Humidity impedimetric sensor based on vanadium pentoxide xerogel modified screen-printed graphite electrochemical
Maria G Trachioti1, Mamas I Prodromidis1
1Department of Chemistry, University of Ioannina, 45 110, Ioannina, Greece.
Talanta
|May 28, 2020
Summary
A new vanadium pentoxide xerogel (VPX) humidity sensor was developed on a screen-printed electrochemical cell. This VPX sensor offers high sensitivity and fast response for real-time relative humidity monitoring.
Area of Science:
- Materials Science
- Electrochemistry
- Sensor Technology
Background:
- Development of advanced materials for environmental monitoring.
- Need for sensitive and stable relative humidity sensors.
Purpose of the Study:
- To design and characterize a novel humidity sensor.
- To utilize vanadium pentoxide xerogel (VPX) on a screen-printed electrochemical cell (SPC) for relative humidity (RH%) sensing.
Main Methods:
- Fabrication of VPX thin films on SPC.
- Characterization using scanning electron microscopy (SEM), ATR-infrared spectroscopy, and electrochemical impedance spectroscopy (EIS).
- Performance evaluation across a wide RH range (10-93%).
Main Results:
- VPX/SPC sensor demonstrated high sensitivity (190-500 Ohm/RH%) and a wide RH detection range.
- Achieved a sensor response of 93% with low hysteresis and good storage stability.
- Fast response (52 s) and recovery (21 s) times were recorded.
- EIS data provided insights into the conduction mechanism and interface properties.
Conclusions:
- The VPX-based sensor is suitable for on-site and real-time relative humidity monitoring.
- The developed sensor exhibits promising performance characteristics for ambient condition applications.
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