The photothermal effect of gold nanoparticles prepared by electrochemical method at different voltages

Abstract

This paper was performed to evaluate the photothermal effect of pure gold nanoparticles (AuNPs) prepared by electrochemical method at different voltages, under laser irradiation in the safe wavelength range. The formation, morphological, and structural properties of AuNPs were analyzed by UV-vis absorption spectroscopy, transmission electron microscopy (TEM), and X-ray diffraction (XRD). The stability and dispersion of AuNPs were investigated by dynamic light scattering (DLS) and Zeta potential measurements. The photothermal effect was evaluated by the temperature change of the sample under the green laser irradiated at a wavelength of 532 nm. The results showed the formation of the AuNPs has a spherical shape and high purity; the particle size distribution is in the range of 10 - 40 nm depending on the synthesis voltage, and the absorption peak is in the range of 530 to 556 nm. The temperature of the AuNPs solution increased by 1.3 to 6 oC, compared to that of bi-distilled water under the same conditions of laser irradiation. This paper shows the photothermal effect of AuNPs prepared by the electrochemical method at different voltages, it changed markedly when irradiated with a green laser in the safe wavelength range.