| Nowadays people are relying on all kinds of electronic devices in their daily life. All these devices are getting smaller and lighter with longer battery life due to the improvement of nanotechnology and materials sciences. Electron microscopy (EM) plays a vital role in the evolution of materials characterization which shapes the technology in today's life. In electron microscopy, electron beam is used as the illumination source instead of visible light used in traditional optical microscopy, the wavelength of an electron is about 105 times shorter than visible light. By taking this advantage, the resolving power and magnification are greatly improved which gives us the ability to understand the morphology and the structure of smaller materials.;Besides high resolution and high magnifications, the electron-matter interactions in electron microscopy are also very interesting and provide useful information. Typically, there are three types of post electron-matter interaction electrons, and they are: secondary electrons, backscattered electrons and transmitted electrons. Different signals are carried out with these electron-matter interactions, the most common techniques including electron dispersive X-ray spectroscopy (EDS), electron energy loss spectroscopy (EELS) and selected area electron diffraction (SAED). In this dissertation, I will discuss how electron microscopy techniques approach complicated nanostructures, such as MnSb2Se4 nanorods to reveal the composition, structure, surfactant controlled size, and relative magnetic properties. Other important features such as mapping localized surface plasmon resonance (LSPR) using EELS and newly developed liquid cell scanning mode transmission electron microscopy (STEM) in situ observation are also presented. |
