Development of nanoparticle bulk morphology analysis: a multidomain XRD approach

FCC nanocrystals synthesized via chemical routes commonly are multitwinned with nanodomains of perfect fcc. Article provides tool to quantify the effect: determine size of the average nanodomain and their average number.

Polish National Science Centre (NCN), grant number 2018/29/B/ST4/00710 DESY synchrotron proposal number: I–20210744 EC

The appearance of twin/stacking faults in nanoparticles creates strains affecting the catalytic, optical, and electrical properties of nanomaterials. Currently, there is a lack of experimental tools for a numeric characterization of these defects in samples. Therefore, many structure–property correlations are poorly understood. Here, we report the exploration of the twinning effect on the XRD pattern and its practical application. We developed a new approach focused on the special mutual orientation of periodic fcc seg- ments, domains. Using computational simulations, we found that the more domains, the smaller the height ratio of 220 to 111 diffraction peaks. Knowing this correlation, we performed the XRD bulk mor- phology and size analysis of Au and AuPt samples. The obtained results were compared with the results of TEM and SAXS analyses. In a broader context, our multidomain XRD method is a simple alternative to TEM which enables unraveling the structure–property correlations in NP studies.