Several different preparation and morphologies of α-manganese oxide catalysts were synthesized, and their physical properties were characterized. These catalysts were also characterized by electrochemical means (RDV and CV) for oxygen reduction in both aqueous and organic electrolytes. The solvent-free preparation yielded catalysts with ideal physical properties: low average oxidation state (3.73) of manganese, small crystallite size (8.1 nm), small particle size (d = 10 nm, l = 30–100 nm), high surface area (144 m2 g–1), and pore volume (0.470 cm3/g). This catalyst displayed the highest activity in both aqueous (i L = 3.66 ± 0.12 mA cm–2, i 0 = 1.0 × 10–5 mA cm–2) and organic electrolytes (i L = 2.25 ± 0.15 mA cm–2, αn = 0.51). Doping the solvent-free preparation with Ni2+ slightly improved its oxygen reduction capabilities in aqueous (i L = 3.78 ± 0.15 mA cm–2, i 0 = 2.3 × 10–5 mA cm–2) and organic electrolytes (i L = 2.43 ± 0.17 mA cm–2, αn = 0.47). A large increase in the ability of the catalysts to decompose hydrogen peroxide was observed (2.7 ± 0.26 vs 0.53 ± 0.03 s–1 g–1), which is a good indicator of enhanced bifunctionality for application in secondary lithium air batteries. Stability tests in the presence of Li2O2 at elevated temperatures (100 °C) indicate a decrease in catalyst crystallinity as exposure time is increased.

A breath of fresh air: The octahedral molecular sieve (OMS‐2) catalyst shows outstanding catalytic activity, selectivity, and stability in the dehydrogenation of ethane into ethylene in the presence of CO2. This process can be extended for other alkanes, giving an ideal feedstock for any process involving alkene carbonylation, as a greenhouse gas, CO2, can be recycled.

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This investigation focused on the synthesis and characterization of a modified polyvinylsilazane (PVSZ) polymer. Previously, our group synthesized the PVSZ polymer through the ammonolysis of vinyltrichlorosilane (VTS) in tetrahydrofuran (THF). This material showed promise as a precursor for silicon nitride -silicon carbide-based ceramic materials. Due to the structure of the PVSZ polymer, the ability to stabilize (shelf-life) and dope with metals and metalloids has proven to be difficult. To overcome these problems, a second chlorosilane precursor, dichloromethylsilane, was introduced into the ammonolysis reaction. This polymer proved to be more stable (>3 months before cross-linking) and added a potential doping site on the backbone of the polymer while maintaining ceramic yields greater than 80%. The polymethylvinylsilazane (PMVSZ) polymer was characterized using attenuated total reflectance (ATR) spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, gel permeation chromatography (GPC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and elemental analysis. The results indicated that the ratio of chlorosilane precursors used plays an important role in the composition of crystallized ceramic material. P. Columbo-contributing editor Manuscript No. 30610.