A series of ultafine Ni−P, Ni−B, and Ni−P−B amorphous alloy catalysts with various atomic ratios were prepared by a chemical reduction method. The catalysts were characterized with respect to elemental analysis, nitrogen sorption, XRD, TEM, XPS, and hydrogenation activity. Conventional Raney nickel was included for comparison. The Ni/P/B molar ratio in the starting material significantly affected the concentration of boron and phosphorus bonded to the nickel metal, subsequently affecting the surface area, the amorphous structure, and the hydrogenation activity and selectivity of the catalyst. The different electron transfer between nickel metal and the metalloid elements in Ni−P and Ni−B powders (phosphorus draws electrons and boron donates electrons) results in the extremely different hydrogenation activity of furfural (specific activity per surface area: Ni85.0P15.0 ≫ Ni71.4B28.9). By regulating a suitable P/B ratio, the ultrafine Ni−P−B catalyst dramatically revealed a markedly higher hydrogenation activity of furfural than Ni−P and Ni−B. The specific activities per surface area of the catalyst are in the order Ni74.5P12.1B13.4 > Ni72.5P2.0B25.5 > Ni85.0P15.0 ≫ Ni71.4B28.9 > Raney nickel. The phosphorus is an active component to improve the selectivity of furfuryl alcohol. The hydrogenation of furfural is catalyzed actively by the Ni−P x −B y catalysts, following the first order with respect to the concentration of furfural. The nature of the ultrafine amorphous structure and the P/B ratio are the keys to manipulate the catalytic properties of Ni−P x −B y amorphous alloy catalysts.

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The ultra®ne Ni±B and Ni±P amorphous alloy catalysts were prepared by the chemical reduction method. The catalysts were characterized with respect to ICP-AES, XRD, nitrogen sorption, DSC, SEM, TEM and XPS. Nitrobenzene hydrogenation was used to compare their hydrogenation abilities. The different metalloids of boron and phosphorus bound to the nickel metal for the Ni±B and Ni±P catalysts result in the distinct different surface area, amorphous structure and hydrogenation activity of the catalysts. Ni±B had a larger surface area than Ni±P. The speci®c activity per surface area of Ni±P was greater than that of Ni±B. The different activities between the Ni±P and Ni±B can be attributed to the difference of the electron density on the nickel metal; boron donates electrons to the nickel metal and phosphorus accepts electrons from the nickel metal. The catalysts were easier to oxidize when they were exposed to air. This would result in the lower activity. However, the activity could be recovered in the reaction process due to the presence of hydrogen in the reaction system.

Fe-B amorphous nanoalloy materials have been synthesized by chemical reduction method using various iron precursors and preparation mediums. The samples have been characterized by X-ray diffraction, inductively coupled plasma atomic emission spectroscopy, N 2 sorption, transmission electron microscopy, X-ray photoelectron spectroscopy, differential scanning calorimetry, and electron diffraction. A series of studies have been performed to elucidate the influences of preparation parameters on the properties of Fe-B nanoalloys. The characterization results indicated that the amorphous nature of Fe-B materials remained up to 400 °C and the presence of boron retarded the crystallization of Fe sample. The iron precursor and preparation medium play a critical role in determining the structure, morphology, and composition of Fe-B nanoalloys. The iron precursors have a significant influence on the oxidation states of iron and boron species in Fe-B nanoalloys. The catalytic activities of Fe-B nanoalloys have been investigated by subjecting them for dehydrogenation of ethanol as a probe reaction. The results indicated that Fe 72.8 B 27.2 , prepared using FeCl 3 in aqueous medium, showed high activity for dehydrogenation of ethanol owing to its high surface area and turnover frequency.

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