Highly Sensitive Low-Frequency Acoustic Sensor Based on Functionalized Graphene Oxide

Area of Science:

• Materials Science
• Acoustic Engineering
• Nanotechnology

Background:

• Miniaturized low-frequency acoustic sensors are vital for geological monitoring and aerospace exploration.
• Traditional nanoscale sensing films lack mechanical robustness, limiting sensor performance.
• There is a need for highly sensitive, robust, and compact low-frequency acoustic sensors.

Purpose of the Study:

• To propose a novel functionalized graphene oxide (GO)-based Fabry-Perot (FP) low-frequency acoustic sensor.
• To enhance sensor sensitivity, mechanical robustness, and reduce minimum detectable pressure (MDP).
• To demonstrate superior performance compared to existing low-frequency acoustic sensors.

Main Methods:

• Functionalized graphene oxide (GO) synthesized via reaction with dodecylamine.
• Uniform GO films prepared using a self-assembly method.
• Fabry-Perot (FP) cavity integrated for acoustic sensing.

Main Results:

• Achieved a high sensitivity of -91.92 dB re 1 rad/µPa at 10-200 Hz with low fluctuation (0.4 dB).
• Demonstrated a sensitivity approximately 5.6 times higher than non-functionalized GO sensors.
• Recorded a low MDP of 0.333 µPa/Hz^1/2 @20 Hz and a high SNR of 136.34 dB.

Conclusions:

• The functionalized GO-based FP sensor offers compact size, electromagnetic interference resistance, high sensitivity, and low MDP.
• This sensor design outperforms conventional metal or polymer-based low-frequency sensors.
• The developed sensor is suitable for demanding applications requiring precise low-frequency acoustic detection.