Microscopic Raman Spectroscopy for Graphene Sample Testing

Tested using a Raman microscope excited by a 532nm laser:
Samples should be placed on slides with aluminum foil.

Spray drying graphene

1. After focusing the sample with a 20X objective lens, as shown below:

2. Need to move the stage down 15 times, 100um each time (reference)

3. Acquisition parameters: integration time 20s, laser power 30mw, use 1 baseline correction
 

The test results are as follows

carbon nanotubes

1. After focusing the sample with a 20X objective lens, as shown below:

2. The stage needs to be moved down 17 times, each movement is 200um (for reference)

3. Acquisition parameters: integration time 20s, laser power 50mw, use 1 baseline correction
The test results are as follows:

Microwave reduction of graphene

1. The camera cannot image, and can only show the smallest light spot through the LED light source of the camera, that is, the focus state, and the sample must be flattened
2. Need to move the stage up 12 times, 100um each time (for reference)
3. Acquisition parameters: integration time 20s, laser power 30mw, use 1 baseline correction

Graphene
 

1. Imaging cannot be made through the observation camera, but only when the smallest light spot is displayed through the LED light source of the camera, that is, the focus state, and the sample must be flattened
2. Need to move the stage up 12 times, 100um each time (for reference)
3. Acquisition parameters: integration time 20s, laser power 20mw, use 1 baseline correction

※Remarks - the Raman signal strength that affects the test:
1. Sample state (moisture content)
2. Focused focus
3. Flatness of sample surface
4. Sample purity