New ultra-sensitive ammonia sensor can enable portable, self-powered, wearable devices to prevent toxic gas exposure

Scientists at the Centre for Nano and Soft Matter Sciences (CeNS), Bengaluru, under the Department of Science and Technology have created a hybrid vanadium oxide‑vanadium sulfide (VOx/VS2) ammonia sensor that detects ammonia as low as 319 ppb at room temperature. The sensor shows high selectivity, stable operation over ten weeks, and works across a wide concentration range. Prototypes include portable threshold‑triggered monitors, self‑powered devices powered by a flexible piezoelectric nanogenerator, and wearable versions on polymer, paper and textile substrates. These devices can alert users to unsafe ammonia levels in industrial, laboratory and agricultural settings, enabling real‑time safety monitoring without external power sources.