We herein report our investigation into the effect of plasma-induced surface modification of a polyethylene terephthalate (PET) surface on the output performance of a triboelectric generator (TEG). The PET surface was subjected to plasma treatment using a CF4/CH4/Ar gas mixture (25-75% CF4) to increase the surface roughness and triboelectric charge density. Plasma diagnostics were then performed using optical emission spectroscopy and a double Langmuir probe, while analysis of the surface roughness and surface characteristics was performed using atomic force microscopy and X-ray photoelectron spectroscopy, respectively. Following.plasma treatment, we prepared a triboelectric energy harvester device, and demonstrated an outstanding improvement in TEG short-circuit current measurements. (C) 2017 Elsevier B.V. All rights reserved.