Ultrastrong-polar polyacrylonitrile organic-inorganic architected nanogenerators with synergistic triboelectric behavior for efficient biomechanical energy harvesting and self-powered sensing

Accompanying the boom in smart wearable electronics, triboelectric nanogenerators (TENGs) as burgeoning mechanical-to-electrical harvesters have drawn expanding interest. In this study, a kind of novel flexible, high-output TENGs with PAN/FCNT as tribopositive layer and PVDF/PDMS/TiO2 as tribonegative layer have been designed and developed. For a synergistic effect, PAN and PVDF possessing strongly polar -CN and -F groups are handpicked as dielectric hosts to ensure maximum charge induction and triboelectrification. Highly conductive FCNT is introduced into the insulated PAN tribopositive layer, serving as the charge transport path to reduce surface charge loss. Additional PDMS is beneficial to strengthen the triboelectronegativity of PVDF tribonegative layer, and engaged as the charge trapping sites to diminish electro-discharge in air. TiO2 is employed as filler to build an inorganic-organic (TiO2-PVDF/PDMS) composite dielectric layer because of its triple functions of potent electron capture, high dielectric constant, and promoting the formation of electroactive β-phase PVDF. Meanwhile, the hydrogen bonds between PVDF, TiO2 with semi-crosslinked PDMS can stabilize interface and enhance friction output. Consequently, the assembled TENGs exhibit an ultra-high peak-to-peak voltage of 2088 V and a maximum output power of 7.2 W/m2, which shows promising applications in energy supplying and self-powered sensing fields.