@Shikha Sharma has asked me the following question by PM.
In order that all can benefit I reproduce it below:
'sir , i want to know that ...is it important that.. the more the broad peak , the more surface area of that particular compoud'.
@ Shikha Sharma
XRD line broadening gives an indication of crystallite size (which will be smaller than particle size; see many discussions on RG). BET measures available specific surface area including all the pores that the N2 molecule can penetrate.
In general if your system gets smaller the surface area increases as 1/x2 where x is the particle size. Thus, in very general terms, we'd expect the SSA to increase as the peaks broaden (if there's also a link between crystallite and particle size). However, we note that the Scherrer equation isn't valid at > 100 nm or so, and, below 10 nm or so, the peak broadening is so excessive and the signal so poor that it's difficult to quantify any such broadening.
Look up a paper called written by myself; this looks at a material's (barium ferrite) SSA and the corresponding particle size measurements:
Micron sized nano-materials April 2007Powder Technology 174(1):6-9
DOI: 10.1016/j.powtec.2006.10.012
I would say that they may be related to each other. Such that if you have the same material, but you produced them by different methods and you have obtained the same XRD peaks at the same Bragg peak positions but one had a broadened XRD pattern I would definitely go with a BET test for full isotherm analysis and investigate their pore size distribution via NLDFT method. It is more probable that you have smaller pores in the material with the broadened XRD patterns. Note that, it does not have to be the case all the time.
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