Probing the growth habit of highly single crystalline twinned V-shape RuO₂ nanowires by polarized raman scattering

Polarized Raman scattering measurements have been carefully employed to explore the growth orientation and direction of a highly single crystalline twinned V-shaped ruthenium dioxide nanowire which were directly grown on a Si wafer with the thin SiO₂ layer at 750°C without any catalyst via a vapor phase transport process. Interestingly, the morphology of most of nanowires represents a well-defined twinned V-shape with a specific angle of approximately 52° between the two branches under a specific growth condition. We measured polarized Raman spectra of a single V-shaped nanowire and calculated the Raman intensity of RuO₂ nanowire by considering a crystal coordinate. We observed that each branch of a V-shaped RuO₂ nanowire grows into [001] direction, exactly consistent with the prediction of the growth direction by high resolution transmission electron microscopy (HRTEM).