Operando analysis of a solid oxide fuel cell by environmental transmission electron microscopy

TL;DR

This study uses operando environmental transmission electron microscopy to directly observe microstructural changes in a solid oxide fuel cell under operating conditions, linking structure, environment, and performance at atomic resolution.

Contribution

It demonstrates a novel approach to correlate microstructure and performance in SOFCs using operando microscopy with microelectromechanical systems.

Findings

Microstructural evolution correlates with cell voltage and environmental conditions.

Anode oxidation state significantly impacts electrical properties.

Atomic-scale insights into material behavior during operation.

Abstract

Correlating the microstructure of an energy conversion device to its performance is often a complex exercise, notably in solid oxide fuel cell (SOFC) research. SOFCs combine multiple materials and interfaces that evolve in time due to high operating temperatures and reactive atmospheres. We demonstrate here that operando environmental transmission electron microscopy can simplify the identification of structure-property links in such systems. By contacting a cathode-electrolyte-anode cell to a heating and biasing microelectromechanical system in a single-chamber configuration, a direct correlation is found between the environmental conditions (O2 and H2 partial pressures, temperature), the cell voltage, and the microstructural evolution of the fuel cell, down to the atomic scale. The results shed new insights into the impact of the anode oxidation state and its morphology on the cell electrical properties.