Figure 1: Structural design and characterizations of the disk TENG.

(a) Schematic illustrations and the photographs of the disk TENG. (b) The short-circuit current and (c) the open-circuit voltage of the as-fabricated disk TENG. (d) The short-circuit current and (e) the open-circuit voltage after applying a transformer with (blue dashed curve) and without (red solid curve) the cooling system.