No references needed, they are two different techniques. Training, applicability and Sample preparation alone accounts for many differences.

The first method is good for minor and trace elements, the second - for major elements. What type of difference was observed?

Vladimir Dusevich It has shown a very high content of S with EDX anlysis, also the Mn content by EDX method in sample was higher than ICP-AES

Dear Rakesh Kumar , as stated before by William Letter and Vladimir Dusevich these are different methods and have different element sensitivity.

Perhaps the differences you observed are caused by that reason, but probably it could have something to do with the way these two methods are applied to samples.

ICP AES give you information about the whole sample, since this is prepared as a solution that is sprayed into the plasma plume for analysis.

SEM EDX however, provides information from a solid sample, and that information is quite local, both in the depth direction and the analyzed area because the electron beam is focused in a tiny area of your sample and the electrons only penetrates till certain depth (depending on the electron beam energy and the sort of materials forming your sample).

Imagine that your sample is heterogeneous, for the sake of simplicity let it be formed by just 2 components (A,B) in realtion 1:1, distributed in grains of say 1 mm3 they are both soluble and can therefore a representative aliquot of your sample can be sent to the ICP-AES, which retrieves the real composition of your sample (A1B1) (remember the sampling is key). Now, you analyze another sample fraction by SEM EDX, if the beam is focused on a grain of component A, then you get the composition of this component (A), but may be some of B too, because some electrons were able to reach some grain of B, so you can get something like A0.8 B0.2, that clearly is different from the real one A1B1.

You could also hit a grain of B with reverse results. Even if you take enough EDX data from different regions on the surface of your sample, they could not be representative, imagine A and B are forming layers, they still are in 1:1 proportion, but an EDX analysis of the surface would give you mainly the information about the external layer, or just it if the layer thickness is enough to avoid the electron beam reach the second layer.

Hope this helps. Good luck with your work.

Dear Rakesh Kumar , you are welcome. Glad to help.

Regards.

First method for multielemental analysis and second method for singnificant of marphology

Reference

https://doi.org/10.1155/2014/891928