Effect of Surfactant Concentration on the Size of One‐Pot Synthesized Si Nanoparticles

Abstract

The effect of surfactant concentration on the synthesis of Si nanoparticles (NPs) was studied. Hexyl Si NPs were synthesized using one‐pot synthetic methodology with different ratios of SiCl4:HexylSiCl3 (1:1, 1:2, 1:3, 1:6) to observe the effect of surfactant concentration on the size of Si NPs. In Fourier transform infrared spectroscopy analysis, the Si–H stretching band and the characteristic Si–O–Si bands decreased and eventually disappeared with increasing hexyltrichlorosilane concentration. This suggests that the level of oxidation decreased with excess amounts of hexyltrichlorosilane because the surface area of exposed Si NPs without hexyl capping groups was reduced. Results of transmission electron microscopy and particle size analysis showed that the average diameter of hexyl Si NPs increased slightly from low surfactant concentration (SiCl4:HexylSiCl3 = 1:1) to high concentration (1:6). This might be caused due to the relationship between the surfactant concentration effect and the core material part effect of hexyltrichlorosilane. Agglomerated Si NPs were observed and their luminescence bands were not shifted because the Si NPs were capped by alkyl groups to prevent aggregation.