Citation: Ilie, C.-I.; Spoial ˘ a, A.; Motelica, L.; Marinescu, L.; Dolete, G.; Trus , c˘ a, D.-R.; Oprea, O.-C.; Ficai, D.; Ficai, A. Decoration of a Glass Surface with AgNPs Using Thio-Derivates for Environmental Applications. Coatings 2024, 14, 96. https://doi.org/10.3390/ coatings14010096 Academic Editor: Maria Jose Fabra Received: 7 December 2023 Revised: 3 January 2024 Accepted: 8 January 2024 Published: 11 January 2024 Copyright: © 2024 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/). coatings Article Decoration of a Glass Surface with AgNPs Using Thio-Derivates for Environmental Applications Cornelia-Ioana Ilie 1,2 , Angela Spoială 1,2 , Ludmila Motelica 1,2 , Liliana Marinescu 1,2 , Georgiana Dolete 1,2 , Doina-Roxana Trus , că 1,2 , Ovidiu-Cristian Oprea 3,4 , Denisa Ficai 4 and Anton Ficai 1,2,3, * 1 Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Chemical Engineering and Biotechnologies, National University of Science and Technology POLITEHNICA Bucharest, 060042 Bucharest, Romania 2 National Centre for Micro and Nanomaterials and National Centre for Food Safety, National University of Science and Technology POLITEHNICA Bucharest, 060042 Bucharest, Romania 3 Academy of Romanian Scientists, 050044 Bucharest, Romania 4 Department of Inorganic Chemistry, Physical Chemistry and Electrochemistry, Faculty of Chemical Engineering and Biotechnologies, National University of Science and Technology POLITEHNICA Bucharest, 060042 Bucharest, Romania * Correspondence: anton.ficai@upb.ro Abstract: The aim of this study is to decorate a glass surface with silver nanoparticles (AgNPs) and further prove its efficiency in the removal of some thio-derivatives—potential pollutants from water. Therefore, grafting the surface of glass-based platforms with AgNPs will strongly influence their interaction with other substances or molecules. The most commonly used molecules for glass- based platform functionalization/modification are organosilanes. In this case, the main interest is in thioalkyl organosilanes because, after silanization, the thio (-SH) functional groups that have a high affinity for AgNPs can intermediate their binding on the surface. By decorating the glass platforms with AgNPs, these surfaces become active for the adsorption of dyes from wastewater. Certainly, in this case, the dyes must bear -SH groups to ensure a high affinity for these surfaces. Therefore, the desired purpose of this study was to develop glass-based platforms decorated with AgNPs able to bind model molecules—dyes from aqueous media (dithizone—DIT and thioindigo—TIO), with these platforms being potentially used for environmental applications. Keywords: glass surface silanization; organosilanes; silver nanoparticles; dyes removal; pollution 1. Introduction The fabrication of solid glass-based surfaces with silver nanoparticle (AgNPs) assem- blies immobilized on their surfaces is currently of great importance because of the key role these substrates could play in developing various applications [1,2]. In this study, we have utilized the potential of glass-based platforms because they are economical, environ- mentally friendly, durable, reusable, and inert material, which has been demonstrated to be an excellent candidate in applications ranging from laboratory to industry [1,3]. The physicochemical properties of the obtained surfaces will depend on the size, shape, and surface features of the silver nanoparticles and the nature of the glass surfaces [4]. Normally, silver nanoparticles are attached to the glass surface/substrate through an intermediate layer of diverse molecules grafted on the surface. The grafting process is carried out with the help of the terminal functional groups due to their electrostatic or chemical interaction with the nanoparticles (NPs). The main characteristics of these surfaces/platforms are that they should be stable over time and their interaction with the NPs should be strong enough to ensure that the NPs continue to be attached to their surface during further functionalization [5,6]. The molecules commonly used for the functionalization of glass-based platforms are organosilanes, which are the most studied surface modifiers [7–9]. The affinity of the Coatings 2024, 14, 96. https://doi.org/10.3390/coatings14010096 https://www.mdpi.com/journal/coatings