Laponite® synthetic clays, renowned for their versatility and ability to enhance optical properties, underwent a comprehensive examination via Small and Wide-Angle X-ray Scattering (SAXS/WAXS) to probe their intricate interaction dynamics with a cationic organic dye. The investigation delved into the multifaceted structure-property relationship, with a specific focus on optical characteristics. We hypothesize that particle-dye interactions play a pivotal role in suppressing non-radiative relaxation pathways, thereby influencing fluorescence lifetime and emission intensity. Through systematic manipulation of Laponite® concentration (0.5 wt.% and 2.0 wt.%), both with and without the dye, we discern significant morphological transformations. At 0.5 wt.% Laponite®, SAXS scattering curves exhibit distinct changes in the low-q region, suggesting alterations in the nanoparticle organization upon dye incorporation. WAXS analysis of 2.0 wt.% Laponite® gels unveils the influence of the dye on the interlayer interactions, with a notable enhancement in the sharpness of the (001) basal reflection. The elucidation of these phenomena offer valuable insights into the structural evolution of Laponite® nanoparticles upon interaction with organic dye molecules. The enhanced understanding of these interactions holds significant implications for the design and optimization of novel hybrid materials with tailored optical properties, paving the way for diverse applications in fields such as photonics, optoelectronics, and surface science.

Ion hydration is integral to biological functions, pharmaceutical applications, and future green-energy endeavors. Fluoride compounds in particular are known to react with water and play a major role in the stratospheric chemistry of chlorofluorocarbons. Classical molecular dynamics simulations have been able to predict numerous properties of fluoride hydration. However, classical molecular dynamics omits nuclear quantum effects arising from the presence of light hydrogen nuclei in water. Furthermore, since fluoride forms hydrogen bonds in water, it weakens the covalent OH bonds, and can lead to an enhancement in nuclear quantum effects. Thus, a complete understanding of fluoride hydration necessitates the system be treated quantum-mechanically. In this study, we employ path-integral based quantum dynamical methods along with the q-TIP4P/f and Madrid-2019 potential energy surfaces, for water and fluoride respectively, to study the role of nuclear quantum effects in fluoride hydration. We will discuss radial distribution functions, diffusion coefficients, mean residence times, and infrared spectra as a function of solvation shells to explain the hydration structure of water around fluoride.

Per- and polyfluoroalkyl substances (PFAS) are highly persistent chemicals known for their resistance to heat and degradation. This persistence is due to their strong carbon-fluorine bonds, which are also symmetrically arranged, making them hydrophobic. Many PFAS are negatively ionized at environmental pH due to their hydrophilic moiety. PFAS are found to bioaccumulate in humans, leading to health risks such as cancer and reduced immune system function, among others. Despite their numerous health effects PFAS are commonly used in food packaging, non-stick cookware, firefighting foams, etc, resulting in daily human exposure. In this research three sorbents particles with cationic properties are evaluated for their efficiency in extracting 15 anionic PFAS with alkyl chain length from C4 to C14. The sorbents are based on silica functionalized with C18, PCS (Positively Charged Sorbent) C18 and phenyl-hexyl PCS, and have a diameter of 2.7 µm. These functional groups can establish different interactions with PFAS through their hydrophobic tail and hydrophilic heads. Electrostatic interactions are the main drivers of the extraction process.The method utilized for extraction is called solid phase microextraction (SPME), a preconcentration technique which allows the separation of PFAS from complex environmental samples and biofluids. After extraction, chromatographic separation and detection is performed with liquid chromatography tandem mass spectrometry. Our aim is to develop an efficient extraction method for both long and shorter chain PFAS, since environmental samples are often contaminated with mixtures of PFAS and it is necessary to simultaneously extract them with one quick, fast and environmentally friendly method.

Tropospheric ozone and its negative effects account for one million premature deaths every year. Biomass burning has been an increasingly prevalent problem that has contributed to creating tropospheric ozone due to ongoing climate change. Climate change has exacerbated various aspects of wildfires such as their intensity, duration, and frequency. Wildfires release various pollutants including volatile organic compounds (VOCs) and nitrogen oxides (NOx) that create ozone through chemical reactions that include heat and sunlight. Thus, due to the increase in wildfires, the creation of ozone has been an ongoing concern specifically due to its negative effects on human health and the environment. In 2020 California and Colorado wildfires as well as 2023 Canadian wildfires dispersed smoke causing elevated ozone levels in various areas. The summer of 2020 saw numerous elevated ozone days for Colorado, particularly between the end of August and early September due to the Pine Gulch, Grizzly Creek, and Cameron Peak fires. California saw particularly high ozone during the same dates due to the August Complex, SCU Lighting Complex, LNU Lightning Complex, and North Complex fires. In 2023 Canadian wildfires impacted ozone levels across the US particularly during early June in various places across Virginia due to the Donnie Creek Fire. Using surface ozone levels from monitoring sites and ozone data from ozonesonde launches, high tropospheric ozone concentrations were found to impact AQI. Furthermore, using HY-SPLIT back trajectories, tracking the location of elevated ozone levels were found to come from blazing wildfires. Preliminary findings have shown wildfire smoke plumes contributing to elevated tropospheric ozone levels.