Neha,  I would say that EDS (in the SEM) is not particularly suitable for analysing thin films, nanomaterials or powders. For the reason that one of the main assumptions of EDS is that the sample is homogeneous within the interaction volume. Unless you use very low accelerating voltages you are not going to be able to obtain good data from thin films; these low voltages will then limit what elements you are able to analyse. The interaction volume is in the region of a few microns, depending on the voltage, so this is too great to analyse thin films. For the same reason it is not really suitable for nanomaterials, as the size of the incident beam is usually larger than the nanoparticle, and would therefore be taking information form outside the particle. For powders, EDS is only going to give qualitative results, it is very difficult to obtain any realistic quantitative data from powders. The reason is that they contain voids and these will be measured at the same time as the particle and degrade the results.

Sirajo,  Samples suitable for EDS (in the SEM) should be flat, horizontal and finely polished to remove all surface topography. Any topography in the sample will give errors. In order to image these flat surfaces it is best to use backscatter electron imaging to enhance any atomic number contrast. As mentioned above, the sample should be homogeneous within the interaction volume; at 20kV this may be around 5um, depending on the mean atomic number of the sample. So the region for analysis needs to be larger than this, in all dimensions. It may be that what is lying beneath the surface may not be same as that seen in the image. Ideally the sample should be conductive, it can have a conductive coat applied as long as this does not interfere with the elements of interest. It is possible to work uncoated in variable pressure, but the beam skirting effect will degrade the resolution of the analysis. Light elements are challenging to quantify by EDS, qualitative identification is good with a windowless detector down to Boron. If you wish to do quantitative work, it is best to use standards. This will give you non-normalised absolute semi-quant. Software is getting better, and works well enough for 'standardless' semi-quant with heavier elements up to Uranium. This will give normalised relative semi-quant. EDS is quite versatile and can be used in various modes: spot, area, line-scanning, mapping. One of the problems with EDS is that it can be very simple to operate and obtain very precise results but without understanding the limitations these results can be meaningless.

EDS is defined as energy dispersive X-ray Spectroscopy. EDS is used to confirm the composition of a material. The presence of elements along with their percentage is confirmed using EDS. EDS technique can be used in case of thin films, nanomaterials, powder etc. EDS is a type of compositional analysis.

Neha,  I would say that EDS (in the SEM) is not particularly suitable for analysing thin films, nanomaterials or powders. For the reason that one of the main assumptions of EDS is that the sample is homogeneous within the interaction volume. Unless you use very low accelerating voltages you are not going to be able to obtain good data from thin films; these low voltages will then limit what elements you are able to analyse. The interaction volume is in the region of a few microns, depending on the voltage, so this is too great to analyse thin films. For the same reason it is not really suitable for nanomaterials, as the size of the incident beam is usually larger than the nanoparticle, and would therefore be taking information form outside the particle. For powders, EDS is only going to give qualitative results, it is very difficult to obtain any realistic quantitative data from powders. The reason is that they contain voids and these will be measured at the same time as the particle and degrade the results.

Sirajo,  Samples suitable for EDS (in the SEM) should be flat, horizontal and finely polished to remove all surface topography. Any topography in the sample will give errors. In order to image these flat surfaces it is best to use backscatter electron imaging to enhance any atomic number contrast. As mentioned above, the sample should be homogeneous within the interaction volume; at 20kV this may be around 5um, depending on the mean atomic number of the sample. So the region for analysis needs to be larger than this, in all dimensions. It may be that what is lying beneath the surface may not be same as that seen in the image. Ideally the sample should be conductive, it can have a conductive coat applied as long as this does not interfere with the elements of interest. It is possible to work uncoated in variable pressure, but the beam skirting effect will degrade the resolution of the analysis. Light elements are challenging to quantify by EDS, qualitative identification is good with a windowless detector down to Boron. If you wish to do quantitative work, it is best to use standards. This will give you non-normalised absolute semi-quant. Software is getting better, and works well enough for 'standardless' semi-quant with heavier elements up to Uranium. This will give normalised relative semi-quant. EDS is quite versatile and can be used in various modes: spot, area, line-scanning, mapping. One of the problems with EDS is that it can be very simple to operate and obtain very precise results but without understanding the limitations these results can be meaningless.

Thanks Neha Desai for your explanations

Funny question.

Dumb reaction.

Do I need to say more?

Thanks @ Ian J for the respond and explanations. Vladimir Dusevich please say something and i appreciate your reaction. Can you suggest the possible way(s) on how the question should be presented and provide us with your own explanations? Thanks and waiting to hear from you

come on Vladimir, ask his question for him ;-))

Simply, EDS is done to confirm the elemental composition (especially for composites), to make sure the obtained composition is close or same as the nominal one. It is preferred for composites and alloys.