Publications by authors named "Gregory R Schwenk"

When a few drops of acid (hydrochloric, acrylic, propionic, acetic, or formic) are added to a colloid comprised of 1D lepidocrocite titanate nanofilaments (1DLs)-2 × 2 TiO octahedra in cross-section-a hydrogel forms, in many cases, within seconds. The 1DL synthesis process requires the reaction between titanium diboride with tetramethylammonium (TMA), hydroxide. Using quantitative nuclear magnetic resonance (qNMR), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC), the mass percent of TMA after synthesis is determined to be ≈ 13.

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Truly one-dimensional titanium oxide nanofilaments with a lepidocrocite structure (1DLs) were explored in the adsorption and photocatalytic degradation of aqueous malachite green (MG), a toxic polluting dye. Decolorization is monitored by ultraviolet-visible spectroscopy, and mineralization is confirmed by total organic carbon analysis. The 1DL/MG flocs are characterized by scanning electron microscopy and X-ray diffraction.

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Herein, the self-assembly of one-dimensional titanium oxide lepidocrocite nanofilaments in 10 different water miscible organic solvents was investigated. The nanofilament snippets, with minimal cross sections of ∼5 × 7 Å and lengths around 30 nm, begin as an aqueous colloidal suspension. Upon addition, and brief mixing, of the colloidal suspension into a given solvent, a multitude of morphologies─seemingly based on the hydrophilicity and polarity of the solvent─emerge.

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Since the onset of the SARS-CoV-2 pandemic, the world has witnessed over 617 million confirmed cases and more than 6.54 million confirmed deaths, but the actual totals are likely much higher. The virus has mutated at a significantly faster rate than initially projected, and positive cases continue to surge with the emergence of ever more transmissible variants.

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Black phosphorus (BP) has been gathering great attention for its electronic and optoelectronic applications due to its high electron mobility and high I current switching ratio. The limitations of this material include its low synthetic yield and high cost. One alternative to BP is another type of phosphorus allotrope, red phosphorus (RP), which is much more affordable and easier to process.

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