Despite the rapid development of various wearable generators to harvest energy from human activity, they are limited to single or intermittent power generation. Here, stretchable and washable energy harvesting fabric is reported, which enables biomechanical and biochemical generation through co‐weaving triboelectric generator (TEG) and perspiration electric generator (PEG)‐based fibers. The two energy harvesting approaches can work individually or simultaneously, thereby combating humidity and increasing the electrical output. The maximum output power density of TEG‐ and PEG‐based fibers can achieve 166 and 5.4 µW cm−2, respectively. The woven‐structured patch‐type energy harvester is conformable with clothing. It can harvest energy from human movements and sweat to drive the wearable Internet of Things (IoT) without charging systems. This synergistic and complementary energy harvester can provide a viable standalone power source relying solely on human activity for wearable electronics.

Piezoelectric Energy Harvester A piezoelectric energy harvester (PEH) that converts unused ambient vibration energy into useful electricity can alleviate issues related to the battery maintenance and power line installation of IoT sensors. To maximize the harvesting power, the resonance frequency of the PEH should match the dominant frequency of the ambient vibrations. In article number 2205179 , Kyung‐Hoon Cho, Hyun‐Cheol Song, and co‐workers report a novel autonomous resonance‐tuning (ART) PEH that autonomously adjusts its resonance frequency in accordance with ambient vibrations without any external assistance or human intervention. The PEH design methodology to implement the ART function is provided along with its real‐world validation under low‐frequency (<100 Hz) complex vibrations in which the acceleration and frequency change simultaneously.

An innovative autonomous resonance‐tuning (ART) energy harvester is reported that utilizes adaptive clamping systems driven by intrinsic mechanical mechanisms without outsourcing additional energy. The adaptive clamping system modulates the natural frequency of the harvester's main beam (MB) by adjusting the clamping position of the MB. The pulling force induced by the resonance vibration of the tuning beam (TB) provides the driving force for operating the adaptive clamp. The ART mechanism is possible by matching the natural frequencies of the TB and clamped MB. Detailed evaluations are conducted on the optimization of the adaptive clamp tolerance and TB design to increase the pulling force. The energy harvester exhibits an ultrawide resonance bandwidth of over 30 Hz in the commonly accessible low vibration frequency range (<100 Hz) owing to the ART function. The practical feasibility is demonstrated by evaluating the ART performance under both frequency and acceleration‐variant conditions and powering a location tracking sensor.

Dual Energy Harvesting Fabrics In article number 2300530, Ji‐Soo Jang, Hyun‐Cheol Song, and co‐workers demonstrate a dual energy harvesting fabric that enables bio‐physicochemical generation through the co‐weaving of triboelectric generator‐ and perspiration electric generator‐based fibers. The fabric harvests energy not only from human movement but also from sweat to power wearable IoT devices and exhibits remarkable washing durability.