Surface modified copper foam with cobalt phthalocyanine carbon nanotube hybrids for tuning CO reduction reaction products.

The CO reduction reaction (CORR) is a feasible way to convert this greenhouse gas into molecules of industrial interest. Herein we present the modification of the Cu foam cathode using molecular catalyst hybrid from cobalt phthalocyanine (CoPc) to increase selectivity and stability towards CORR products in a flow cell setup.

Elucidating the Role of Electrochemically Formed LiF in Discharge and Aging of Li-CF Batteries.

Fifty years after its introduction, the lithium-carbon monofluoride (Li-CF) battery still has the highest cell-level specific energy demonstrated in a practical cell format. However, few studies have analyzed how the main electrochemical discharge product, LiF, evolves during the discharge and cell rest periods. To fill this gap in understanding, we investigated molecular-level and interfacial changes in CF electrodes upon the discharge and aging of Li-CF cells, revealing the role of LiF beyond that of a simple discharge product.

Fluoride in the SEI Stabilizes the Li Metal Interface in Li-S Batteries with Solvate Electrolytes.

Lithium-sulfur (Li-S) batteries offer high theoretical gravimetric capacities at low cost relative to commercial lithium-ion batteries. However, the solubility of intermediate polysulfides in conventional electrolytes leads to irreversible capacity fade the polysulfide shuttle effect. Highly concentrated solvate electrolytes reduce polysulfide solubility and improve the reductive stability of the electrolyte against Li metal anodes, but reactivity at the Li/solvate electrolyte interface has not been studied in detail.

Influence of Lithium Polysulfide Clustering on the Kinetics of Electrochemical Conversion in Lithium-Sulfur Batteries.

The electrochemistry of lithium-sulfur (Li-S) batteries is heavily reliant on the structure and dynamics of lithium polysulfides, which dissolve into the liquid electrolyte and mediate the electrochemical conversion process during operation. This behavior is considerably distinct from the widely used lithium-ion batteries, necessitating new mechanistic insights to fully understand the electrochemical phenomena. Testing at low-temperature conditions presents a unique opportunity to glean new insights into the chemistry in kinetically constrained environments.

Aluminum Precursor Interactions with Alkali Compounds in Thermal Atomic Layer Etching and Deposition Processes.

Surface fluorination and volatilization using hydrogen fluoride and trimethyaluminum (TMA) is a useful approach to the thermal atomic layer etching of AlO. We have previously shown that significant enhancement of the TMA etching effect occurs when performed in the presence of lithium fluoride chamber-conditioning films. Now, we extend this enhanced approach to other alkali halide compounds including NaCl, KBr, and CsI.

3D Printed Minerals as Astrobiology Analogs of Hydrothermal Vent Chimneys.

Hydrothermal vents, which are highly plausible habitable environments for life and of interest for some origin-of-life scenarios, may exist on icy moons such as Europa or Enceladus in addition to Earth. Some hydrothermal vent chimney structures are extremely porous and friable, making their reconstruction in the lab challenging ( brucite or saponite in alkaline hydrothermal settings). Here, we present the results from our efforts to reconstruct a simplified chimney structure directly out of mineral powder using binder jet additive manufacturing.

Geoelectrodes and Fuel Cells for Simulating Hydrothermal Vent Environments.

Gradients generated in hydrothermal systems provide a significant source of free energy for chemosynthetic life and may play a role in present-day habitability on ocean worlds. Electron/proton/ion gradients, particularly in the context of hydrothermal chimney structures, may also be relevant to the origins of life on Earth. Hydrothermal vents are similar in some ways to typical fuel cell devices: redox/pH gradients between seawater and hydrothermal fluid are analogous to the fuel cell oxidant and fuel reservoirs; the porous chimney wall is analogous to a separator or ion-exchange membrane and is also a conductive path for electrons; and the hydrothermal minerals are analogous to electrode catalysts.

In Situ Polysulfide Detection in Lithium Sulfur Cells.

Lithium sulfur batteries promise significant improvements in specific energy compared to Li-ion, but are limited by capacity fade upon cycling. Efforts to improve durability have focused on suppressing the solubility of intermediate polysulfides in the electrolyte. Here we describe an in situ electrochemical polysulfide detection method based on the cyclic volatmmetric response.

Preparation of fluorinated RNA nucleotide analogs potentially stable to enzymatic hydrolysis in RNA and DNA polymerase assays.

Analogs of ribonucleotides (RNA) stable to enzymatic hydrolysis were prepared and characterized. Computational investigations revealed that this class of compounds with a modified triphosphate exhibits the correct polarity and minimal steric effects compared to the natural molecule. Non-hydrolysable properties as well as the ability of the modified nucleotide to be recognized by enzymes were probed by performing single-turnover gap filling assays with T7 RNA polymerase and DNA polymerase β.

Lewis Acid Catalyzed Condensation-Cyclization Cascade: Direct Synthesis of Di/Trifluoromethyl-1,2,3,4-tetrahydroquinazolines.

Condensed heterocycles such as quinazolines constitute the framework of many promising drugs. The great impact of the dramatic fluorine effect in pharmaceuticals prompted a great surge in the quest for fluorinated drug design resulting in over 20 % fluorine-containing drugs in the market today. Therefore, finding an efficient and cost-effective method for the direct synthesis of fluorine-tagged quinazoline systems is of great significance in the pharmaceutical arena.

Amine-free reversible hydrogen storage in formate salts catalyzed by ruthenium pincer complex without pH control or solvent change.

Due to the intermittent nature of most renewable energy sources, such as solar and wind, energy storage is increasingly required. Since electricity is difficult to store, hydrogen obtained by electrochemical water splitting has been proposed as an energy carrier. However, the handling and transportation of hydrogen in large quantities is in itself a challenge.

Recycling of carbon dioxide to methanol and derived products - closing the loop.

Starting with coal, followed by petroleum oil and natural gas, the utilization of fossil fuels has allowed the fast and unprecedented development of human society. However, the burning of these resources in ever increasing pace is accompanied by large amounts of anthropogenic CO2 emissions, which are outpacing the natural carbon cycle, causing adverse global environmental changes, the full extent of which is still unclear. Even through fossil fuels are still abundant, they are nevertheless limited and will, in time, be depleted.

Increased perfusion of the femoral head in transient bone marrow edema syndrome.

The pathophysiology of transient bone marrow edema syndrome is not known. Ischemia has been suggested as the pathophysiologic factor, because the histologic findings are similar to those of early stage osteonecrosis. Angiographic studies of osteonecrotic femoral heads have shown arterial interruption and impaired perfusion.