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  • Correlating Photo-Induced Changes in Surface Charge and Electronic Conductivity in Oxide Nanoparticles with In Situ Electron Microscopy

This content will become publicly available on June 3, 2026

Title: Correlating Photo-Induced Changes in Surface Charge and Electronic Conductivity in Oxide Nanoparticles with In Situ Electron Microscopy
Photon induced changes in charge distributions and conductivities of oxide nanoparticles (rhodium doped strontium titanate) have been determined using in situ electron holography. The holography-based approach relies on the application of two distinct stimuli to the material of interest: electrons and photons. The high energy electron beam stimulates the formation of a layer of positive surface charge due to secondary electron emission. Light illumination reduces this charge due to enhanced electronic conductivity arising from photo-electron excitation. For moderate photon and electron illumination rates, there is a simple linear relationship between the steady state surface charge and the sample conductivity. For rhodium doped strontium titanate, we observe a factor of 3 increase in the conductivity for the illumination conditions employed here. The approach is general and can be employed to measure photo-induced changes in other semiconducting systems.  more » « less
Award ID(s):
2109202 1840841
PAR ID:
10610846
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
ACS Nano
Volume:
19
Issue:
21
ISSN:
1936-0851
Page Range / eLocation ID:
19567 to 19577
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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