Twinning-mediated anomalous alignment of rutile films revealed by synchrotron X-ray nanodiffraction

Abstract

Summary Nanotwin structures in materials engender fascinating exotic properties. However, twinning usually alter the crystal orientation, resulting in random orientation and limited performances. Here, we report a well-aligned rutile TiO 2 nanotwin film with superior preferential orientation than its isostructural substrate. By means of the synchrotron X-ray Laue nanodiffraction technique, the crystal orientation, twin boundaries, and deviatoric stresses of the film were quantitatively imaged at unprecedented spatial resolution to unravel the underlying mechanism of this anomalous alignment. Massive {101}-type rutile nanotwins were observed, and a crystallographic relationship of the heteroepitaxy was proposed. The rapid twinning and twin-controlled heteroepitaxy are responsible for the texture improvement. This work would open up opportunities for rational design of better twin-based functional materials, and implies the powerful capabilities of X-ray nanodiffraction technique for multidisciplinary applications.

V-Shaped RuO2 Nanotwin Complex Defect Facilitation of OER Reaction

“…Furthermore, the sodium-decorated amorphous/crystalline RuO 2 (a/c-RuO 2 ) interface containing rich oxygen vacancies (V O s) was developed as an excellent pH-universal OER electrocatalyst, showing remarkable resistance to acid corrosion and oxidation during the OER . The short-range disordered structure at the interface introduces abundant unsaturated bonds and V O s. In fact, high-resolution transmission electron microscopy images revealed that a large number of twin structures and point defects can be observed in the distortion region, showing obvious local disorder characteristics. , Thus, due to the characteristics of short-range disorder and long-range order, local amorphous structures could be simulated by introducing nanotwins with point defects, which constructed the characteristic structure combining local lattice distortion and unsaturated bonds. The nanotwins could not be ignored when investigating the OER reaction mechanism .…”