The synthesis process can be broken down into the following steps:
Dissolution: Gold (III) chloride (HAuCl4) is dissolved in water. Heating: The solution is heated to boiling. Reduction: Sodium citrate is added to the boiling solution, reducing gold ions (Au3+) to gold atoms (Au0). Nucleation: Gold atoms nucleate to form nanoparticles. Growth and Stabilization: Citrate ions stabilize the growing nanoparticles, preventing aggregation.
