One-step synthesis of epitaxial 3D/2D metal halide perovskite heterostructures

Facile and scalable synthesis of perovskite heterostructures with well-controlled heterointerfaces remains challenging. Herein, we developed a simple one-step solution method to prepare 3D/2D CsPbBr3/PEA(2)PbBr(4) perovskite heterostructures with a well-defined epitaxial structure in the gram scale. The formation mechanism was detailed by using in situ time-resolved photoluminescence (PL) spectroscopy analysis. In addition, a series of 3D/2D epitaxial heterostructures were also prepared by changing the organic cations or halogen anions. Due to the effective charge separation and transfer, photodetectors based on the type-II 3D/2D CsPbBr3/PEA(2)PbBr(4) heterostructures showed up to 120 times higher photoresponsivities and 50 times higher on/off ratios compared to devices based on single component perovskites.

Automated summary

A facile and scalable method for preparing well-controlled perovskite heterostructures is developed in this study. The 3D/2D CsPbBr3/PEA(2)PbBr(4) perovskite heterostructures with epitaxial structure are successfully synthesized via a one-step solution method. The formation mechanism is studied using in-situ time-resolved photoluminescence spectroscopy. Photodetectors based on these heterostructures exhibit significantly improved photoresponsivities and on/off ratios compared to single component perovskite devices.