A constant current triboelectric nanogenerator arising from electrostatic breakdown.

In situ conversion of mechanical energy into electricity is a feasible solution to satisfy the increasing power demand of the Internet of Things (IoTs). A triboelectric nanogenerator (TENG) is considered as a potential solution via building self-powered systems. Based on the triboelectrification effect and electrostatic induction, a conventional TENG with pulsed AC output characteristics always needs rectification and energy storage units to obtain a constant DC output to drive electronic devices. Here, we report a next-generation TENG, which realizes constant current (crest factor, ~1) output by coupling the triboelectrification effect and electrostatic breakdown. Meanwhile, a triboelectric charge density of 430 mC m is attained, which is much higher than that of a conventional TENG limited by electrostatic breakdown. The novel DC-TENG is demonstrated to power electronics directly. Our findings not only promote the miniaturization of self-powered systems used in IoTs but also provide a paradigm-shifting technique to harvest mechanical energy.