A novel polyol method to synthesize colloidal silver nanoparticles by ultrasonic irradiation

A polyol synthesis of silver nanoparticles in the presence of ultrasonic irradiation was compared with other configurations (at ambient temperature, 120 degrees C, and 120 degrees C with injected solutions) in the absence of ultrasonic irradiation in order to obtain systematic results for morphology and size distribution. For applying ultrasonic irradiation, rather fine and uniform spherical silver particles (21 +/- 3.7 nm) were obtained in a simple (at ambient temperature without mechanical stirring) and fast (within 4 min, 3.61 x 10(-3) mol min(-1)) manner than other cases (at ambient temperature (for 8 h, 0.03 x 10(-3) mol min(-1)): 86 +/- 16.8 nm, 120 degrees C (for 12 min, 1.16 x 10(-3) mol min(-1)): 64 +/- 14.9 nm, and 120 degrees C with injected solutions (during 12 min): 35 +/- 6.8 nm; all other cases contained anisotropic shaped particles). Even though the temperature of polyol reaction reached only at 80 degrees C (<120 degrees C) in the presence of ultrasonic irradiation, a uniform mixing (i.e. enhanced collision between silver particle and surrounding components) by ultrasonic irradiation might induce a better formation kinetics and morphological uniformity. (C) 2011 Elsevier B.V. All rights reserved.