Nanocatalysts are key for the future of sustainable chemistry, yet, they typically suffer from rapid deactivation caused by a process called sintering. In a recent study led by the ALBA Synchrotron and Ghent University, researchers have developed an integrated approach where they complement the use of several characterization techniques to study platinum nanoparticle sintering at the micro-, meso- and macroscale. The demonstrated approach shows that mesoscale heterogeneities in the nanoparticle population drive sintering. This work will help broaden the fundamental understanding of nanoparticle sintering and thus design better strategies for catalyst fabrication.
Metal nanoparticle catalysts are the workhorses in a broad range of industrially important chemical processes such as producing clean fuels, chemicals and pharmaceuticals or cleaning exhaust from automobiles. These nanocatalysts are key for the future of sustainable chemistry, yet they typically suffer from rapid deactivation caused by a process called sintering. Due to sintering, the average nanoparticle size increases since this is energetically more efficient for the nanoparticles. However, this decreases their catalytic power.
To date, sintering phenomena are analyzed either at the macroscale, to examine averaged nanoparticle properties, or at the microscale, studying individual nanoparticles. However there is a knowledge gap on the nanocatalysts behavior at the mesoscale, the intermediate length scale between the macro and the micro worlds. At the mesoscale, large ensembles with thousands of nanoparticles can be studied as a “population” in which nanoparticles “communicate” – interact – with each other. In this context, nanoparticle sintering can be considered as a dynamic population of interacting nanoparticles, each of them trading and exchanging atoms to gain stability within the nanoparticle hierarchy.
In a recent study led by the ALBA Synchrotron and Ghent University, researchers have developed an integrated approach where they complement the use of several characterization techniques to study platinum nanoparticle sintering at the micro-, meso- and macroscale. More specifically, they used different analytical techniques and X-ray scattering characterization at the NCD-SWEET beamline in ALBA to show that mesoscale heterogeneities in the nanoparticle population drive sintering. Thus, deleting these heterogeneities would help to avoid sintering.
Read more on the ALBA website
Image: Researchers inside the experimental hutch of the NCD-SWEET beamline at the ALBA Synchrotron. From left to right: Zhiwei Zhang (Ghent University), Matthias Minjauw (Ghent University), Matthias Filez (Ghent University – KU Leuven) and Juan Santo Domingo Peñaranda (Ghent University).