A Highly Sensitive and Stable rGO:MoS2-Based Chemiresistive Humidity Sensor Directly Insertable to Transformer
Md Ridwan Adib1, Yongbum Lee1, Vijay V Kondalkar2
1Department of Electrical and Computer Engineering, Ajou University, Suwon, Gyeonggi-do 16499, South Korea.
ACS Sensors
|March 17, 2021
Summary
A new humidity sensor using reduced graphene oxide and molybdenum disulfide (rGO:MoS2) shows high sensitivity and stability in both air and transformer oil. This advanced sensor is ideal for real-time monitoring of power transformer operational status.
Area of Science:
- Materials Science
- Nanotechnology
- Sensor Technology
Background:
- Reduced graphene oxide (rGO) and molybdenum disulfide (MoS2) are 2D materials with high surface area and flexibility, suitable for humidity sensing.
- Existing humidity sensors require further development for stability and real-time monitoring applications.
Purpose of the Study:
- To develop a highly sensitive and stable humidity sensor based on rGO:MoS2 for monitoring transformer insulating oil.
- To integrate the sensor with a microheater, temperature sensor, and custom electronics for real-time analysis.
Main Methods:
- Synthesized rGO:MoS2 materials using ultrasonication without additives or heating.
- Deposited materials on Ti/Pt interdigitated electrodes via drop-casting.
- Analyzed sensor performance in air and transformer oil using custom interface electronics.
Main Results:
- The rGO:MoS2 sensor demonstrated high sensitivity (0.973 kΩ/%RH in air, 1.596 kΩ/%RH in oil) and excellent linearity.
- Achieved high stability with only 0.13% inaccuracy over 400 hours in air.
- Showed stable repeatability in transformer oil within a specific RH range.
Conclusions:
- The p-n heterojunction in rGO:MoS2 contributes to significant sensing capabilities.
- The developed sensor system is a promising candidate for real-time monitoring of power transformer operational status.
