Small nanoparticles with size below 6 nm were obtained at pH~8 (NaOH), particles with size up to 50 nm and agglomerated form were received at pH~3 (HNO3). The concentration of silver precursor and reducing agent is omitted in this case.
The surface of the support was functionalized by (3-Aminopropyl)triethoxysilane and
(3-Mercaptopropyl)trimethoxysilane. Surface charge was related with protonation and deprotonation both entered and primary functional groups.
What effect may be responsible for this difference?
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