The Effect of Applied Electric Field on Hydrogen Incorporation During the Formation of Au Nanoparticles Fabricated by Laser Ablation

Abstract

In the present study, gold nanoparticles (NPs) were fabricated by pulsed laser ablation (PLA) method in distilled water environment  under different external electric field strengths. The effect of the electric field on the characteristics of produced NPs was traced  through X-ray diffraction (XRD), Fourier transforms infrared (FT-IR) and transmission electron microscopy (TEM). Optical properties  were studied by UV-visible spectroscopy. The XRD results showed an orthorhombic lattice, alongside the typical cubic structure of Au, which was  attributed to the hydrogen incorporation in the crystalline structure of Au nanoparticles. The interaction between hydrogen and gold did  not vary linearly with the increased of applied electric field. At an electric field of 20 V/cm, this interaction was almost negligible. Furthermore, the peak observed at around 2000 cm−1 in the FT-IR spectrum provided additional evidence for possible Au-H interactions.  Based on the TEM images, some non-spherical shapes such as nanorods were successfully synthesized under higher electric field  strengths. Moreover, the interaction between hydrogen and gold likely induced a slight blue shift in the UV-Vis spectrum. The formation  of Au hydride makes our sample a promising candidate for use as anoptical hydrogen sensor; however, further research is needed.