How to use Optosky Raman spectrometer to quickly identify graphene?

    Graphene is an excellent choice for electronic product materials. It is currently the thinnest, hardest, and strongest new type of nanomaterial with the strongest electrical and thermal conductivity. It can be used in aerospace and military high-precision fields.

    Graphene is a new material in which carbon atoms connected by sp² hybrids are closely packed into a single-layer two-dimensional honeycomb lattice structure. It has excellent optical, electrical, and mechanical properties, and has important application prospects in materials science, micro-nano processing, energy, biomedicine, and drug delivery. It is considered a revolutionary material in the future.

What are the unique advantages of Raman spectroscopy for graphene detection?

    Since the discovery of graphene, Raman spectroscopy has become a most important experimental method in the field of graphene research. 
Raman spectroscopy is an important technical means to quickly and losslessly characterize the crystal structure of materials, electronic energy band structure, phonon energy dispersion and electron-phonon coupling. 
    Raman spectroscopy has unique advantages in the characterization of the number of layers of graphene. The perfect Raman peak is a simple and effective method to determine the single-layer graphene, and the multi-layer graphene is Raman due to the splitting of the electronic band structure. The peak can be fitted as a superposition of multiple Lorentz peaks, and the Raman peak is closely related to the electronic band structure of graphene. Therefore, Raman spectroscopy is an effective method to determine the doping type and doping concentration of graphene.

Raman spectroscopy is based on the whole process of graphene solution measurement

According to customer requirements, test samples

• Test object: Graphene solution;
• Test purpose: to test the Raman spectrum of graphene solution under certain conditions;
• Test tool: Optosky handheld Raman ATR6600 and Miniature Raman microscope  ATR8300-532/633;

• Detection process:

  Transfer the graphene solution from the plastic reagent tube to the glass sample bottle, and try to test with a handheld Raman ATR6600;

  Use a dropper to suck the first drop of the graphene solution onto the substrate, and use ATR8300-633 to test when trying to liquid state;

  After the graphene solution is dried, test it again with ATR8300-633 and ATR8300-532.

Use ATR6600 for graphene solution test: excitation time 1000ms, laser power 30mw

Figure 1. Handheld Raman ATR6600 graphene solution Raman spectrum

Analysis of test results:

From the Raman spectrum tested by ATR6600, it can be seen that the characteristic peak is at a wavelength of 1300cm-1, with an intensity of about 1000; 1600cm-1, with an intensity of about 750.  The distinguishing characteristic signal is obvious, and it can be judged as graphene.

Use ATR8300-633 to test before and after graphene solution drying

1. Graphene solution, excitation time 10000ms, excitation power 28mw, no baseline correction.

Figure 2. Miniature Raman Microscope ATR8300-633 graphene solution Raman spectrum

2. Graphene sample after drying, excitation time 10000ms, excitation power 28mw, no baseline correction

Test result analysis:

   It can be seen that the Raman spectrum result of this test has obvious distinguishing characteristic signals in the 1350cm-1 and 1600cm-1 bands, and the intensity is about one thousand or nine hundred, whether it is in liquid or solid state below, the test results are similar, with little impact and no difference. The test results are reliable and can be judged as graphene.

Figure 3. Miniature Raman Microscope ATR8300 of ATR8300-633 graphene after drying

Test result analysis:

   It can be seen that the Raman spectrum result of this test has obvious distinguishing characteristic signals in the 1350cm-1 and 1600cm-1 bands, and the intensity is about one thousand or nine hundred, whether it is in liquid or solid state. 
Below, the test results are similar, the impact is not big, there is no difference, the test results are reliable, and it can be judged as graphene

Test after drying graphene solution with ATR8300-532

Sample graphene after drying Excitation time 10000ms Excitation power 30mw Baseline correction.

Figure 4. Miniature Raman Microscope ATR8300-532 graphene solution Raman spectrum

Test result analysis:

    It can be seen that the Raman spectrogram result of this test has obvious distinguishing characteristic signals in the 1343cm-1 and 1600cm-1 bands. The intensity is up to one thousand five or one thousand two. The test result is reliable and can be judged. 
For graphene.

    In the research of graphene Raman spectroscopy, Raman spectroscopy has certain advantages in measuring graphene. It can obtain the Raman spectrum of graphene without damage and fast, and with few interference factors, so as to achieve rapid identification. 
    The research of graphene Raman spectroscopy still has a lot of room for research and development. If you are interested in and have experience in the research of graphene Raman spectroscopy, welcome to discuss and learn together.