Synthesis and Characterization of Au-Zn Nanoalloy by Laser Irradiation in Liquid Media

Abstract

Alloy nanoparticles due to their possibility of regulation, the region of absorption peak and consequently their optical and electrical properties, have a specific significance. In this research, nanosecond laser pulses of Nd:YAG laser with 532 nm wavelength that is close to absorption peak of gold and zinc nanoparticles, were used for synthesis of alloy. Atomic absorption spectrum UV-Visible, X-ray diffraction analysis and transmission electron microscopy images were utilized for characterization as well. For synthesis of Au-Zn alloy nanoparticles, zinc and gold nanoparticles were prepared separately by laser ablation method and then the mixture of their colloidal solutions with specified ratio was exposed to laser radiation. Thereby, gold and zinc nanoparticles were combined by absorbing of laser beam and gaining of required energy for melting, and Au-Zn alloy nanoparticles were formed. Wavelength of 532 nm is more effective in the formation of alloy than 1064 nm because of being close to wavelength of surface plasmon resonance of gold and zinc nanoparticles. Increase of concentration of gold nanoparticles compared to zinc nanoparticles in the mixed solution causes that gold nanoparticles absorb the most of the energy of laser and then larger gold particles are created, so alloy nanoparticles are not formed. The best time duration for irradiation and accomplishment of alloy formation is 30 min.

Tuning the Composition of Alloy Nanoparticles Through Laser Mixing: The Role of Surface Plasmon Resonance

“…Laser induced melting and mixing of metal nanoparticles in liquid media has demonstrated to be a good pathway for the formation of alloys 14 . In particular, the irradiation of gold with the Nd:YAG second harmonic has been used for the formation of Au-Ag alloys 15,16,17 , 18 ,Au-Zn 19 , Au-Cu 20 We also propose a physicochemical model, supported by theoretical temperature simulations, to explain the observed Au/Ni mixing behavior.…”

“…Laser-induced melting and mixing of metal nanoparticles in liquid media has been demonstrated to be a good pathway for the formation of alloys . In particular, the irradiation of gold with the Nd:YAG second harmonic has been used for the formation of Au–Ag alloys, − Au–Zn,Au–Cu, and Au–Fe . Here we use laser mixing of nickel and gold nanoparticle dispersions in liquid media, in order to obtain Au x Ni 1– x alloys with different compositions by varying the Au/Ni nanoparticle ratio in the starting mixtures.…”

Composition‐Controlled Laser‐Induced Alloying of Colloidal Au–Cu Hetero Nanoparticles

“…Due to the isochoric melting process, the composition of the individual particles does not change compared to the initial hetero nanoparticles. Thus, the composition (gold to copper ratio) of the laser-induced nanoalloys can be previously adjusted and controlled by wet chemical synthesis, which opens the door for controllable alloying processes of a variety of further metal systems such as Au-Ag, [21][22][23]25] Ag-Bi, [26] Au-Fe, [20] Au-Zn, [27] Fe-Pt, [28] and Ag-Pt, [29] whose alloy formation could already be observed by LAL and LFL methods. In principle, the implementation of this method is conceivable for all alloy-forming metal systems as long as they exhibit suitable absorption properties in the range of the laser wavelength.…”