Electrostatic potential measurement at the Pt/TiO$_2$ interface using electron holography

TL;DR

This study uses electron holography to measure the electrostatic potential at the Pt/TiO$_2$ interface, revealing charge transfer and potential differences crucial for device and catalytic applications.

Contribution

It demonstrates the application of electron holography to directly visualize electrostatic potential distribution at a metal/oxide interface, providing new insights into interfacial charge transfer.

Findings

Electrostatic potential decreases near TiO$_2$ at the interface.

Charge transfer occurs from TiO$_2$ to Pt.

Potential difference aligns with work function disparities.

Abstract

The interface of Pt/TiO$_2$ plays an essential role in device engineering and chemical reactions. Here, we report the electrostatic potential distribution of a Pt/TiO$_2$ interface by electron holography. The decrease of the electrostatic potential exists at TiO$_2$ in the vicinity of the interface, indicating the presence of negative charge due to electron transfer from TiO$_2$ and Pt. The decrease of the electrostatic potential can be understood in the difference in work functions between Pt and TiO$_2$. This study reveals the interplay between Pt and TiO$_2$ and the usefulness of electron holography for probing the potential in nanoscale interfaces.