Giant Radiolytic Dissolution Rates of Aqueous Ceria Observed in Situ by Liquid‐Cell TEM. Issue 10 (13th April 2017)

• Record Type: Journal Article
• Authors: Asghar, Muhammad Sajid Ali; Inkson, Beverley J.; Möbus, Günter
• Is Part Of: Chemphyschem. Volume 18:Issue 10(2017)
• Page Start: 1247
• Page End: 1251
• Publication Date: 2017-04-13
• Subjects: cerium oxide -- corrosion -- durability -- liquid-cell TEM -- radiolysis; Chemistry, Physical and theoretical -- Periodicals; 541.05
• DOI: 10.1002/cphc.201601398
• Languages: English
• ISSNs: 1439-4235

Abstract

Abstract: The dynamics of cerium oxide nanoparticle aqueous corrosion are revealed in situ. We use innovative liquid‐cell transmission electron microscopy (TEM) combined with deliberate high‐intensity electron‐beam irradiation of nanoparticle suspensions. This enables life video‐recording of materials reactions in liquid, with nm resolution. We introduce image quantification to measure detailed rates of dissolution as a function of time and particle size to be compared with literature data. Giant dissolution rates, exceeding any previous reports for chemical dissolution rates at room temperature by many orders of magnitude, are discovered. The reasons for this accelerated dissolution are outlined, including the importance of the radiolysis of water preceding the ceria attack. Electron–water interaction generates radicals, ions, and hydrated electrons, which assist in hydration and reductive dissolution of oxide minerals. The presented methodology has the potential to become a novel accelerated testing procedure to compare multiple nanoscale materials for relative aqueous durability. The ceria–water system is of crucial importance for the fields of catalysis, abrasive polishing, environmental remediation, and as simulant for actinide oxide behaviour in contact with liquid for nuclear engineering. Abstract : Cerium oxide nanoparticles are investigated in a liquid‐cell transmission electron microscopy specimen holder. Electron‐beam‐induced reactive water splitting products are found to first round and then dissolve the facetted particles at unprecedented dissolution rate.