Contamination-Free Transmission Electron Microscopy for High-Resolution Carbon Elemental Mapping of Polymers

Specimen contamination induced by electron beam irradiation has long been a serious problem for high-resolution imaging and analysis by a transmission electron microscope (TEM). It creates a deposition of carbonaceous compounds on a region under study, causing the loss of resolution. We developed a method to reduce the beam-induced specimen contamination by cleaning a TEM with activated oxygen radicals. The hydrocarbon contaminants accumulated inside the microscope’s chamber can be etched away by gentle chemical oxidation without causing any damage to the microscope. The “contamination-free TEM” can effectively suppress the deposition of carbon-rich products on a specimen and therefore enables us to perform high-resolution carbon elemental mapping by energy-filtering transmission electron microscopy (EFTEM). In this study, we investigated the structure of polymer brushes immobilized on a silica nanoparticle (SiNP), of which molecular weight, length, and density of the brushes had been characterized in det...