Inspired by treefrog's toe pads that show superior frictional properties, herein, an industrially compatible approach is reported to make an efficient dielectric tribosurface design using customizable nonclosepacked microbead arrays, mimicking the friction pads of treefrogs, in order to significantly enhance electrification performance and reliability of triboelectric nanogenerator (TENG). The approach involves using an engineering polymer to prepare a highly ordered large-area concave film, and subsequently the molding of a convex patterned triboreplica in which the concave film is exploited as a reusable master mold. A natureinspired TENG based on the patterned polydimethylsiloxane (PDMS) paired with flat aluminum (Al) can generate a relatively high power density of 8.1 W m −2 even if a very small force of ≈6.5 N is applied. Moreover, the convex patterned PDMS-based TENG possesses exceptional durability and reliability over 25 000 cycles of contact-separation. Considering the significant improvements in power generation of TENG; particularly at very small force, together with cost-effectiveness and possibility of mass production, the present methodology may pave the way for large-scale blue energy harvesting and commercialization of TENGs for many practical applications.

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Most mechanical energy harvesters produce only small amounts of electrical power from extremely low‐frequency input motions and immediately stop generating electricity when mechanical kinetic energy is exhausted. Here, a steady, long‐lasting and power‐boosted triboelectric nanogenerator is reported that can efficiently harvest from extremely low‐frequency irregular motions of less than 0.1 Hz by utilizing an escapement mechanism and frequency up‐conversion device. The escapement mechanism‐based triboelectric nanogenerator (EM‐TENG) consists of a mechanical energy storage spring, escapement mechanism and a torsional resonator for regular operation and frequency up‐conversion. In addition, the micro‐patterned alternating dielectric surfaces of Nylon and polytetrafluoroethylene (PTFE) and the comb‐type rotator significantly improve the output performance of the rotational EM‐TENG, increasing the current density level approximately 4.2 times compared to flat surfaces. Under an input frequency of 0.067 Hz, the EM‐TENG produces an open circuit voltage of 320 V and a short‐circuit current density of 0.59 mA m‐2. Most importantly, the EM‐TENG can produce long‐lasting and steady output power for 110 s (22 times) under only 5 s of input motion. Therefore, the EM‐TENG might pave the way to effectively harvest energy from extremely low‐frequency motions in nature, such as human motion, structural vibration and ocean waves.

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