Periodic Reporting for period 1 - POLARSENSE (POLARSENSE: Polaritonic compact gas sensor demonstrator)
Periodo di rendicontazione: 2023-07-01 al 2024-12-31
Gas sensors play a key role in applications that are involved in our daily lives. The main function of these sensors consists of monitoring the amount of gases in a particular environment. This could enable the prediction and prevention of dangerous situations, such as avoiding breathing toxic gases or particles in houses or offices. In industrial settings it is necessary to monitor the presence of combustible gases that can also lead to undesired situations. Another significant field is the diagnosis of medical conditions through the use of breath analyzers. For all these applications, the gas sensors have to be integrated into portable and wireless devices for sensing, processing, and remotely communicating data across a network.
The goal of POLARSENSE is to develop a gas sensor demonstrator that enables the miniaturization and integration of these sensors in portable devices for Internet of Things (IoT) applications. In order to accomplish this goal, the gas sensor should fulfill several requirements such as being compatible with silicon technology, operating at ambient conditions with low power consumption, exhibiting a high sensitivity (low limit of detection), presenting high selectivity to gases, and demonstrating a high detection speed.
Therefore, POLARSENSE has 4 main objectives. The first one consists of determining the design of the electro-polaritonic demonstrator. This is based on the results of simulations that predict its optimum performance. The second objective is fulfilled by fabricating and characterizing the electro-polaritonic gas sensor demonstrator. The third objective involves building a broadband setup for the infrared range with a fast acquisition time and low-noise electronics. Finally, the fourth objective comprises the detection of volatile organic compounds with a high sensitivity and selectivity.
The goal of POLARSENSE is to develop a gas sensor demonstrator that enables the miniaturization and integration of these sensors in portable devices for Internet of Things (IoT) applications. In order to accomplish this goal, the gas sensor should fulfill several requirements such as being compatible with silicon technology, operating at ambient conditions with low power consumption, exhibiting a high sensitivity (low limit of detection), presenting high selectivity to gases, and demonstrating a high detection speed.
Therefore, POLARSENSE has 4 main objectives. The first one consists of determining the design of the electro-polaritonic demonstrator. This is based on the results of simulations that predict its optimum performance. The second objective is fulfilled by fabricating and characterizing the electro-polaritonic gas sensor demonstrator. The third objective involves building a broadband setup for the infrared range with a fast acquisition time and low-noise electronics. Finally, the fourth objective comprises the detection of volatile organic compounds with a high sensitivity and selectivity.
One of the main activities of POLARSENSE consisted of designing the electro-polaritonic gas sensors based on optical and thermoelectric simulations. These ensure that their performance is optimal for detecting gases, whose vibrational modes rely on the mid-IR range that spectrally overlaps with the polaritonic resonances that we carefully engineer. We develop two main sensing platforms based on different architectures. We have successfully reproduced the mentioned platforms by fabricating and measuring 5 devices. We also compare the performance of the devices with scalable materials with respect to the ones made with flakes. A broadband infrared setup was built to perform spectroscopy, including the wavelength range between 1 to 20 µm. This setup is highly compact, non-sensitive to mechanical vibrations and optimal for its integration in future prototypes. We have tested the gas sensing performance of the developed platforms by detecting multiple volatile organic compounds such as acetone, 2-isopropanol, and ethylene with a sub-ppm sensitivity. We have shown the tunability of the spectral response of these sensors by changing the graphene doping. The experimental results are in very good agreement with our theoretical model, thus enabling the prediction of the performance of the sensors for further improvements. We have studied their behavior under mixture of gases for different concentrations. Finally, we have determined the gas detection speed, which is below 1 second.
The developed gas sensing platforms present unique capabilities by showing them in one single platform, such as high-speed detection with high sensitivity and selectivity, compatibility with silicon technology, reusability and operation under ambient conditions, etc. This performance has not been demonstrated in commercially available gas sensors, which highlights the potential of this platform. Further developments will consist of producing a compact and portable prototype to test in several relevant environments. Partnering with key players in the gas sensing field is crucial to ensure the development of this technology.