Natural sepiolite modified PVDF electrospun films for mechanically robust and high-performance triboelectric nanogenerators

In this work, natural sepiolite and polyvinylidene fluoride (PVDF) electrospun composite films with improved mechanical strength were prepared successfully, in which the natural sepiolite not only decreased fiber slippage, but also promoted the polar 8-phase formation to reduce surface potential. It was found that the 25 wt% natural sepiolite modified PVDF film (PVDF-25) achieved a 3.2-fold enhancement in tensile strength. The surface potential decreased to -1.439 V in the 15 wt% natural sepiolite modified PVDF film (PVDF-15). Furthermore, through utilizing this mechanically robust film as triboelectric material, the triboelectric nanogenerator (TENG) held superior output performances, including the open-circuit voltage of 740 V, short-circuit current density of 60 mA/m2, maximum power density of 94.08 W/m2 and the long-term stability over 1000 cycles. This work may provide new insights in developing mechanically and electrically robust triboelectric materials by combining natural clay materials.