Structural changes induced by Sn, Zr, Al substitution in Zn_kIn₂O_k+3 transparent conducting oxides powders as deduced by transmission electron microscopy

Sn, Zr and Al substituted Zn_kIn₂O_k+3 powders were made using high temperature solid state reactions. The resulting samples were first characterized by means of powder X-ray diffraction (XRD) and then by transmission electron microscopy (TEM) to identify the microstructures and phase compositions occasionally occurring within a particle. We found that the substituted powder samples are usually composed of particles made of Zn_kIn₂O_k+3 polytypes intergrowth mixed with grains of In₂O₃-type structure, rather than being single phase. From a complete analysis of the collected HRTEM images we obtained a statistical polytype population distribution that was used to satisfactorily simulate the experimental XRD patterns based on Hendricks and Teller approximation.