Citation: De Muijlder, T.; Voué, M.; Leclère, P. Laser Ablation Synthesis of Silver Nanoparticles for Polymer Nanocomposites. Energies 2023, 16, 4625. https://doi.org/10.3390/ en16124625 Academic Editor: Antonino S. Aricò Received: 13 April 2023 Revised: 31 May 2023 Accepted: 8 June 2023 Published: 10 June 2023 Copyright: © 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). energies Article Laser Ablation Synthesis of Silver Nanoparticles for Polymer Nanocomposites Thomas De Muijlder 1 , Michel Voué 2 and Philippe Leclère 1, * 1 Laboratory for Physics of Nanomaterials and Energy (LPNE), Research Institute for Materials Science and Engineering, University of Mons (UMONS), 20 Place du Parc, B-7000 Mons, Belgium 2 Physics of Materials and Optics Unit (LPMO), Research Institute for Materials Science and Engineering, University of Mons (UMONS), 20 Place du Parc, B-7000 Mons, Belgium; michel.voue@umons.ac.be * Correspondence: philippe.leclere@umons.ac.be; Tel.: +32-65-373868 Abstract: Silver nanoparticles were synthesized via laser ablation in two different organic solvents (tetrahydrofuran and toluene). The influence of solvent choice on the production and behavior of silver nanoparticles dispersed in a polystyrene matrix was investigated. UV–Vis spectroscopy, ellipsometry and scanning probe microscopy techniques were used for characterization. The silver nanoparticles’ optical properties were modified by the existence of a core-shell structure appearing in toluene-ablated particles. For both solvents and, in particular, for the toluene case, the particles showed good dispersion in the matrix. Additionally, the interphase behavior of the doped polymer films was influenced by the synthesis process, affecting the mechanical and optical (dielectric) properties. The observed results for the nanocomposite are attributed to the formation of a core- shell structure around the particles directly due to the ablation in organic solvents. These findings contribute to the understanding of silver/polystyrene nanocomposites and offer opportunities for developing tailored functional materials by using laser ablation in liquids. Keywords: interphase; scanning probe microscopy; plasmonic nanocomposites; nanodielectrics; silver nanoparticles; polystyrene 1. Introduction During the last decades, polymer nanocomposites took a growing share of interest in the area of material sciences [1–4]. It is a field of nanotechnology dedicated to the study of a class of materials made of a nanofiller dispersed in a polymer matrix. The incorporation of nanofillers, such as nanoparticles, nanotubes, or nanosheets, into polymers offers unique op- portunities to tailor the properties of the resulting composite materials. Polymer nanocom- posites find applications in various industrial and environmental applications [5]. They hold great potential for lightweight structural components, high-performance coatings, flexible electronics, energy storage devices, and drug delivery systems, among others [6]. In particular, studies on nanodielectrics have revealed unusual electrical properties that are not simply a weighted mean of the component properties. These changes have been observed in numerous nanocomposite properties, including electrical susceptibility and complex dielectric permittivity. For instance Yang et al. [7] show significant enhancement of the dielectric constant of polystyrene/BaTiO 3 . The measured changes have significant implications for the applications of high-performance nanodielectrics in energy-storage devices [8]. Overall, the changes observed in several nanocomposite properties show great promise for the development of new and improved materials in a variety of fields. It has also been shown that the performance of polymer nanocomposite materials is strongly influenced by the presence of an interphase region at the interface between the filler and the matrix [9]. Because of the use of a nano-filler with a high surface-to-volume ratio, the interface effect plays a main contribution in the overall material properties. Energies 2023, 16, 4625. https://doi.org/10.3390/en16124625 https://www.mdpi.com/journal/energies