Eco-Friendly Disposable WS2 Paper Sensor for Sub-ppm NO2 Detection at Room Temperature
Daniel Matatagui1, Carlos Cruz1, Felix Carrascoso2
1Grupo de Tecnología de Sensores Avanzados (SENSAVAN), Instituto de Tecnologías Físicas y de la Información (ITEFI), CSIC, 28006 Madrid, Spain.
Nanomaterials (Basel, Switzerland)
|April 12, 2022
Summary
We created eco-friendly, disposable gas sensors using paper and tungsten disulfide (WS2) nanoplatelets. These highly sensitive sensors detect nitrogen dioxide (NO2) at room temperature, offering a low-cost solution for environmental monitoring.
Area of Science:
- Materials Science
- Environmental Science
- Sensor Technology
Background:
- Developing low-cost, disposable, and environmentally friendly sensors is crucial for widespread gas detection.
- Traditional sensors often rely on toxic materials or require elevated temperatures for operation.
- There is a need for highly sensitive and selective sensors for real-time environmental monitoring.
Purpose of the Study:
- To develop inexpensive and disposable gas sensors with a low environmental footprint.
- To utilize biodegradable paper as a substrate with safe, nontoxic electronic materials.
- To demonstrate the effectiveness of tungsten disulfide (WS2) nanoplatelets as a sensing layer for nitrogen dioxide (NO2).
Main Methods:
- Fabrication of gas sensors using abrasion-induced deposited WS2 nanoplatelets on a biodegradable paper substrate.
- Investigating sensor performance, specifically electrical resistance changes upon exposure to NO2 at room temperature.
- Evaluating sensor selectivity against interfering gases like ammonia (NH3) and carbon monoxide (CO).
- Assessing sensor response under varying humidity conditions.
Main Results:
- The developed WS2-on-paper sensors exhibited high sensitivity and selectivity towards NO2 at room temperature.
- A significant decrease in electrical resistance was observed upon NO2 adsorption (~42% for 0.8 ppm), with a detection limit around 2 ppb.
- The sensor showed minimal response to NH3 and CO, demonstrating high selectivity.
- Improved sensor response was noted under humid conditions.
Conclusions:
- The paper-based WS2 nanoplatelet sensors are a promising, high-performance, low-cost, and portable solution for continuous on-site NO2 monitoring.
- The use of biodegradable materials and room temperature operation significantly reduces the environmental footprint.
- These sensors offer a viable alternative for environmental and safety applications requiring real-time gas detection.
