Abstract
Droplet-based patterning techniques have demonstrated great effectiveness in fabricating highly ordered arrays for applications of functional materials in photonics, optoelectronics, and sensing technologies. Droplets act as small units and microreactors, providing controlled physical or chemical interactions, thereby enabling solution-processable material deposition on various substrates in a high-throughput, large-scale manner. Particularly for perovskite materials, droplet techniques allow the bottom-up fabrication of perovskite arrays, fully exploiting the cost reduction and efficiency improvement of solution-based processing for perovskite devices. This article aims to review the principles and recent progress in microdroplet array technology, explore its potential in perovskite material patterning, and discuss the broad applications of perovskite arrays in photonic and optoelectronic fields, including light-emitting diodes, photodetectors, fluorescent anticounterfeiting, and color conversion layers, to provide a comprehensive engineering reference for readers.