Fig. 1. Schematic of experimental setup

Fig. 2. Colloidal gold prepared for different laser irradiation durations

Fig. 3. UV-Vis absorption spectra of colloidal gold prepared for different laser irradiation durations

Fig. 4. TEM images and particle size distributions of gold nanoparticles prepared at different concentrations of solution. (a) 0.1 mmol·L-1; (b) 0.4 mmol·L-1; (c) 0.7 mmol·L-1; (d) 1.0 mmol·L-1

Fig. 5. (a) Particle size of gold nanoparticles and (b) UV-Vis absorption spectra of colloidal gold prepared in different concentrations of solution

Fig. 6. TEM images and particle size distributions of gold nanoparticles prepared at different laser pulse energies. (a) 93 μJ; (b) 163 μJ; (c) 235 μJ; (d) 320 μJ

Fig. 7. (a) Particle size of gold nanoparticles and (b) UV-Vis absorption spectra of colloidal gold prepared at different laser pulse energies

Fig. 8. TEM images and particle size distributions of gold nanoparticles prepared at different PVP amounts. (a) 0.2 mg; (b) 0.5 mg; (c) 1.0 mg

Fig. 9. (a) Particle size of gold nanoparticles and (b) UV-Vis absorption spectra of colloidal gold prepared at different PVP amounts

Fig. 10. SAED pattern of gold nanoparticle

Fig. 11. HRTEM image of gold nanocrystal (111) plane

Fig. 12. XRD pattern of gold nanocrystal