Textile-based triboelectric nanogenerator with alternating positive and negative freestanding grating structure

This paper reports a novel design of textile-based triboelectric nanogenerator (TENG) with alternate grated strips of positive and negative triboelectric material operating in freestanding triboelectric-layer mode, defined as a pnG-TENG. Whereas most grating-structured TENGs operating in a freestanding triboelectric-layer mode comprise gratings of one type of triboelectric material separated by air gaps, this design presents a replacement of the air gaps by another triboelectric material with the opposite polarity to the existing triboelectric material. This is predicted to increase performance by increasing the contact area of the generator. The pnG-TENG with 10 gratings of nylon fabric and PVC heat transfer vinyl delivers an RMS open-circuit voltage of 136 V, an RMS short-circuit current of 2.68 μA and a maximum RMS power of 125 μW at a load resistance of 50 MΩ, a mechanical oscillation of 2 Hz and a contact force of 5 N. This corresponds to a maximum RMS power density of 38.8 mW/m2, which is 1.94 and 6.43 times greater than the power generated by the TENG with a single triboelectric material and the TENG with no gratings, respectively.