MRS Meetings and Events

 

EL06.08.01 2024 MRS Spring Meeting

Nanoscale Control of The Ionic Evolution within Complex Oxides

When and Where

Apr 25, 2024
1:30pm - 2:00pm

Room 343, Level 3, Summit

Presenter

Co-Author(s)

Pu Yu1

Tsinghua University1

Abstract

Pu Yu1

Tsinghua University1
Over the last decades, ionic evolution emerges as a powerful tuning knob to manipulate the material functionalities of complex oxides. In this talk, we will present a few new strategies to explore ionic evolution at the nanoscale, including the scanning probe tip-induced ionic evolution and electron beam illumination induced chemical reduction. For the tip-induced hydrogen evolution, the Pt-coated scanning probe serves as an efficient hydrogen catalyst, leading to a hydrogen spillover across the nano junction between the probe and sample surface. Furthermore, the application of positively-biased voltage through the junction drives protons into the sample, while negative voltage extracts protons out, giving rise to reversible proton evolution. Due to the associated electron filling, this method can then offer an exciting opportunity to harvest advanced functions such as insulator-metal transition through the tip-induced proton evolution. Furthermore, through the electron-beam illumination with a commercial scanning electron microscope, we also demonstrated locally controlled oxygen vacancy migration in the model system of VO<sub>2</sub>, and achieved a nano-scale structural transformation into V<sub>2</sub>O<sub>3</sub>. In this approach, the electron beam induces both surface oxygen desorption through radiolytic process and positively charged background through secondary electrons, which contribute cooperatively to facilitate the vacancy migration from the surface toward the sample bulk, leading to nanoscale chemical reduction through oxygen vacancy formation. We envision that these two approaches can be readily applied for other material systems, providing a promising strategy to manipulate and design novel functionalities in various materials.

Keywords

oxide

Symposium Organizers

Aiping Chen, Los Alamos National Laboratory
Woo Seok Choi, Sungkyunkwan University
Marta Gibert, Technische Universität Wien
Megan Holtz, Colorado School of Mines

Symposium Support

Silver
Korea Vacuum Tech, Ltd.

Bronze
Center for Integrated Nanotechnologies, Los Alamos National Laboratory
Radiant Technologies, Inc.

Publishing Alliance

MRS publishes with Springer Nature