Nanocrystalline FeAs, CoAs and NiAs were prepared by keeping the mixture of
FeCl3, CoCl2 or NiCl2 with arsenic and KBH4 in ethylenediamine (en) at 100
degrees C for 4 h, respectively. X-Ray powder diffraction (XRD) patterns a
nd transmission electron microscope (TEM) images show that the products are
orthorhombic FeAs, CoAs and hexagonal NiAs, respectively, and all are well
crystalline in nanometers.