In the research paper Synthesis of silver nanoparticles using microorganisms
by Z. SADOWSKI*, I. H. MALISZEWSKA,B. GROCHOWALSKA, I. POLOWCZYK, T. KOZ?LECKI is the results of testing the Zeta potential of silver nanoparticles vs pH of the solution.
The measurements show:
At pH of 2, Zeta potential is close to zero.
At pH of 4, Zeta potential is about 4 millivolts
At pH of 6, Zeta potential is about 23 millivolts
At pH of 8, Zeta potential is about 25 millivolts
Zeta potential is the electrostatic force keeping the uncapped/unstabilized silver particles from clumping together and falling out of solution. Greater Zeta potential equates to higher stability of the colloid.
