Physical and Chemical Surface Modification of Recycled Polystyrene Films for Improved Triboelectric Properties

Polystyrene (PS) is a very common material in packaging. In this study, it is recycled by turning it into energy harvesting devices: triboelectric generators. Herein, heat-pressed films of recycled PS are formed and their surfaces are modified physically and chemically. The triboelectric properties of the films are determined using a dynamic testing machine, and the performance of the triboelectric generators is evaluated with a high-speed contact–separation system. The developed charge density of the triboelectric generator increases two orders of magnitude—from 0.03 to 1.52 nC cm⁻²—by combining these surface modification methods. Such high values of charge density enable the production of single material triboelectric generators.