In Situ Observation of Rh-CaTiO3 Catalysts during Reduction and Oxidation Treatments by Transmission Electron Microscopy

Sheng Dai, Shuyi Zhang, Michael B. Katz, George W. Graham, and Xiaoqing Pan, 2017
Rh-CaTiO3 catalyst reduced and oxidized via in situ TEM
Image courtesy of ACS Catalysis

Abstract

Scanning transmission electron microscopy of high-surface-area Rh-doped CaTiO3 powder, conducted near atmospheric pressure at elevated temperature (250–700 °C) by means of an electron-transparent gas cell with a sample heater, provides evidence for both cyclical precipitation–dissolution of Rh nanoparticles in response to redox cycling of the ambient gas and sintering of the powder.

Impact Statement

In situ oxidation and reduction experiments at 1 atm pressure revealed working mechanisms of intelligent catalyst nanoparticles.