In Situ Monitoring of Non-Thermal Plasma Cleaning of Surfactant Encapsulated Nanoparticles.

Autor: Li G; Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, USA., Zakharov DN; Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, USA., Sikder S; Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, USA.; Department of Materials Science and Chemical Engineering, Stony Brook University, Stony Brook, NY 11790, USA., Xu Y; Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, USA.; Department of Materials Science and Chemical Engineering, Stony Brook University, Stony Brook, NY 11790, USA., Tong X; Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, USA., Dimitrakellis P; Catalysis Center for Energy Innovation, Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19716, USA., Boscoboinik JA; Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, USA.
Jazyk: angličtina
Zdroj: Nanomaterials (Basel, Switzerland) [Nanomaterials (Basel)] 2024 Jan 31; Vol. 14 (3). Date of Electronic Publication: 2024 Jan 31.
DOI: 10.3390/nano14030290
Abstrakt: Surfactants are widely used in the synthesis of nanoparticles, as they have a remarkable ability to direct their growth to obtain well-defined shapes and sizes. However, their post-synthesis removal is a challenge, and the methods used often result in morphological changes that defeat the purpose of the initial controlled growth. Moreover, after the removal of surfactants, the highly active surfaces of nanomaterials may undergo structural reconstruction by exposure to a different environment. Thus, ex situ characterization after air exposure may not reflect the effect of the cleaning methods. Here, combining X-ray photoelectron spectroscopy, in situ infrared reflection absorption spectroscopy, and environmental transmission electron microscopy measurements with CO probe experiments, we investigated different surfactant-removal methods to produce clean metallic Pt nanoparticles from surfactant-encapsulated ones. It was demonstrated that both ultraviolet-ozone (UV-ozone) treatment and room temperature O 2 plasma treatment led to the formation of Pt oxides on the surface after the removal of the surfactant. On the other hand, when H 2 was used for plasma treatment, both the Pt 0 oxidation state and nanoparticle size distribution were preserved. In addition, H 2 plasma treatment can reduce Pt oxides after O 2 -based treatments, resulting in metallic nanoparticles with clean surfaces. These findings provide a better understanding of the various options for surfactant removal from metal nanoparticles and point toward non-thermal plasmas as the best route if the integrity of the nanoparticle needs to be preserved.
Databáze: MEDLINE