Observation of mechanical fracture and corresponding domain structure changes of polycrystalline PbTiO3 nanotubes

PbTiO3 (PTO) nanotubes (NTs) were synthesized at various temperatures by gas phase reaction between PbO gas and anatase TiO2 NTs and characterized by piezoresponse force microscopy (PFM). PTO ferroelectric phase was synthesized at as low as 400 °C as evidenced by PFM domain images and piezoresponse hysteresis loop measurement. Furthermore, the PTO NTs fabricated at above 500 °C underwent mechanical fracture through development of nanocracks due to grain growth, leading to ferroelectric domains with larger size and lower aspect ratio. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)