Hi Neeran,

My experiences with XRD and nanoparticles that I create from CO2 + reducing agent detonations has taught me several important things that I would like to share. First, the smaller a particle, the wider and flatter the peaks that are generated. Second, if you are not working with reasonably pure materials or combinations of pure materials, XRD doesn't work as well as expected.

Also, consider if my process creates something new. XRD will never tell me what it is if the machine operator only matches up peaks that are provided in a database of known materials. The typical attitude from the XRD operators I've worked with is: "Let's see what stuff you made by comparing your results with tests that have already been done on stuff that's been made before." There is the expectation that new things are way less possible than things that have already been done.

So, therein lies the challenge: to determine the properties of something through a form of observation that we think should tell us one thing but instead tells us something else because of the properties we are trying to determine while we limit ourselves to a fixed number of options to sift through. This is a tricky place to go when your objective is to find the truth. What if your nanoparticles are made of a new material or posses a unique structure that has never previously been achieved? XRD might miss this depending on who is doing the test rather than whether the test is reliable.

XRD, or any investigative tool that you employ, works as perfectly as your ability to understand how the tool works and how using the tool tells you about what is there regardless of what it is. To me, XRD is an amazing tool because it provides feedback from materials that enables a deeper understanding of its lattice structure. Your question reveals that you can potentially benefit from researching how XRD works in relation to the properties of the materials you are examining with it.

Good luck - If you have easy and affordable access to XRD I recommend that you get a sample analyzed and ask lots of questions of the XRD operator. I even recommend taking them out for a coffee and learn, learn, learn.

Can u explain more clearly about your question.

XRD provides you with a lot information. However, if you are only looking to very superficial diagnostic information, you should be mainly worried about peak broadening due to particle size.

The broadened peaks could overlap with peaks from different phases. Assuming you control all other experimental parameters which effect peak-broadening. Look at an alternative technique to confirm the phase or stoichiometry.

Thanks for answer

Hi Neeran,

My experiences with XRD and nanoparticles that I create from CO2 + reducing agent detonations has taught me several important things that I would like to share. First, the smaller a particle, the wider and flatter the peaks that are generated. Second, if you are not working with reasonably pure materials or combinations of pure materials, XRD doesn't work as well as expected.

Also, consider if my process creates something new. XRD will never tell me what it is if the machine operator only matches up peaks that are provided in a database of known materials. The typical attitude from the XRD operators I've worked with is: "Let's see what stuff you made by comparing your results with tests that have already been done on stuff that's been made before." There is the expectation that new things are way less possible than things that have already been done.

So, therein lies the challenge: to determine the properties of something through a form of observation that we think should tell us one thing but instead tells us something else because of the properties we are trying to determine while we limit ourselves to a fixed number of options to sift through. This is a tricky place to go when your objective is to find the truth. What if your nanoparticles are made of a new material or posses a unique structure that has never previously been achieved? XRD might miss this depending on who is doing the test rather than whether the test is reliable.

XRD, or any investigative tool that you employ, works as perfectly as your ability to understand how the tool works and how using the tool tells you about what is there regardless of what it is. To me, XRD is an amazing tool because it provides feedback from materials that enables a deeper understanding of its lattice structure. Your question reveals that you can potentially benefit from researching how XRD works in relation to the properties of the materials you are examining with it.

Good luck - If you have easy and affordable access to XRD I recommend that you get a sample analyzed and ask lots of questions of the XRD operator. I even recommend taking them out for a coffee and learn, learn, learn.

Thanks Sr..for all

First, XRD tells about the phase purity of the prepared sample, i.e., single- or multi-phase sample. Second, it tells quite well about the crystallite size and lattice parameter. Third, it gives reasonable information abut the strain in the sample though using Williamson-Hall method.

Thanks Dr.Adel_Wahba

One can calculate crystallite size from powder XRD data; a crystallite is generally composed of several particles. Hence, one can not get a single particle size exactly from XRD data;one can only get some idea of particle size of the powder.

You can use standard data, i.e JCPDS to identify your crystal structure for known structure or if you are not known about the crystal structure (orientation). Also you can determine the crystal size When using the Debye-Scherrer equation:

Particle Size = (0.9 x λ)/ (d cosθ)

λ = 1.54060 Å (in the case of CuKa1) so, 0.9 x λ = 1.38654

Θ = 2θ/2 (in the example = 20/2)

d = the full width at half maximum intensity of the peak (in Rad) – you can calculate it using Origin software.

To convert from angle to rad

Rad = (22 x angle) / (7 x 180) = angle x 0.01746

Example: if d = 0.5 angle (θ)

= (22 x 0.5)/ (7x 180) = 0.00873 rad

best of luck

My experience using XRD with nanoparticles refers to the structural characterisation, considering both the mesophase and sub-crystalline organization of lipids in NPs. XRD is a useful technique to obtain informations about phase transitions when you add drugs or antioxidants in the NP formulation, together with the stability of the phase assumed by lipids (considering for example if the peak is broad or narrow). I suggest to you a Chapter published by Elisabetta Esposito et al., i will send to you a copy if you want. In our work the structural characterisation using XRD is fundamental.

Thanks dear Federica for all

grain size,