Porous TENG mounted on the insoles. (a) Diagram of the synthesis process. (b) The process of generating electricity from a single cavity. (c) SEM magnified view of the inner surface, with exposed CNTs labeled. (d) Photograph of an as-prepared round PNC (5 cm in diameter and 0.5 cm thick). The SEM inset shows the surface morphology. (e) Cycled ISC
and corresponding status of a foot under repeated normal walking. Reproduced with permission from [159
]. Copyright Wiley-VCH, 2016.