Biosynthesis and characterization of Ti/Ni bimetallic nanoparticles

Small particles of Ti/Ni have been synthesized by a bioreduction method. The controlling parameter was the pH of the solution where they were grown in. HREM and high-angle annular dark field in the electron microscope have been used to characterize the morphology and structural properties of such small particles. Well controlled sizes in the range of 1-4 nanometers and with a structure based on an fcc-like geometry for the smallest clusters and with more complex arrays for larger clusters were obtained. In general it was demonstrated that the bimetal nanoparticles appear in a set of structures including the core-shell type, with Ni as the shell. (c) 2006 Elsevier B.V. All rights reserved.