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

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Sensing

Background:

• Black phosphorus (BP) is a promising 2D semiconductor for gas detection.
• Device reliability is limited by BP's rapid degradation in ambient conditions.

Purpose of the Study:

• To develop a heteroatom-engineering strategy to improve BP stability and sensing performance.
• To investigate the effects of Te and Sb dopants on BP electronic structure and oxidation dynamics.

Main Methods:

• Synthesized Sb-doped and Te-doped black phosphorus nanosheets (BPNSs).
• Evaluated gas sensing performance for NO2 and NO at room temperature.
• Utilized X-ray photoelectron spectroscopy (XPS) depth profiling and high-resolution transmission electron microscopy (HRTEM) for analysis.

Main Results:

• Sb-doped BPNSs demonstrated superior long-term stability (>20 days) and selective NO2/NO detection.
• Doping inhibited oxidation and modulated band alignment compared to pristine and Te-doped BPNSs.
• XPS and HRTEM confirmed dopant-dependent effects on oxidation and electronic properties.

Conclusions:

• Heteroatom doping, specifically with Sb, significantly enhances the ambient stability and sensing selectivity of BPNSs.
• The study establishes a design principle linking heteroatom-induced band modulation to improved durability and sensing.
• This approach enables the development of reliable, low-power BP-based gas sensors for environmental monitoring applications.