ABSTRACT
The dynamic photoluminescence properties, and potential quenching mechanisms, of anti-B18H22, 4,4'-Br2-anti-B18H20, and 4,4'-I2-anti-B18H20 are investigated in solution and polymer films. UV stability studies of the neat powders show no decomposition occurring after intense 7 day light soaking. In contrast, clusters incorporated into polymer films are found to degrade into smaller borane fragments under the same irradiation conditions. To highlight the utility of these compounds, we leverage their favorable optical properties in a prototype UV imaging setup.
ABSTRACT
Electrochemical systems offer a versatile means for creating adaptive devices. However, the utility of electrochemical deposition is inherently limited by the properties of the electrolyte. The development of ionic liquids enables electrodeposition in high-vacuum environments and presents opportunities for creating electrochemically adaptive and regenerative spacecraft components. In this work, we developed a silver-rich, boron cluster ionic liquid (BCIL) for reversible electrodeposition of silver films. This air and moisture stable electrolyte was used to deposit metallic films in an electrochemical cell to tune the emissivity of the cell in situ, demonstrating a proof-of-concept design for spacecraft thermal control.
ABSTRACT
We report on the successful preparation and characterization of fluorescent magnetic core∕shell Fe(3)O(4)∕ZnSe nanoparticles (NPs) with a spherical shape by organometallic synthesis. The 7 nm core∕3 nm shell NPs show good magnetic and photoluminescence (PL) responses. The observed PL emission∕excitation spectra are shifted to shorter wavelengths, compared to a reference ZnSe NP sample. A dramatic reduction of PL quantum yield is also observed. The temperature dependence of the magnetization for the core∕shell NPs shows the characteristic features of two coexisting and interacting magnetic (Fe(3)O(4)) and nonmagnetic (ZnSe) phases. Compared to a reference Fe(3)O(4) NP sample, the room-temperature Néel relaxation time in core∕shell NPs is three times longer.
