Diluted exciplex concentration in organic light emitting diodes for blue-shifted spectra and improved efficiency

In this work, the effects of different ratios of donor/acceptor and spacer host materials on exciplex organic light emitting diodes (OLED) based DMAC-DPS:PO-T2T were explored, an obvious spectral blue-shift and...

Uniform Coverage of High-loading Sulfur on Cross-linked Carbon Nanofiber for High Reaction Kinetics in the Li-S Batteries with Low Electrolyte/Sulfur Ratio

The aggregation of high loading sulfur on host materials at low carbon/sulfur (C/S) ratio results in the limited S↔Li2S reaction kinetics and shuttle effect of polysulfide, which is the bottleneck...

Studying the Nonlinear Optical Properties of Fluoride Laser Host Materials in the Ultraviolet Wavelength Region

Fluoride host materials doped with trivalent cerium ions have previously been demonstrated as successful laser materials in the ultraviolet wavelength region. However, the nonlinear optical properties of the fluoride hosts in this wavelength region have not been investigated yet, although nonlinearity could result in undesirable effects such as self-focusing and pulse distortion when these fluoride materials are used as gain media in high-power, ultrashort pulse laser oscillator and amplifier systems. In this work, the nonlinear refractive index of lithium calcium aluminum fluoride (LiCaAlF6), lithium strontium aluminum fluoride (LiSrAlF6), lanthanum fluoride (LaF3), and yttrium lithium fluoride (YLiF4) fluoride host materials are determined using the Kramers–Krönig relation model in the ultraviolet wavelength region. Self-focusing conditions, particularly at the peak laser emission wavelength of these materials, are further analyzed. Results show that LiCaAlF6 has the smallest nonlinear refractive index and self-focusing, making it an ideal host material under the conditions of ultrashort pulse and ultrahigh-power laser generation.

On the Electrochemical Insertion of Mg2+in Na7V4(P2O7)4(PO4) and Na3V2(PO4)3 Host Materials

Next generation energy storage technologies need to be more sustainable and cheaper. Among Post-Li chemistries, Mg batteries are emerging as a possible alternative with desirable features like abundance of Mg on the Earth`s crust and a doubled volumetric capacity with respect to the current Li metal. However, research and development of Mg-batteries is still in its infancy stage and still many hurdles are to be understood and solved. For instance, cathode materials showing high capacities, operating at high potentials and with sufficient fast kinetics need to be designed and developed. Polyanionic materials are a class of sustainable and environmentally friendly materials that emerged as possible Mg2+ hosts. In this work the insertion of Mg cations inside the NASICON Na3V2(PO4)3 and, for the first time, in the mixed phosphate phase Na7V4(P2O7)4(PO4), is reported, structurally and electrochemically characterized.