Exhalation‐Driven Mask‐Valve‐Integrated Triboelectric Nanogenerator with Amplified Output Current

Respiration‐driven airflow‐type triboelectric nanogenerators (TENGs) exhibit limitations in reliable integration into masks, avoiding direct exposure to respiratory moisture and achieving high output performance. An exhalation‐driven mask‐valve‐integrated TENG (EM‐TENG) is proposed in this study. EM‐TENG is entirely integrated into the interior of the mask valve and generates a high output current and power of 170 mA and 4.2 W (peak frequency: 60 Hz) with a compact size (3.87 cm 3 ) via charge separation and a direct electron flow mechanism. An EM‐TENG is unaffected by the moisture in human exhalation, ensuring that it maintains the original output for long‐term breathing (1,000,000 rotations). EM‐TENG features a blade rotation design that is mechanically and electrically optimized and can operate even at a human exhalation speed of 4 m s −1 and for maximized output in a small device size. Furthermore, an EM‐TENG can continuously power 20 light‐emitting diodes and a 5 W commercial lamp and operate a commercial thermohygrometer sensor after charging the capacitor. This device can potentially be used as a sustainable power source for commercial sensors and monitoring devices in everyday life and industrial environments in which wearing a mask is required.