Heteroatom-engineered black phosphorus nanosheets with ambient stability for selective NO₂/NO detection

Black phosphorus (BP) is a highly promising two-dimensional semiconductor for ultrasensitive gas detection, yet its rapid degradation under ambient conditions still limits device reliability. Herein, we present a heteroatom-engineering strategy employing Te and Sb dopants to regulate both the electronic structure and surface oxidation dynamics of BP nanosheets (BPNSs). The Sb-doped BPNSs exhibit superior long-term stability (>20 days) and selective NO₂/NO detection at room temperature, outperforming pristine and Te-doped counterparts. Combined XPS depth profiling and cross-sectional HRTEM directly reveal dopant-dependent oxidation inhibition and band alignment modulation. This work establishes a generalizable design principle linking heteroatom-induced band modulation to ambient durability and sensing selectivity, paving the way for low-power, long-lifetime BP-based gas sensors suitable for IoT environmental monitoring.