Figure 3

XRD of ‘standard’ porous silicon manifesting presence of the crystalline silicon phase. Estimated nanocrystal size from the Scherrer equation is 4 nm. Inset shows a photograph of final colloidal solution - stable ‘standard’ porous silicon nanoparticles in methanol. Sample is filtered by the 1-μm syringe filter and shows strong orange photoluminescence under illumination by 325-nm line of the HeCd laser.