Microwave synthesis of gold nanoparticles: Effect of applied microwave power and solution pH

We describe formation kinetics of gold nanoparticles (AuNPs) in microwave synthesis. Using high microwave power to increase the temperature ramping rate (R-r) homogeneous nucleation is facilitated and the size of the resultant nanoparticles is reduced while the uniformity is much improved. Adjusting solution pH to higher than 6.2 could also have a positive effect on the quality of the nanosol. We therefore demonstrate that by adjusting these reaction parameters in microwave synthesis, we successfully produced uniform colloidal AuNPs with diameter of 12.04 +/- 1.35 nm in a few minutes. (C) 2011 Elsevier B.V. All rights reserved.