Title : Implications of Cerium Redox Additives on Gold Nanocrystal Transformations during Liquid Cell Electron Microscopy Experiments
The visualization of nanoscale processes in situ can advance our knowledge of chemical phenomena. Liquid cell transmission electron microscopy (LCTEM) is a technique that allows materials to be imaged within an encapsulated liquid to near-atomic resolution, enabling mechanistic insight into nanoscale transformations. Electrons used to form an image with LCTEM interact with liquids and these interactions alter the chemical environment of the system. In order to regulate this effect, Ce(III) is introduced to the system to scavenge highly reactive species and form a Ce(III)/Ce(IV) redox couple that controls electrochemical reactions. The ability to control the reactivity within LCTEM with chemical additives offers a viable route to precisely study chemical reaction dynamics in a liquid environment, such as noble metal dissolution. This presentation will report efforts to develop a complete model of the system’s chemical reaction network that integrates the possible reactions between water, gold, chloride, and the cerium redox additive. In addition, the model can predict experimental gold etching observables to support the validity of the proposed chemical reaction network. These efforts enable the development of predictive models that accurately simulate nanocrystal size transformations and chemical dynamics.