Low-power NO2 detection: Zn-doped Bi2S3 nanoparticles for high sensing performance at room temperature

Nitrogen dioxide (NO 2 ) permeates every compass point and every setting, making high-fidelity, low-cost sensors an urgent public-health imperative. We answer this need by incorporating zinc ions into the bismuth sulfide (Bi 2 S 3 ) lattice to enhance its NO 2 gas-sensing performance, with the resulting Zn-doped Bi 2 S 3 nanoparticles fabricated via a facile one-step hydrothermal method. Gas-sensing measurements demonstrate the 7 % Zn-doped Bi 2 S 3 achieves a room-temperature response to 4 ppm NO 2 gas molecules, which is 2.1-fold greater than the bare Bi 2 S 3 , yielding a response value of 143.5 %, along with excellent selectivity, repeatability, and long-term stability, confirming the effectiveness of Zn doping in optimizing the gas-sensing performance of Bi 2 S 3 . The boost arises from a tandem tuning of lattice structure engineering, band structure tuning, and charge transfer kinetics modulation. This paper offers a simple strategy for constructing high-performance, low-energy-consumption NO 2 sensors operating at room temperature, holding significant implications for practical environmental sensing applications.