CAREER: Probing and Controlling the Magnetic Properties of Spinel Ferrite Nanoparticles through Crystal Chemistry

点击翻译按钮获取中文摘要

9875892 Zhang This goal of this project is to design and prepare nanol articles with specific magnetic properties, and to understand at the atomic level the factors determining potentially novel properties of magnetic nanoparticles, especially superparamagnetic properties. To achieve this understanding, an interdisciplinary approach that combines chemical synthesis, high-resolution electron microscopy characterization, neutron diffraction, Mossbauer spectroscopy and magnetic measurements will be used to systematically elucidate the relationships between magnetic properties, chemical composition and structure. Nanoparticles of spinel ferrites will be systematically studied. The crystal chemistry, such as the cation distribution and the oxidation states nanoparticles of various sizes will be studied, and the relationship to magnetic properties, such as the Curie temperature, magnetization hysteresis, superparamagnetic relaxation will be systematically investigated. Using nanoparticles with well-defined crystal chemistry, relationships between particle size and magnetic properties will be unambiguously determined. SQUID magnetometry, neutron diffraction, electron energy loss spectroscopy, and Mossbauer spectroscopy will be used in these studies of crystal chemistry and magnetic properties. We will systematically study the effect of magnetic couplings on the superparamagnetic properties of these spinel ferrite nanoparticles. Being an excellent teacher is a major part of a successful career in academia. This includes vigorously enhancing teaching skills through participating in faculty teaching enhancement programs and in activities for the innovation of classroom teaching. The proposed research project will be well integrated with teaching activities including developing experiments for the undergraduate teaching laboratory and broadly training students in research.%%%These proposed studies will have a significant impact on applications of magnetic nano-scale materials such as superparamagnetic nanoparticles. Understanding and controlling the superparamagnetic properties of nanoparticles is of great interest in information technology as it relates to the thermal stability of magnetic data bits for high density information storage. It is also crucial in biomedical applications such as contrast agents for magnetic resonance imaging (MRI) and magnetic carriers for magnetically guided drug delivery.