“…The explosion in academic and industrial interest in these materials over the past decade arises from the remarkable variations in their electrical, optical, magnetic, and catalytic properties. Different methods have been used to synthesize metallic nanoparticles [ 4 , 5 , 6 ]. The most important are (i) chemical reduction, which involves the reduction of metal salts in solution or suspension by reducing agents; (ii) thermal decomposition by heating volatile metal compounds in an organic medium or gas phase, causing their degradation with the release of metals or their oxides in the dispersed phase; (iii) chemical vapor deposition in which the vaporized precursors are adsorbed onto a substance held at an elevated temperature; (iv) ultrasonic and microwave irradiations in which the direct interaction between microwaves and materials and this fact enables a uniform and fast heating of a sample; and (v) electrochemistry methods in which the particle size can be controlled by varying the electrical density, temperature, solvent polarity, and the distance between the electrodes.…”