Electrostatic Force–Driven Oxide Heteroepitaxy for Interface Control

Oxide heterostructure interfaces create a platform to induce intriguing electric and magnetic functionalities for possible future devices. A general approach to control growth and interface structure of oxide heterostructures will offer a great opportunity for understanding and manipulating the functionalities. Here, it is reported that an electrostatic force, originating from a polar ferroelectric surface, can be used to drive oxide heteroepitaxy, giving rise to an atomically sharp and coherent interface by using a low‐temperature solution method. These heterostructures adopt a fascinating selective growth, and show a saturation thickness and the reconstructed interface with concentrated charges accumulation. The ferroelectric polarization screening, developing from a solid–liquid interface to the heterostructure interface, is decisive for the specific growth. At the interface, a charge transfer and accumulation take place for electrical compensation. The facile approach presented here can be extremely useful for controlling oxide heteroepitaxy and producing intriguing interface functionality via electrostatic engineering. TiO2/PbTiO3, SrTiO3/PbTiO3, and BiFeO3/PbTiO3 heterostructures with atomically sharp interfaces are synthesized by a low‐temperature hydrothermal method (100–200 °C). This heteroepitaxial growth is driven by a strong electrostatic force originating from the polar surfaces of PbTiO3 single‐domain nanoplates. Ferroelectric polarization screening leads to the selective growth and saturation thickness, accompanied with a charge transfer and accumulation near the interface.