Polymer-Assisted Controllable Growth of Large-Scale and High-Quality Two-Dimensional Perovskite Single-Crystal...

Two-dimensional (2D) hybrid perovskites have come into the spotlight for optoelectronic applications due to their numerous exceptional properties. However, the lack of efficient methods for controllable growth of large-scale and high-quality 2D perovskite single-crystal (PSC) arrays restricts their practical application in integrated optoelectronic devices, such as photoconductor-type photodetector integration. Herein, a polyvinylpyrrolidone (PVP)-assisted template-space-confined method is proposed for growing patterned 2D PSC microplate arrays, in virtue of which a series of 2D PSC microplates in various Ruddlesden-Popper (RP) and Dion-Jacobson (DJ) phases, as well as tunable lateral size and thickness, can be achieved. It is revealed that coordination-bonding interactions between the carbonyl groups of PVP molecules and perovskite precursor ions contribute to the uniform and continuous growth of 2D PSC microplate arrays spanning 100 mm² areas. Specifically, the (PEA)₂PbI₄ PSC microplate arrays synthesized with the optimal 4 wt % PVP concentration exhibit high-quality crystallinity and low defect/trap density. In consequence, the photodetector array based on as-grown (PEA)₂PbI₄ microplate arrays is demonstrated with excellent photodetection performance and low device-to-device variation. This method enables controlling and scaling up the growth of high-quality 2D PSC microplate arrays, which constitutes an important step toward large-scale and integrated optoelectronic systems.