B12-P-14Direct observation of concentration-dependent growth and dissolution of silver nanoparticles using in-situ liquid transmission electron microscopy

Abstract

Recently, much interest has been increased to develop in-situ TEM technique using various TEM holders. These techniques allow us to measure various materials properties while observing microstructure at high magnification. There is category of in-situ TEM that allows us to control the environment also called environmental transmission electron microscopy (E-TEM). E-TEM is a powerful technique to observe gas-solid or liquid-solid reactions in real time. In this study, we fabricated a window type environmental cell TEM holder and applied it to in-situ observation of decomposition of ZnO nanoparticles. The environmental cell TEM holder uses two silicon nitride membrane window TEM grids that are commercially available from Ted-Pella Inc.[1]. These windows should be thin enough to be electron transparent and thick enough to withstand pressure difference between inside and outside of the cell. The window grids were placed in a custom-made TEM holder between top and bottom o-ring that seal vacuum from column. By using custom made TEM holder, decomposition of ZnO nanoparticle have been observed. A JEOL 3010 TEM was used for the observation, which operated at 300kV electron acceleration voltage. ZnO nanoparticles mixed with DI water are decomposed under high-keV electron beam irradiation. ZnO nanoparticles are decomposed quite rapidly regardless of size of them when focused electron beam was irradiated. This observation allows a discussion of electron beam irradiation effect on the ZnO nanoparticles with DI water.