Materials synthesis and how synthesis conditions affect a material’s microstructure and functional properties lie at the heart of the discipline of Materials Science & Engineering. A number of faculty at UC Davis (Mukherjee, Risbud, Castro) continue to be at the forefront of the use of fast sintering for the synthesis of new materials. UC Davis houses exclusive capabilities in pulsed electric current synthesis of nanocrystalline oxide ceramics. The first Spark Plasma Sintering (SPS) system in North America (Syntex SPS-825S) as well as an older sintering system (Syntex 1050) are housed in the CHMS Department. A specific focus of this research is to determine the fundamental atomic-scale mechanisms of electrical fields, currents, and heating rates in the consolidation of nanomaterials. In a collaborative effort, faculty combine in situ TEM techniques (van Benthem) with macroscopic field-assisted sintering procedures (Mukherjee) and calorimetry (Castro) to correlate microstructure evolution, processing parameters, and thermodynamic driving forces. Mukherjee and van Benthem collaborate on the evaluation of mechanical properties of nanogranular microstructures after SPS through in situ nanoindentation in TEM and SEM.
Another unique synthesis tool is a state-of-the-art pulsed laser deposition system (Takamura) which is ideally suited for the growth of thin films and heterostructures of ceramic oxide materials. A high energy electron diffraction system permits the in situ characterization of the growth process to determine the growth modes and to control the thickness of the layers with unit cell precision, permitting the synthesis of artificial layered materials not available in bulk form. The Mahajan group, on the other hand, utilizes metal organic chemical vapor deposition (MOCVD) to grow epitaxial quantum wells in III-V semiconductors. The Moule group works on solution processing of organic semiconductor materials and recently developed a polymer patterning technique called dopant induced solubility control (DISC). Using this method we can solution pattern polymers with diffraction limited resolution to produce any image in the polymer without damaging it.