Acquisition of a High-Resolution, Point-Focusing Small-Angle X-Ray Scattering System for Nanostructured Materials Research and Education

Princeton University, Princeton NJ

Investigators

Abstract

This award from the Instrumentation for Materials Research program funds a major enhancement of the capabilities for small-angle x-ray scattering (SAXS) located at Princeton University. The award permits the acquisition of a point-focusing SAXS instrument, which will be shared principally amongst users at Princeton and the New Jersey Institute of Technology (NJIT). This instrument uses double-focusing mirror/monochromator optics to focus a substantial solid angle of x-radiation to a small spot in the detector plane. This optical geometry provides access to the very small angles needed to characterize structures with size scales from 1-100 nm. SAXS also has the important advantage of being readily adapted for in-situ measurements; cells for operation at elevated temperature and a scanning calorimeter stage will be incorporated into the SAXS system. Since this instrument permits detailed characterization of anisotropic specimens with structure on the nanoscale, it will support a range of research avenues where controlling the orientation of nanostructural features is the aim. Projects at Princeton and NJIT which will this instrument will support are directed towards: guided self-assembly of mesoporous silicates through applied electric fields; templated crystallization in block copolymers; new nanostructured organic/inorganic composites for proton exchange membrane fuel cells; orientation of block copolymers and block copolymer/carbon nanotube composites; and structure-property-processing relationships in crystalline polymer fibers and crystallizable ionomers. The instrument will be used by researchers ranging from postdocs to undergraduates, from Princeton, NJIT, and elsewhere. Moreover, the modular nature of the SAXS system encourages the design of new sample stages and modification of existing modules, thus allowing students the opportunity to gain valuable experience in instrument design. %%% This award from the Instrumentation for Materials Research program funds a major enhancement of the capabilities for small-angle x-ray scattering (SAXS) located at Princeton University. SAXS is a powerful technique for characterizing nanostructured materials (size scales from 1-100 nm), and fully complements existing electron and scanning probe microscopy facilities at Princeton. The new SAXS instrument will be shared amongst users at Princeton and the New Jersey Institute of Technology (NJIT) and elsewhere in the study of organic, inorganic, and composite materials with applications as diverse as nanoporous filters, membranes for portable fuel cells, and biodegradable polymer fibers. The state-of-the-art instrument will be incorporated into a facility with two existing SAXS systems (of complementary, but more limited, capabilities). Users will include postdoctoral researchers, graduate students, and undergraduates, the last of these through both undergraduate research and by utilizing the instrument in an undergraduate materials science laboratory course.