title: A Snapshot of the Properties of Single Nanoparticles at the Moment of a Collision.
abstract: Direct electrochemical characterization of freely moving nanoparticles (NPs) at the individual particle level is challenging. A method is presented that can achieve this goal based on the collision between a NP and an ultramicroelectrode (UME). By applying a sinusoidal potential to the UME and monitoring the current response in the frequency domain, a sudden change in the phase angle indicates the arrival of a NP at the UME. The response induced by the collision can be isolated and used to explore the properties of the NP. This method, analogous to a high-speed camera, can obtain a snapshot of the properties of the single NP at the moment of a collision. The proposed method was employed to investigate the properties of both the hard catalytic Pt NP and soft electroactive emulsion droplets, and many new insights were revealed thereafter. The method also has the potential to be applied in many other fields, where the interested signals appear as discrete events.
authors.affiliation: School of Chemistry and Chemical Engineering, South China University of Technology, Wushan Road, Guangzhou, P. R. China.
authors.forename: Xinjian
authors.initials: X
authors.lastname: Huang
authors.affiliation: School of Chemistry and Chemical Engineering, South China University of Technology, Wushan Road, Guangzhou, P. R. China.
authors.forename: Haiqiang
authors.initials: H
authors.lastname: Deng
authors.affiliation: School of Chemistry and Chemical Engineering, South China University of Technology, Wushan Road, Guangzhou, P. R. China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Liu
authors.affiliation: School of Chemistry and Chemical Engineering, South China University of Technology, Wushan Road, Guangzhou, P. R. China.
authors.forename: Jing
authors.initials: J
authors.lastname: Jiang
authors.affiliation: School of Chemistry and Chemical Engineering, South China University of Technology, Wushan Road, Guangzhou, P. R. China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zeng
authors.affiliation: School of Chemistry and Chemical Engineering, South China University of Technology, Wushan Road, Guangzhou, P. R. China. wanglsh@scut.edu.cn.
authors.forename: Lishi
authors.initials: L
authors.lastname: Wang
keywords: collisions; electrochemistry; emulsions; nanoparticles; phase angles