Sensors made of ultra-thin nanomaterials improve the accuracy of environmental sensing by providing clear optical fingerprints to detect contaminant molecules. Traditional sensors rely on tiny peak shifts and intensity changes to detect contaminant molecules in the air, but the method is not accurate.
Identify contaminant molecules by activating the dark electron state in the sensor material and creating new visible peaks. Changes in the optical fingerprint of the sensor material demonstrate the presence of contaminant molecules.
A research team from Chalmers University of Technology in Sweden and Berlin Technical University in Germany developed an efficient sensor using transition-metal disulfides (TMDs) of atomic-level thickness. TMDs have excellent surface area to volume ratio and extremely strong light-to-material interaction, making the material very sensitive to changes in the surrounding environment.
In addition to showing excitons, TMDs can also display a variety of dark excitons whose angular or centripetal momentum is non-zero. New sensors recognize molecules by activating dark excitons in nanomaterials. Contaminants on the surface of nanomaterials interact with dark excitons and make them visible (bright), and change optical fingerprints to show the presence of contaminant molecules.
The team demonstrated that dark excitons and bright excitons in TMDs have efficient coupling, whereas non-covalently attached molecules with strong dipole moments can make dark excitons glow, creating additional peaks in the spectrum.
"This method may open up new possibilities for the detection of ambient gases," says researcher Maja Feierabend. "Our method is more stable than traditional sensors because new sensors rely on small changes in their optical properties." When light When illuminated on the sensor, the optical fingerprint of the material will be displayed.
"Our method has great potential in the field of ultra-thin, high-speed, high-efficiency, precision transducers and in the future it is hoped that in the future it will be possible to produce sensors of high sensitivity and high discrimination for environmental research." Researchers Ermin Malic Say.
The team filed a patent application for its new sensor. Next they will work with experimental physicists and chemists to prove the principle of this new chemical sensor.
The study has been published in Nature Communications.
Thermoforming packaging containers for all kinds of vegetables, including 250g, 500g, 1000g, 1500g. Suitable for cherry tomato, cucumber, pepper and other vegetables packaging.
Using PET material clamshell packaging, with good transparency, clamshell under pressure to avoid damage in the transportation of fruits and vegetables. Each quantitative packaging container is convenient for the sales and storage of fruits and vegetables. Compared with the traditional bulk sales method, the loss of fruits and vegetables packed in blister containers can be reduced by 20% - 40%.
Plastic Vegetables Clamshell,Transparent Lettuce Clamshell,Vegetable Packaging Box,Rectangular Vegetable Box With Lid
Jiangmen JiuTai Plastic Product Co.Ltd , https://www.sequoiaent.com