Stabilization of Au nanoparticles prepared by laser ablation in chloroform with free-base porphyrin molecules
Abstract
Laser ablation (LA) of a Au foil immersed in chloroform and/or in diluted 5,10,15,20-tetrakis-4-pyridylporphine (TPyP) chloroform solutions was carried out using 1064 nm nanosecond laser pulses. The products were characterized by UV-visible-NIR optical extinction and IR absorption measurements, Raman spectroscopy and transmission electron microscopy (TEM).
Our results show that with highly focused laser beam chloroform underwent photochemical reactions and no nanoparticles with observable surface plasmon extinction (SPE) band were formed whereas at particular focusing conditions Au nanoparticles with the SPE band typical for Au organosols were created. When a small amount of TPyP was present in the course of LA both the efficiency of Au nanoparticles formation and the stability of the resulting organosols were improved.