The development of nano-spinels represents a scalable approach for formation of earth abundant LED pumped phosphors that are soluble in organics for processing, have improved internal conversion efficiencies, and can achieve 200 Lm/W. The earth abundant spinel lattice not only reduces the cost of the host matrix, which accounts for > 90% of the material, but also provides chemical, thermal, and ionization stability while optimizing spectral performance. The improved performance is due to optimization of the distance from sensitizer to dopant to ensure efficient energy coupling between the singlet and triplet state of the molecular sensitizer and the Ln(III) levels through a Dexter energy transfer. In the packaged LED, the white light is produced by blending the line spectra of the lanthanide ion for blue (Ce), green (Tb, Er) and red (Eu, Sm). Nanoscale phosphors reduce material content, control type and density of defects, provide solvent soluble material, and a means to reduce lanthanide content.
The magnetic interactions that occur at the nanoscale allow for exotic phenomena to occur which have the ability to enhance the magnetic properties of a material above those observed in the bulk material. One such interaction that we are pursuing is exchange-spring behavior, which occurs when hard and soft magnetic materials are layered with one-another on the nanoscale (at or below the single domain size). This type of exchange-coupling is vital for the future of sustainable technologies, as it allows for the reduction of rare earth metals (Nd, Sm, and Dy -- which become increasingly more expensive every year) in the magnetic components of electric motors and turbines. Through use of the microwave reactor, we can control the size of both the core and shell of the materials, allowing for high tunability of the final magnetic properties.Back to Research