BET is the most common technique for SSA measurement - SEM is providing only a 2-D representation of a 3-D particle (but of course this information is extremely valuable). I concur with Sebastian.  Maybe the reviewer is thinking of the Scherrer XRDLB technique for crystallite evaluation - the line broadening (excluding strain) gives some indication of size in the 1 - 100 nm region.  The SSA is related to the Sauter Mean Diameter by the simple relation SSA = 6/D[3,2] (where SSA would be area/volume say m2/cm3 - with density in cm3/g one can then get a predicted SSA in the appropriate units from the Scherrer 'size'.  Lots of issues I could see with this but....

Dear Dr. Aditya... Usually SSA measurements are done using SEM. For amorhous materials, you have a lot of alternate measurements (Blaine's Method; BET; Mehtylene Blue Method etc.;) I attempted Surface Area determination relying on SEM for quantifying the retention of various metal ions on cohesive soils, but in vain.

I believe you are looking to quantify something on glass matrix relying on SSA, so may be you can capture the pattern better than me. For me the charring on the soil samples was so high that virtually nothing was visible... !!!

Dear Aditya, 

Maybe the reviewer had in mind the crystallite size? Not the exact area?

That would make sense if you are growing crystals inside the glass (at least I suppoese), I don't know the full paper, so maybe you had it included.

Best regards,

Sebastian

BET is the most common technique for SSA measurement - SEM is providing only a 2-D representation of a 3-D particle (but of course this information is extremely valuable). I concur with Sebastian.  Maybe the reviewer is thinking of the Scherrer XRDLB technique for crystallite evaluation - the line broadening (excluding strain) gives some indication of size in the 1 - 100 nm region.  The SSA is related to the Sauter Mean Diameter by the simple relation SSA = 6/D[3,2] (where SSA would be area/volume say m2/cm3 - with density in cm3/g one can then get a predicted SSA in the appropriate units from the Scherrer 'size'.  Lots of issues I could see with this but....

Dear Alan, 

I have learnt sth valuable from your answer so thank you!

Answering leads to learning, true value of RG. Hope it will develop in this direction.

Best regards,

Sebastian

Thank you, Sebastian.  You are too kind.

Dear Dr. Rawle and Dr. Molin,

I had no idea that SSA measurement could be attempted the way you just described. Thanks a lot for your answer. Though I am pretty sure that the actual surface area was the reviewer's intentions as I have primarily reported the sample for catalysis and the crystallite size is already mentioned.

I will look into it anyways.

Regards

One very important thing to remember though is that the specific surface area calculated from the crystallite size isn't accessible surface in the same way that the SSA measured by say BET. A BET measurement gives a good idea of available surface area.  Most of the grain boundaries in the crystallite are not accessible (even though they provide potential areas of weakness or where other atoms could diffuse more rapidly than in the bulk.  Typically you'd expect a surface area calculated from the crystallite size to be significantly higher than one measured by BET.

BTW, this document on particle size basics may be of interest.

BET is the most common technique for SSA measurement.

XRD usually just use to know the crystals structures or crystalline of materials and it would be better accompanied the XRF data of material, because some material have similar peaks result in XRD result. XRD may be can use to determine the surface area with a formula like write in this old paper " http://pubs.acs.org/doi/abs/10.1021/ac60233a046 " . but the best option, more satisfy and valid  is BET,

thanks

CMIIW

Conventional XRD can not provide any surface information. However, small-angle GIXRD technology combined with XRR technology can study surface information(strain and surface structure, etc.). And you can refer to some papers.

1. DOI 10.1007/s00339-017-0795-7

2.

Article Characterization on surface and interface structure of epita...

Alan F Rawle , Could you please provide a reference (research article) in which the surface area calculated from the crystallite size is significantly higher than one measured by BET.

Regards

Ikhtiar Gul A simple search on this site (or with Google) provides all you need. For example, Table 1 in:

Article Sensors based on Ag-loaded hematite (α-Fe2O3) nanoparticles ...

The only thing additional is the mathematical link between size and surface area indicated above.

Mathematically, SSA can be calculated using formulas and both formulas yield same result

SSA=SApart/Vpart*density

S=6*10^3/Dp*density

Where SSA & S are the specific surface area, Vpart is particle volume and SApart is Surface Area,

Dp is the size (spherical shaped), and density of TiO2 (4.23 g.cm-3).

Reference article is attached with this response, hope it ll help