Dear Bikash,
as Alan pointed out, the peaks (if you will get any) will be very broad due to the small size of your particles ( 3-4nm is 30 -40A and that is about only 15 to 20 atomic layers !!!.) and thus they will be very small in height. Furthermore these tiny (broad) structures are on top of a huge background of your support (bear in mind that you have only 0,5% of your material in the x-rays beam which will contribute to your 'Au-peaks').
In order to resolve your 'peaks' from the statistical noise of the background you have to wait a very long, long time; A day or even much more.......
If your nanoparticle like material is only on top of your support you may use grazing incidence XRD, so you will be more surface sensitive. Thats the only way to increase your signal to background ratio and thus reducing measurement time.
Taking advantage of the total reflection properties of your substrate you may be successfull with GIXRD in your case.
https://en.wikipedia.org/wiki/Grazing_incidence_diffraction
https://www.rigaku.com/en/products/xrd/ultima/app029
Dear Bikash,
as Alan pointed out, the peaks (if you will get any) will be very broad due to the small size of your particles ( 3-4nm is 30 -40A and that is about only 15 to 20 atomic layers !!!.) and thus they will be very small in height. Furthermore these tiny (broad) structures are on top of a huge background of your support (bear in mind that you have only 0,5% of your material in the x-rays beam which will contribute to your 'Au-peaks').
In order to resolve your 'peaks' from the statistical noise of the background you have to wait a very long, long time; A day or even much more.......
If your nanoparticle like material is only on top of your support you may use grazing incidence XRD, so you will be more surface sensitive. Thats the only way to increase your signal to background ratio and thus reducing measurement time.
Taking advantage of the total reflection properties of your substrate you may be successfull with GIXRD in your case.
https://en.wikipedia.org/wiki/Grazing_incidence_diffraction
https://www.rigaku.com/en/products/xrd/ultima/app029
Thanks Dr. Martens for the valuable answer and reference given is also very helpful.
@ Bikash Sharma In the 70's (not my 70's - which are to come, hopefully - but the 1970's) in my Ph.D work I successfully got XRD Debye-Scherrer films from nominally 5% Au on SiO2 (Davison 70 if I recall) - made by hydrazine hydrate reduction if you want to know..... Caveats: 24 hours irradiation; sizes (number mean) were typically 10 nm (we always used Ångstroms then - 100 Å) by TEM and Scherrer equation. I calculated line broadening by hand.... See attached for an old picture from my thesis (developed and printed all my pictures too; those were the days...). For some work from this see: https://doi.org/10.1016/1381-1169(96)00027-1
Nominally 5% (found ~ 4.5%) is 10 times your quoted metal loading. Sufficient to get peaks good enough for lattice parameter calculations and looking at deviations from Vegard's Rule for the alloy systems we studied (Pd-Au, Pd-Ag). However, in the nearly 50 years that have elapsed since then XRD equipment (especially) detectors and processing has advanced markedly and I would expect this to be feasible.
Thanks Dr. Alan for the valuable answer. The reference mentioned discuss the catalytic reduction of isoprene with Pd and bimetallic Pd with group 11 metal like Au and Ag supported on SiO2 and their different selectivity to the possible isomers.
It is an interesting paper to read how half hydrogenated allylic radicals get further hydrogenated and it depends on the charge on the incoming Hydrogen which is effected by the concentration of the coinage metal present in the bimetallic Pd particles.
But the article don't have any discussion regarding the XRD and the crystallite size.
@ Bikash The paper you mention did not deal with the XRD side. I've summarized that in my answers above. We also used chemisorption, XPS (ESCA), plus a bunch of other techniques (e.g. TPR, TEM) for characterization. XRD measurements for the powder were conducted in a Lindemann tube with a really old Philips Analytical instrument on a Debye Scherrer camera (I think 114.6 mm diameter) with the film removed 24 hours later.
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