A series of Fe-P-B ultrafine amorphous alloy particles were synthesized by chemical reduction method to study the influence of iron precursors such as FeCl2 center dot 4H(2)O, FeCl3 center dot 6H(2)O, and Fe(OAc)(2) and reaction medium (H2O, 50% ethanolic solution, and 50% isopropyl alcoholic solution). The physicochemical properties of the as-synthesized materials were characterized by X-ray diffraction, inductively coupled plasma-atomic emission spectroscopy, N-2 sorption, transmission electron microscopy, X-ray photoelectron spectroscopy, and electron diffraction. The existence of amorphous nature of Fe-P-B materials was found to be retained even when the temperature was up to 300 degrees C. Use of different iron precursors and solvents in the preparation significantly influenced the structure, morphology, and composition of Fe-P-B nanoalloys. Dehydrogenation of ethanol has been carried out in order to evaluate the catalytic properties of the Fe-P-B nanoalloys and the results have been related to the surface properties of Fe-P-B nanoalloys. Fe-P-B prepared with FeCl2 in 50% ethanolic solution, showed the highest activity among all the Fe-P-B catalysts. (C) 2008 Elsevier B.V. All rights reserved.