GROWTH OF NANOMETRIC GOLD PARTICLES IN SOLUTION-PHASE

The time evolution of colloidal gold particles in the nanometric regim e has been investigated by employing electron microscopy and electroni c absorption spectroscopy. The particle size distributions are essenti ally Gaussian and show the same time dependence for both the mean and the standard deviation, enabling us to obtain a time-independent unive rsal curve for the particle size. Temperature dependent studies show t he growth to be an activated process with a barrier of about 18 kJ mol (-1). We present a phenomenological equation for the evolution of part icle size and suggest that the growth process is stochastic.