Patent ID: 7718710
Filing Date: 2010-05-18
Classification: B01J,B22F,B82Y

Abstract:
1. A method for making a stabilized concentrated metal colloid, comprising: (i) mixing together a solvent, a plurality of metal atoms, and a plurality of organic agent molecules, each organic agent molecule comprising at least one functional group capable of forming an anion having an electron for donation to and bonding with a metal atom; (ii) reacting the metal atoms with the organic agent molecules to form a mixture comprising a plurality of complexed metal atoms in which anions provided by the organic agent molecules are complexed with the metal ions; (iii) reducing the complexed metal atoms in the mixture using a reducing agent to form a plurality of nanoparticles, the reducing agent releasing acidic protons during reduction of the metal ions; and (iv) adding an amount of a weak base to the mixture in order to raise the pH to at least about 4.5 and counteract acidification resulting from the reduction of the metal atoms, thereby improving the stability of the nanoparticles in the mixture,