The evolution of sphere- and rod-shaped superparamagnetic Ni-Pd and Ni-Pt nanoparticles by wet chemical methods is reported. It has been shown that increased CTAB (cetyltrimethyl ammonium bromide) concentration at room temperature promotes the formation of a higher proportion of rod-shaped nanomagnets over spherical particles. Temperature-dependent magnetic properties, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and electron dispersive X-ray (EDX) studies reveal the superparamagnetic behavior, size distribution, and percentage composition of the alloyed structures. (C) 2003 Elsevier Inc. All rights reserved.