The data in this work provides the effect of aging temperature on manganese oxide allotropes prepared by hydrothermal method in the presence of boron dopant. The synthesized samples were labeled as B/MnO -100, B/MnO -150, and B/MnO -180 corresponding to the hydrothermal temperature at 100, 150, and 180 °C, respectively. X-ray diffraction (XRD) and inductively coupled plasma mass spectrometry (ICP-MS) methods were conducted to clarify the crystalline structure, as well as the amount of potassium, manganese, and boron elements in the three synthesized samples.
View Article and Find Full Text PDFIn this study, we demonstrate three-dimensional (3D) hollow nanosphere electrocatalysts for CO conversion into formate with excellent H-Cell performance and industrially-relevant current density in a 25 cm membrane electrode assembly electrolyzer device. Varying calcination temperature maximized formate production via optimizing the crystallinity and particle size of the constituent SnO nanoparticles. The best performing SnO nanosphere catalysts contained ~ 7.
View Article and Find Full Text PDFA-site and B-site substitutions are effective methods towards improving well-studied oxygen carrier materials that are vital for emerging gasification technologies. Such materials include SrFeO , which greatly benefits from the inclusion of calcium and/or cobalt, and Sr Ca Fe Co O has been regarded as the best-performing composition. In this study, systems with higher calcium and lower cobalt contents are investigated with a view to lessening the societal and economic burdens of these dual-doped carriers.
View Article and Find Full Text PDFThe splitting of water into molecular hydrogen and oxygen with the use of renewable solar energy is considered one of the most promising routes to yield sustainable fuel. Herein, we report the H evolution performance of gallium doped TiO photocatalysts with varying degrees of Ga dopant. The gallium(iii) ions induced significant changes in the structural, textural and electronic properties of TiO nanoparticles, resulting in remarkably enhanced photocatalytic activity and good stability for H production.
View Article and Find Full Text PDFAmbient pressure in situ synchrotron-based spectroscopic techniques have been correlated to illuminate atomic-level details of bond breaking and formation during the hydrolysis of a chemical warfare nerve agent simulant over a polyoxometalate catalyst. Specifically, a Cs[NbO] polyoxoniobate catalyst has been shown to react readily with dimethyl methylphosphonate (DMMP). The atomic-level transformations of all reactant moieties, the [NbO] polyanion, its Cs counterions, and the DMMP substrate, were tracked under ambient conditions by a combination of X-ray absorption fine structure spectroscopy, Raman spectroscopy, and X-ray diffraction.
View Article and Find Full Text PDFThree-dimensional (3D) monodispersed sea urchin-like Ru-doped rutile TiO2 hierarchical architectures composed of radially aligned, densely-packed TiO2 nanorods have been successfully synthesized via an acid-hydrothermal method at low temperature without the assistance of any structure-directing agent and post annealing treatment. The addition of a minuscule concentration of ruthenium dopants remarkably catalyzes the formation of the 3D urchin structure and drives the enhanced photocatalytic H2 production under visible light irradiation, not possible on undoped and bulk rutile TiO2. Increasing ruthenium doping dosage not only increases the surface area up to 166 m(2) g(-1) but also induces enhanced photoresponse in the regime of visible and near infrared light.
View Article and Find Full Text PDFNi-CeO2 is a highly efficient, stable and non-expensive catalyst for methane dry reforming at relative low temperatures (700 K). The active phase of the catalyst consists of small nanoparticles of nickel dispersed on partially reduced ceria. Experiments of ambient pressure XPS indicate that methane dissociates on Ni/CeO2 at temperatures as low as 300 K, generating CHx and COx species on the surface of the catalyst.
View Article and Find Full Text PDFNanocomposite materials containing graphene oxide have attracted tremendous interest as catalysts and adsorbents for water purification. In this study, mesoporous titanosilicate/reduced graphene oxide composite materials with different Ti contents were employed as adsorbents for removing bisphenol A (BPA) from water systems. The adsorptive interaction between BPA and adsorption sites on the composite materials was investigated by Fourier transform infrared (FT-IR) and Raman spectroscopy.
View Article and Find Full Text PDFReduced graphene oxide-TiO(2) hybrids were successfully prepared by the hydrothermal approach using triethanolamine and acetylacetone as the chelating agents. Without any additive, large aggregated TiO(2) clusters were randomly distributed dominantly at the edge and less on the basil plane of coagulated reduced graphene oxide (RGO) layers. The presence of chelating ligands remarkably facilitated the selective growth and regular spread of TiO(2) nanocrystals onto individually exfoliated RGO sheet.
View Article and Find Full Text PDFThe ultra-low density graphene xerogel was prepared through the chemical reduction of graphene oxide suspension using a hypophosphorous acid-iodine mixture. The chemically converted graphene xerogel (CCGX) exhibited superior electrical conductivity (up to 500 S m(-1)) and high C/O atomic ratio (14.7), which were the highest values reported for the graphene-based xerogel.
View Article and Find Full Text PDFNovel hierarchical rose bridal bouquet- and humming-top-like nanostructured TiO(2) were successfully prepared by the simple process with the hydrothermal temperature as the morphology-controlling factor. The gradual transformation from layered titanate to brookite phase was well consistent with the formation mechanism of the hierarchical morphologies. The three-dimensional flower bouquets built from the bunches of roses with surrounding fern fronds displayed the best adsorptivity and completely degraded methylene blue within 60 min under UV irradiation, whereas the humming-top geometry composed of anisotropically elongated spindle-like crystallites was detrimental to the dye photodegradation.
View Article and Find Full Text PDFChemically converted graphene that was reduced with phenylhydrazine was highly dispersed in organic solvents, and its "paper" prepared by filtration of the reduced graphene possessed an electrical conductivity value as high as 20,950 S m(-1).
View Article and Find Full Text PDFThe adsorptive removal of benzene from cerium- and lanthanum-doped mesoporous TiO2 adsorbents was performed in a continuous-flow, fixed-bed reactor. The influences of lanthanide content and adsorption temperature were investigated. The adsorption efficiency of benzene was remarkably promoted in the presence of lanthanide.
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