METHOD FOR THE SIZE CONTROL OF AU NANOPARTICLE AGGREGATES BY ORGANIC SURFACTANTS

摘要

A method of adjusting size of gold nano-particle aggregate is provided to form a nano-particle with controlled particle size as desired by using constant amount of citrate as a reductant sufficient to obtain the desired particle size of nano-particle and adding organic adsorbent to the produced nano-particle to form the final aggregate. The method includes steps of (a) adding reductants with varied concentrations to a water solution of MAuX4 wherein M is H, K or Na and X is Cl or Br to form a colloidal solution containing Au nano-particles with varied average diameters; and (b) adding organic adsorbent to the colloidal solution to produce Au nano-particle coagulate by self-assembly of the Au nano-particles. The reductant is citrate or tartrate. The organic adsorbent is aromatic organic adsorbent having functional group selected from -CN, -SH, -NCS and -CNS.