Raman spectroscopy is the gold standard for characterizing two-dimensional materials like graphene. However, it’s relatively slow and the laser light can damage some materials. Scientists from University of Twente have created a method that’s fifty times faster and more ‘gentle’ to sensitive materials, by adding a smart algorithm to the detection. The research is presented in National Science Review.
Graphene is always raising high expectations, as a strong, ultrathin, two-dimensional material that could also be the basis for new components in information technology. The question is if Raman characterization still remains the best option or if there are better alternatives. UT researchers Sachin Nair and Jun Gao keep Raman spectroscopy as a starting point but managed to improve the speed drastically. Not by changing the technique itself, but by adding an algorithm.
The algorithm, called Principal Component Analysis (PCA), is used in the world of signal processing to improve the signal-to-noise ratio. Combined with a detector called an electron-multiplying charge-coupled device, this accounts for measuring fifty times faster. Also, the intensity of the laser can be lowered, which decreases sample damage.
The improved Raman technique can, apart from graphene, be used for other two-dimensional materials like germanene, silicene, molybdenum disulfide, tungsten disulfide and boron nitride. Use of the algorithm isn’t limited to Raman spectroscopy; techniques like atomic force microscopy could also benefit from it.