Preparation and Characterization of Au Quantum Dots Using Laser in Benzene and Study of the Pulse Energy effect on Quantum Size

Abstract

Here, findings from a study on pulsed laser ablating of noble Au targets submerged in benzene solvent and a study on the effect of pulse energy on quantum size are presented. Three samples of gold quantum dots (AuQDs) are synthesized at pulse fluence of 4, 8, and 12 J/cm2, which is referred to as F1, F2, and F3, respectively. The prepared AuQDs were characterized by UV-Vis, HR-TEM, XRD, XPS, EDX, FTIR, Raman spectroscopy and Photoluminescence measurement. AuQDs that were synthesized have monocrystalline and cubic (FCC) structure, according to XRD patterns. It was found that the direct optical energy gap of AuQDs is enhanced to 2.6 eV. The emission peak of AuQDs photoluminescence emission spectra is at roughly 481, 445, and 437 nm, for F1, F2, F3 samples, respectively. The quantum size was reduced to 2 nm for sample F3. This strategy has the ability to prepare pure AuQDs in one step, with promising biosensor and bioimaging applications.