We work in the field of catalysts for fuel cells and our work mainly related to chemistry but comment on a paper wants details about lattices strain calculations which is not our study scope
Dear Amani Fetohi,
These are actually two independent questions: (1) - how does lattice strain affect an XRD spectrum; (2) - how does lattice strain affect an activity of a material.
Despite I have no any information regarding the discussed material and, therefore, cannot answer the second question, I will try to answer the question (1).
In principle, if the lattice strain is uniform in certain crystallographic direction, it causes change in an appropriate d-spacing. According to Bragg's low, increase in a d-spacing causes XRD peaks' shift left (towards lower diffraction angles), and vice versa. Usually, when a crystal is tensed in certain direction (i.e. contains pressure residual stresses), the appropriate d-spacing is decreased (and all peaks are placed slightly "righter", i.e. at higher 2Thetas) than in the non-strained state, and vice versa.
A presence of non-uniform strains is usually accomplished by non-uniform stresses resulting in a peak broadening, which can be distinguished mathematically from that caused by small "zones of coherent diffraction" (namely - monocrystals) and then calculated.
I recommend you to read a classical handbook of Cullity "Basics in X-rays diffraction".
If you have any more questions, please do not hesitate to ask.
Dear Dr. Amani Fetohi
Dr. Alexander Katz-Demyanetz explains in detail the uniform and non-uniform lattice strain based on peak shifting and peak broadening, respectively. I think that this explanation will help you a lot. You can use Williamson-Hall plot to calculate the lattice strain (you need a good software). Further, you can calculate linear and planar defects from XRD pattern. Please, google the "role of lattice defects in catalytic activities".
Defects and Interfaces on PtPb Nanoplates Boost Fuel Cell Electrocatalysis
Regards
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