Date: Thursday, May 9th
Presenter: Xiulei (David) Ji, Department of Chemistry, Oregon State University
I will talk about projects on scalable nanomanufacturing in our materials electrochemistry lab. The first is about the fabrication of highly nanoporous silicon-based materials. By employing table salt (NaCl) as a heat scavenger for the magnesiothermic reduction reactions (MRR), we developed an efficient and scalable route to convert SiO2-based materials into nanoporous Si composites. Fusion of NaCl during the reaction consumes a large amount of heat that otherwise collapses the nano-porosity of products and agglomerates silicon domains into large crystals. Secondly, I will introduce our new ambient atomic-layer coating method based on hydrolysis. Porous materials are strategically important in applications of energy, separation, and sensors. There are only limited compositions that could be prepared into porous structures economically, e.g. carbon and silica. The intrinsic properties of porous substrates cannot provide the needed functionality in many scenarios. It is therefore highly desirable to enable non-intrinsic properties for porous materials by coating their surface with a very thin layer while maintaining their architectural features. Ideally, the coating is conformal, continuous and of controllable thickness substantially smaller than the pore size of porous structures. Lastly, I will also briefly mention our projects on sodium-ion batteries and high-power capacitors.