Growth of spindle-shaped gold nanoparticles in cetyltrimethylammonium bromide solutions

Spindle-shaped gold nanoparticles were successfully prepared in high yield by a simple wet chemical approach using L-ascorbic acid (AA) as reductant in the presence of cetyltrimethylammonium bromide (CTAB) at room temperature. Transmission electron microscopy, ultraviolet-visible absorption spectroscopy and X-ray diffraction have been used to characterise the obtained products. It is found that the spindle-shaped architecture of gold nanoparticles is drastically influenced by the mass ratio of CTAB/AA, CTAB/HAuCl₄, HAuCl₄/AA and the concentration of CTAB, AA, HAuCl₄. It is revealed that CTAB might play an adsorbent role.