ORCA
Online Research @ Cardiff

Clear Cookie - decide language by browser settings

Probing composition distributions in nanoalloy catalysts with correlative electron microscopy

Liu, Shikai, Gow, Isla, Davies, Thomas, Barnes, Alexandra, Meenakshisundaram, Sankar

, Gong, Xiaoxiao, Howe, Alexander G. R., Dixon, Michael, Hutchings, Graham J.

, Kiely, Christopher J.

and He, Qian 2020. Probing composition distributions in nanoalloy catalysts with correlative electron microscopy. Journal of Materials Chemistry A 8 , pp. 15725-15733. 10.1039/D0TA00334D

Preview	PDF - Accepted Post-Print Version Download (635kB) \| Preview
Preview	PDF - Supplemental Material Download (1MB) \| Preview

Official URL: http://dx.doi.org/10.1039/D0TA00334D

Abstract

Alloyed nanoparticles are important functional materials and have wide applications especially in heterogeneous catalysis and electrocatalysis. Controlled synthesis of nanoalloys is desirable in order to understand their structure–property relationships and further optimize their performance. While many synthesis methods have been developed, information on the resultant composition distributions among particles is often not available, and uniformity of composition from particle-to-particle is often incorrectly assumed. Such an analysis would require extensive work on a high-resolution analytical electron microscope, which has some drawbacks and the high-resolution equipment is not always readily accessible. We hereby introduce an alternative way for composition analysis of nanoalloys via a correlative electron microscopy approach, separating the size measurement (imaging) and composition analysis between TEM and SEM instruments. Using a case study of two AuPd nanoalloys which have very similar size distributions but significantly different composition distributions and catalytic activities, we demonstrate both the necessity of performing composition distribution analysis on ultrasmall nanoalloys and the feasibility of this method. We show that a more efficient X-ray analysis on nanoalloys can be done in an SEM due to intrinsically higher ionization cross-sections from the relatively lower energy (e.g. 20 keV) electron beam and the possibility of using large probe currents and X-ray detectors with large collection angles.

Item Type:	Article
Date Type:	Published Online
Status:	Published
Schools:	Chemistry Cardiff Catalysis Institute (CCI)
Publisher:	Royal Society of Chemistry
ISSN:	2050-7488
Date of First Compliant Deposit:	13 March 2020
Date of Acceptance:	3 March 2020
Last Modified:	14 Nov 2024 08:45
URI:	https://orca.cardiff.ac.uk/id/eprint/130404