Seungmin Lee1,Yeoun-Woo Jang2,Kyung Mun Yeom1,Kiwan Jeong2,Kwang Choi1,Mansoo Choi2,Jun Hong Noh1
Korea University1,Seoul National University2
Seungmin Lee1,Yeoun-Woo Jang2,Kyung Mun Yeom1,Kiwan Jeong2,Kwang Choi1,Mansoo Choi2,Jun Hong Noh1
Korea University1,Seoul National University2
Ruddlesden-Popper two-dimensional (2D) perovskite in the junction between the three-dimensional (3D) perovskite and hole transporting layer of a device provided not only the effective improvement for performance through the defect passivation on the top of the surface, but also endowed the stability for the device. However, a solution process, general approaches forming 2D (C<sub>4</sub>H<sub>9</sub>NH<sub>3</sub>)<sub>2</sub>PbI<sub>4</sub> perovskite on the surface, must accompany a quasi-2D perovskite because it was based on the surface reaction. The intact 2D/3D perovskite bilayer architecture, formed by the “Solid-state Inplane-Growth (SIG)” method, can permit enhancement of performance and stability through the growth of a stable and highly crystalline 2D perovskite on the 3D surface. Also, it was observed that the thickness of intact 2D perovskite depended on an open-circuit voltage and that the built-in potential was formed at the 2D layer in the 2D/3D junction. Thereby, the 2D/3D p-p isotype heterojunction with the thicker 2D layer maximizing the potential furnished the device with a certified 24.35% of quasi-steady-state efficiency with 1.185 V of the open-circuit voltage in 1.55 eV bandgap. The device with intact 2D/3D showed stabilities of 94% of initial efficiency for a damp heat test (85°C/85% relative humidity) after 1,056 h, as well as 98% after 1,620 h under 1-sun illumination.