Enhanced ammonia sensing using Pt-decorated single-crystalline SnO₂ nanowires prepared by sputtering

Area of Science:

• Materials Science
• Chemical Engineering
• Sensor Technology

Background:

• Ammonia (NH3) is a toxic gas prevalent in industrial processes.
• High-performance sensors are crucial for effective NH3 detection.
• Tin dioxide (SnO2) is a promising material for gas sensing applications.

Purpose of the Study:

• To develop a highly sensitive ammonia gas sensor.
• To investigate the effect of platinum (Pt) coating on SnO2 nanowire gas-sensing performance.
• To understand the mechanism behind enhanced NH3 detection.

Main Methods:

• Synthesized single-crystal SnO2 nanowires using chemical vapor deposition (CVD).
• Coated SnO2 nanowires with varying thicknesses of Pt using sputtering.
• Tested the gas-sensing performance of Pt-coated SnO2 nanowires towards NH3.

Main Results:

• Pt-coated SnO2 nanowires exhibited significantly enhanced NH3 sensing performance compared to bare SnO2.
• A 5 nm Pt-coated SnO2 nanowire sensor showed a response of 19.98 to 500 ppm NH3, a 19-fold increase.
• The sensor demonstrated fast response/recovery times and excellent selectivity against interfering gases.

Conclusions:

• Platinum coating dramatically improves the ammonia gas-sensing capabilities of SnO2 nanowires.
• The developed Pt-SnO2 nanowire sensor is a high-performance solution for NH3 detection.
• A mechanism for the enhanced sensitivity was proposed and investigated.