Phys.og January 6, 2023
Despite intensive research and rapid progress in self-powered gas devices, most reported devices, specifically NO2 sensors for air pollution monitoring, have limited sensitivity, selectivity, and scalability. Researchers in Australia have demonstrated a photovoltaic self-powered NO2 sensor based on axial p–i–n homojunction InP nanowire (NW) arrays, that overcame these limitations. The device was designed by numerical simulation for insights into sensing mechanisms and performance enhancement. Without a power source, the InP NW sensor achieved an 84% sensing response to 1 ppm NO2 and recorded a limit of detection down to the sub-ppb level, with little dependence on the incident light intensity, even under <5% of 1 sun illumination. The sensor was integrated into a commercial microchip interface to evaluate its performance in the context of dynamic environmental monitoring of motor vehicle exhaust. The results showed that compound semiconductor nanowires can form promising self-powered sensing platforms suitable for future mega-scale IoT systems…read more. TECHNICAL ARTICLEÂ
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