Testing aluminium and polytetrafluoroethylene as triboelectric materials for acoustic triboelectric nanogenerators

Triboelectric Nanogenerator (TENG) is a green energy generating technology that can harvest energy from the surroundings such as ambient sound via contact-electrification and triboelectric effects. TENG works by exchanging electrons through different triboelectric materials to generate current flow. Polytetrafluoroethylene (PTFE) and Aluminium were selected to be the triboelectric materials of an Acoustic TENG due to their good flexibility, lightweight, low cost, recyclability and great affinities of the materials to a accept and donate electrons. A conventional speaker enclosed in an acrylic chamber was used to simulate the sinusoidal soundwave of the TAE. The TENG was tested with different sound frequencies to determine the optimum frequency for the electrical output of the system. The TENG can produce maximum and minimum open-circuit voltage of 2.36V and -2.76V at the sound frequency of 60Hz. At this frequency, the TENG can also generate 0.206 µW using 7 MΩ load resistance. The triboelectric pair of PTFE-Al generated significantly lower electrical output when compared to other PTFE-Al based TENG in scientific literature. The unexpected low output of this study’s TENG may occur due to poor contact and separation process between the active and the static layers of the TENG in this study. Further improvements need to be made to the design of the TENG to ensure proper separation of the triboelectric layers during the energy conversion process.