Optimized MEMS-based Nanoreactor for In-Situ Transmission Electron Microscopy Studies at High Temperature and Atmospheric Pressure

Abstract

Transmission electron microscopy is a powerful and commonly used tool to study nanoparticles, nanowires and 2D materials. It provides static information from the sample with atomic resolution, in high vacuum and at ambient temperature. However, in real processes, the environment is often different and dynamic.

MEMS-based sample carriers became a breakthrough for in-situ TEM where they function as a micro-sized laboratory and enable dynamic studies. The Nanoreactor allows for manipulation of samples by simultaneously applying heat and gas stimuli, through which real-time studies of solid-gas interactions are enabled inside the TEM. Many challenges are still to be faced in further optimization of Nanoreactors. Especially because the tiny scale and the extreme conditions at which these devices must operate, limit the number of suitable tools to characterize and help understand their behavior.

In this project, the electro-thermo-mechanical behavior of the Nanoreactor is characterized using various microscale analytical techniques. The obtained results are used to model the Nanoreactor with finite element analysis, including electric current, mechanical stability, heat transfer, gas flow, and their interdependence. Using the acquired knowledge and the model, an optimized Nanoreactor design is proposed that improves membrane deflection, spatial sample drift, temperature homogeneity, temperature stability, gas flow speed and gas switching time.