In this study correlative microscopy techniques are used to analyze materials at a micro and nanoscale level. Specifically, the study combines Raman and EDS analytics with SEM and LM imaging to obtain a comprehensive understanding of the chemical and structural properties of materials. The methodology used to integrate these techniques is using a software-based solution including an image-based alignment step. Instead of using holders decorated with fiducials, like in the ‘Shuttle and Find’ based workflow [1], here one can use any characteristic landmarks of the sample. As a result, for a battery sample, we can demonstrate the benefit of combining multiple analytical techniques, to gain a more complete understanding of material properties.

The sample workspace is used to align images from different microscope. It enables navigation on the SEM using the LM and Raman maps from the Raman microscope. The ‘ZEN Connect’ software module (Zeiss Microscopy) is used to organize and visualize different microscopy images and data from the same sample in context. For sample-centric analysis, ZEN Connect workflows enable you to get from a quick overview image to advanced imaging. The alignment step consists of 3 landmarks imaged with the Raman microscope are reimaged with the SEM. The workflow continues with re-finding the position for correlative SEM imaging and EDS analysis. The sample workspace is used to control the stage by image-based navigation.

The advantage of combining Raman with SEM often lies in using the better resolution of the SEM to reveal details of the microstructure. For the anode particles the layered structure of the graphite is resolved clearly in the SEM, combined with the chemical information of the Raman maps for different carbon modifications. In addition, the EDS signal can be used to support the Raman chemical data with additional elemental mapping. This is useful for detailed understanding and interpretation of the Raman spectra and maps.

References

[1] Raman analytics was conducted by Thomas Meyer, WITec GmbH

[2] Blazquez-Llorca, L., et al., 2015. J. Microsc. 259, 129–136