Chemical and Biological Sciences Research Highlights

Organometallic Rare Earths in Zeolites Are Activated for Hydrocarbon Functionalization

Rare earth cations, traditionally used as structural stabilizers in petrochemical cracking catalysis, have been activated as organometallic sites for arene CH functionalization, establishing a foundation for commodity-scale conversions that conventionally require precious noble transition-metals.

C-H borylation catalyzed by La in HY30 faujasite

Superresolution Introduced to NMR Spectroscopy

Scientists have successfully applied superresolution microscopy methods to NMR spectroscopy, yielding dramatically higher resolution and detail.

Controlling the Selectivity of Rare Earth Elements (REE) on Micas

Researchers discover new fundamental knowledge about the role impurities found in natural ion adsorption minerals play in the interactions with REE, which provides deep insights into controlling REE separations by solid adsorbents.

Rare Earth Element (REE) Extraction with Ionic Liquid (IL)

While organic solvent extraction is a commonly employed technique for rare earth element (REE) recovery, it poses challenges associated with a high volatility, toxicity of solvent, and energy consumption. To address these issues, ionic liquids (ILs) have emerged as more environmentally friendly alternatives, offering low volatility and tunable properties to improve recovery processes. Reports have shown that adding extractants improves both the selectivity and affinity for rare earth element (REE) capture. However, the surrounding chemical environment of REEs in these systems remains not well understood.

Schematic representation of molecular interactions.

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.

Visualization of increased motions under extreme confinement from the breaking of support-metal interactions

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.