文关注的是无偏金属纳米粒子（NP）和用作扫描电化学显微镜（SECM）尖端的纳米电极之间的长距离相互作用。固定在惰性基材上的NP充当双极电极，产生正的SECM反馈。尖端电流的大小在很大程度上取决于粒子与尖端半径的比率以及异质电荷转移动力学。在非常短的分离距离（<2-3 nm）处观察到电子隧穿的开始，在该距离处NP表现为尖端电极的一部分。NP处的电子转移（ET）或电催化反应的速率常数可以从反馈或隧穿电流中提取。SECM的隧穿模式可用于研究在单个NP上发生的异质反应，而无需与之发生欧姆接触。这项技术还可以帮助阐明各种电化学系统中的纳米粒子/电极相互作用，从固定在电极表面的NP到纳米撞击碰撞事件，不一而足。

更新日期：2018-10-10

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11