Insights on The Disordered Nature in Amorphous-Based Anode Materials from Electron Pair Distribution Function

In material science, the ability of structural determination at high spatial resolution is critical for understanding their properties. Over the years, traditional X-ray and electron diffraction techniques have successfully determined crystalline structures. Nevertheless, new techniques are necessary as conventional methods cannot provide detailed structural information to probe the disordered structures, such as nanostructured and amorphous materials.<br/><br/>The pair distribution function (PDF) method based on X-ray and neutron diffraction is widely employed for providing quantitative information in amorphous materials ¹. Nonetheless, understanding medium-range structural order in amorphous materials is non-trivial, where the position of atoms cannot be assigned by any equation based on translation vectors. Electron Diffraction (ED) related PDF (ePDF) in Transmission Electron Microscope has the advantage of investigating ordering locally. However, ePDF-based analyses may be affected by dynamical effects, altering the scattering intensities.<br/><br/>This work aims to expand the developed methodology to battery materials, by employing electron diffraction data to obtain PDF coupled with electron energy loss spectroscopy ². This will enable us to investigate the role of volume expansion during lithiation in silicon-carbon-based anode materials which is crucial for the functioning of the electrode.<br/><br/><b>References:</b><br/>1. Zeng, L., Tran, D. T., Tai, C.-W., Svensson, G. & Olsson, E. Atomic structure and oxygen deficiency of the ultrathin aluminium oxide barrier in Al/AlOx/Al Josephson junctions. <i>Sci Rep</i> <b>6</b>, 29679 (2016).<br/>2. Tran, D. T., Svensson, G. & Tai, C.-W. SUePDF: a program to obtain quantitative pair distribution functions from electron diffraction data. <i>J Appl Cryst</i> <b>50</b>, 304–312 (2017).