LAUSR

As a promising hydrogen carrier for low-carbon energy cycling, ammonia also represents the most abundant alkaline gas in the atmosphere, impacting environmental quality through diverse geophysical and chemical processes. Hence, developing NH3 sensing materials with high sensitivity and stability under self-powered operation is essential. A one-step in situ polymerization method is demonstrated to synthesize zinc oxide/graphene oxide (ZnO/GO) nanocomposites, serving as a gas-sensitive film for ammonia sensing and as high-performance electrode materials in supercapacitors, simultaneously. For the supercapacitor, the specific capacitance of 131 F g-1 at 1 A g-1 is achieved. The ammonia sensor featured a low detection limit (0.1 ppm) and fast response/recovery time (17 s/26 s @ 10 ppm NH3), surpassing standards set by the US Occupational Safety and Health Administration (50 ppm), while outperforming commercial NH3 gas sensors. By integrating the sensor into a detection instrument for fixed-point monitoring, the response relative standard deviation of below 1% over 210 days of continuous testing is achieved. In addition, a wearable contact-separated TENG is developed to harvest mechanical energy from a contact-separation setup that mimicked human footsteps, achieving a maximum output power of 4.1 mW to directly drive the ammonia gas sensor. The multi-scenario applications enhanced the spatial coverage and operational flexibility of NH3 concentration monitoring.