Chemical and Biological Sciences Research Highlights

Discovery of stable nanodomains in an ionic liquid between 20 and 50˚C could enhance separations

Ionic liquids have exceptional properties in separations that may benefit the DOE mission in sequestering CO2 or rare earth elements. Understanding their structure provides a means of exploiting them. Previous investigations have focused on the small (~1-nm) domains formed by ionic liquids. We observe two large domains in tetradecyltrihexyl phosphonium chloride that are stable up to 50˚C.

Model for an arbitrary type of separation between two phases.

Extreme Confinement Stabilizes Undercoordinated Sites

Scientists at Ames National Laboratory discovered that confinement effects can be sufficient to reduce the effective coordination number of a metal in grafted organometallic complexes. They applied nuclear dipolar coupling measurements to study the temperature-dependent motions of rare earth amidinate complexes grafted to silica support materials. They observed that ligand dynamics could be hindered, and slowed down, in narrow-pore environments.

increased motions under extreme confinement

Theoretical framework for modeling of intermixing in core-shell nanocrystals (NCs) with realistic kinetics

Solution-phase synthesis of metallic nanocrystals (NCs) can produce NCs with tailored non-equilibrium shapes, and e.g., core-shell compositional profiles for bimetallic NCs. These structures can be tailored to optimize properties for applications such as catalysis, but they are metastable and possible post-synthesis evolution would degrade properties.

Understanding Rare Earth Element Adsorption

Theoretical exploration of solvation phenomena of bare rare-earth (RE) cations in room-temperature ionic-liquid (RTIL) to visualize the solvation mechanism of RE cations in RTIL at the molecular level.

Batch Scale Production of 3D Printed Extraction Sorbents

A cost-effective modification to a desktop resin 3D printer was demonstrated to produce polymeric ionic liquid (PIL) extraction devices.

Mechanistic Understanding of Rare-earth Element (REE) Capture

MCM-22 synthesis with varying Si:Al ratios is a model aluminosilicate for ytterbium (Yb) capture and also serves as a synthetic clay mimic to obtain in-depth mechanistic understanding of the capture.

Structure of Active Sites in Silica-Alumina Revealed

Scientists show that the catalytic active sites in silica-alumina are bridging and mirror those found in zeolites

Reshaping of nanocrystals: Failure of classical nucleation theory

Development of an appropriate theory for the stochastic reshaping processes based on the exact mater equations for this process.

Determining the Distributions of Surface Sites in Motion

A method was established to study the geometry and arrangement of dynamic surface species.

Sensitive NMR Method Reveals Motions of Surface Sites

A new, high-sensitivity, approach for studying molecular dynamics is reported, enabling the study of surface sites.

Stylized 1H chemical shift anisotropy measurements