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Kaur, Sandeep

Publications and source records attributed to Kaur, Sandeep.

5 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Emerging Rare Earth Element Separation Technologies

Rare earth elements are essential for numerous clean energy applications, yet their mining, separation, and processing pose significant environmental challenges. Traditional separation processes often result in ecological damage, highlighting the critical need for innovative techniques that reduce environmental impacts. This article reviews recent advancements in rare earth separation technologies, with a particular focus on the role of neutral organic compounds. It explores how these compounds change selectivity across the rare earth series, offering promising strategies for designing more effective rare earth element separation systems. Furthermore, the article points out research areas requiring additional investigation to improve the sustainability of these critical processes.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Hydrophilic and hydrophobic carboxamide pincers as anion hosts

Hydrophobic and hydrophilic, monotopic and ditopic carboxamide pincer hosts containing ethyl, hexyl, 2-hydroxyethyl and 2-hydroxyethyl ethyl ether pendant arms were synthesized. Solubility trends indicated that solubilities in water or hydrocarbon solvents varied depending on the nature of the pendant arms. Binding constants for hydrophilic pincers were larger in general than their hydrophobic analogs. Furthermore, significant synergistic binding effects for the ditopic hosts were not observed.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2016

Interaction between fullerene halves C{sub n} (n ≤ 40) and single wall carbon nanotube

We have investigated the structural and electronic properties of carbon nanotube with small fullerene halves C{sub n} (n ≤ 40) which are covalently bonded to the side wall of an armchair single wall carbon nanotube (SWCNT) using first principle method based on density functional theory. The fullerene size results in weak bonding between fullerene halves and carbon nanotube (CNT). Further, it was found that the C-C bond distance that attaches the fullerene half and CNT is of the order of 1.60 Å. The calculated binding energies indicate the stability of the complexes formed. The HOMO-LUMO gaps and electron density of state plots points towards the metallicity of the complex formed. Our calculations on charge transfer reveal that very small amount of charge is transferred from CNT to fullerene halves.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2016

DFT study of small fullerene dimer complexes C{sub 20}-N{sub m}@C{sub n} (m = 1-6 and n = 24, 28, 32, 36 and 40)

First principle calculations based on density functional theory were performed to calculate the structural and electronic properties of C{sub 20}-N{sub m}@C{sub n} dimer complexes. The calculated binding energies of the complexes formed are comparable to C{sub 60} dimer which ensures their stability. The bond lengths of these dimer complexes were found to be nearly same as pure complexes C{sub 20}-C{sub n}. Further, nitrogen (N) atoms were encapsulated inside the secondary cage (C{sub n}) of dimer complexes and the number of N atoms depends on diameter of the cage. The HOMO-LUMO gaps of new proposed complexes indicate the increase in gap as compared to pure complexes. Mulliken charge analysis of these complexes has been studied which shows the significant charge transfer from the N atoms to the secondary cage of these complexes. The study propose the formation of the new dimer complexes which are stable and are able to encapsulate atoms which are otherwise reactive in free space.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗