Accelerated room temperature synthesis of desired cesium lead halide perovskite nanocrystals via automated microfluidic meta learner

•AMML facilitates facile synthesis of perovskite nanocrystals.•AMML accurately locates target CsPb(BrxI1-x)3 nanocrystals and screens effectively.•The perovskite nanocrystal-based white LED achieves 121% NTSC color gamut. Cesium lead halide perovskite nanocrystals (CLHP NCs) have demonstrated their unique optical properties in next-generation lighting and display devices through controlling the size, shape, and composition. However, achieving their target-specific synthesis with numerous reaction parameters via traditional methods requires long and tedious optimization. Herein, a fully automated microfluidic meta learner (AMML) coupled with coiled flow inverter reactors (CFIR) is developed for facilely synthesizing desired CLHP NCs. CFIR offers a strong support in reagent mixing for AMML, producing high-quality NCs with negligible by-products. By concatenating the model-agnostic meta-learning and feedback control, AMML provides quick and accurate locating of target emission CsPb(BrxI1-x)3 NCs in the wide range from 519 nm to 636 nm based on 3 data points, even in the no-prior-knowledge part. AMML exhibits excellent screening ability (25 experiments in 110 min) of reaction parameters for controllable synthesis of CsPbBr3 NCs. Based on the optimal results, a white light-emitting diode is fabricated with excellent stability and a wide color gamut of 121 % NTSC. AMML offers a novel paradigm for the large-scale synthesis of desired NCs and can be applied to other NCs for intelligent and sustainable discovery.