Improved adhesion of Ag NPs to the polyethylene terephthalate surface via atmospheric plasma treatment and surface functionalization

•A two-step process has been developed to enhance the adhesion of immobilized Ag NPs to the PET surface.•The method is simple, easy to use and low-cost for mass production.•The increased density of active sites (OH, CHO and COOH) at the PET surface, after plasma treatment, permits increased reaction with 3-aminopropyltriethoxysilane (APTES).•The presence of APTES with high surface density permits NH2-Ag complex formation, increasing the adhesion of the Ag NPs.