Kelvin probe force microscopy study of a Pt/TiO2 catalyst model placed in an atmospheric pressure of N2 environment.

Ryohei Kokawa,Hiroshi Onishi,Masahiro Ohta,Akira Sasahara

doi:10.1002/asia.201101001

Abstract

A catalyst model comprising platinum nanoparticles deposited on a TiO2(110) wafer was prepared in a vacuum, transferred in air, and characterized with a Kelvin probe force microscope placed in a N2 environment. The topography and local work function of individual nanoparticles were observed with single-nanometer resolution in the N2 environment of one atmosphere pressure. Some nanoparticle presented positive shifts of work function relative to that of the TiO2 surface, while the others showed negative shifts. This finding suggests heterogeneous properties of the nanoparticles exposed to air and then N2. The ability of the advanced microscope was demonstrated in observing the work function of metal nanoparticles on a metal oxide support even in the presence of vapor environments.

Highlights

Our current civilization is supported by a number of chemical processes for artificial materials production
The topography was observed with the ordinary frequencymodulation atomic force microscopy (FM-AFM) in a N2 environment of one atmospheric pressure
The terrace width was 100 nm or more, and the step height was 0.3 nm. These features reproduced the topographic features of sputter-annealed TiO2ACHTUNGRE(110) wafers observed in vacuum.[ 40-42]. Nanometer-sized particles appeared on the terraces

Summary

Introduction

Our current civilization is supported by a number of chemical processes for artificial materials production. The ability of the advanced microscope was demonstrated in observing the work function of metal nanoparticles on a metal oxide support even in the presence of vapor environments.

Results

Conclusion