Surface modification of aseptic carton package for energy harvesting devices

Triboelectric generators are electrostatic generators based on tribocharging (or contact electrification). Most of the triboelectric generators are constructed using expensive materials like gold thin films [1] and costly processes such as photolithography. In this work, we used aseptic carton packages in a low-cost scalable process to construct a triboelectric generator with efficiency comparable to recent devices reported in the literature. In fact, aseptic carton packages, mostly based on either Tetra Pak or SIG Combibloc systems, are composed from laminates of liquid packaging board, foil, and polyethylene and naturally present all parts required by a triboelectric system. As shown in the Scheme 1, the triboeletrization is enhanced by the surface modification of polyethylene, such as chemical, physical and electric processes. In the first moment, the polyethylene surface was oxidized and used as face of the tribogenerator while another polyethylene sheet was kept intact, obtaining potentials as high as 200 Volts. We were capable to store generated by our device in 4 capacitors of 2.2 μF during 3.5 minutes, reached 2.5 Volts. Moreover, the voltages obtained here are in the same order of magnitude of nanoengineered devices that were recently described in the literature [2] and we believe that using aseptic carton packages and another surface modification, could be a reliable way to construct energy harvesting and scavenging devices that may to collect energy through daily activities, like walking or driving, and use it for devices that require low power density.