Structural and Electronic Properties of Pulsed Laser Deposited Ru Nanocrystals on SiO ₂

Metallic nanoparticles are a powerful and versatile tool for various applications: catalysis and electrochemistry, chemical sensing, nonvolatile information storage, and plasmonics. Nanoparticles made of ruthenium (Ru) are particularly promising due to enhanced catalytic activity, high structural, and chemical stability. However, existing methods for Ru nanoparticle synthesis are not always favorable for applications, with major issues being proneness to aggregation at high temperature operation or functionality and performance degradation due to amorphous structure. In this work, a method to synthesize Ru nanocrystals on the SiO 2 surface using a pulsed laser deposition technique at 600 °C is presented. This study thoroughly characterizes the morphological, structural, and electronic properties of the nanocrystal arrays and shows that their size can be tuned with the number of laser pulses during the growth up to the limit of percolation threshold. The formation of Ru nanocrystals is favored by the emergence of interface dipole between Ru and SiO 2 during deposition. The high growth temperature ensures improved heating stability of the Ru nanocrystals, which can be implemented in various appropriate applications.