Magnetic field-assisted solvothermal assembly of one-dimensional nanostructures of Ni-Co alloy nanoparticles

One-dimensional (1D) chainlike Ni0.33Co0.67 alloy nanostructures and wirelike Ni0.67Co0.33 alloy nanostructures were solvothermally prepared at 180 degrees C under an external magnetic field. The morphologies and structures of these samples were characterized by powder X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HRTEM). Magnetic measurement results reveal that both of these two nanostructures possess higher saturation magnetization M-s, remnant magnetization M-r, coercivity H-c and reduced magnetization M-r/M-s, compared with those of randomly distributed alloy particles prepared in the absence of an external magnetic field. A possible growth mechanism was proposed to account for the microscopic assembly behaviors induced by the applied magnetic field. Crown Copyright (C) 2009 Published by Elsevier B.V. All rights reserved.