Highly Responsive and Robust Micro-/Nano-Textured Self-Powered Triboelectric Humidity Sensor

To overcome the reliance on external power for humidity sensors, this work demonstrates a self-powered triboelectric humidity sensor (TEHS) based on contact electrification between hydrophobic micro-/nano-textured PDMS and nano-textured aluminum films. The sensor produces an electrical output related to the relative humidity level, with ultrafast response and relaxation times.

• Development of a self-powered triboelectric humidity sensor (TEHS).
• Record-fast response (2.2 s) and relaxation (1.9 s) times.
• Good linearity over a wide humidity detection range (10–90% RH).
• Superior performance in response and relaxation times compared to a commercial humidity sensor.

A TEHS was fabricated using hydrophobic micro-/nano-textured PDMS and nano-textured aluminum films. The device's electrical output was measured in response to external mechanical force under varying relative humidity levels. Its performance was compared to a battery-powered commercial sensor.

The TEHS showed a record-fast response and relaxation time and good linearity over a wide humidity range. It exhibited highly reliable and stable output over thousands of cycles. The self-powered sensor significantly outperformed a commercial sensor in terms of response and relaxation times.