Effect of Sodium Hydroxide on the Particle Diameter of Copper Nanoparticles Synthesized by Liquid Phase Method Using Sodium Borohydride

The effect of NaOH on the synthesis of Cu nanoparticles was evaluated. For synthesis, the reducing agent used was NaBH4, the polymer protective agent was PVP, and the source of copper was Cu(OH)2. The highest generation of hydrogen as a reaction by-product occurred after 59 min of reaction when NaOH was added; this was an increase from 43 min for the case where NaOH was not added. The proportion of the volume of Cu nanoparticles 20 nm or more in diameter to the total volume changed from 0.7% to 73.9%.