Large‐area organic–inorganic hybrid perovskite (OIHP) single crystals have attracted intensive interest for diverse device applications. However, conventional growth methods usually suffer from limited and disordered mass transport in the crystal growth process, making the large‐area fabrication of OIHP single crystals with controllable thickness remain a formidable challenge. Here, for the first time, a three‐dimensional confined crystallization (3DCC) strategy is reported to achieve centimeter‐scale growth of a OIHP single‐crystal array with tunable thickness. The 3D geometrical channels can not only induce an oriented capillary flow to enhance the mass transport by up to 100 folds, but also can effectively confine the crystal crystallization in both in‐plane and out‐of‐plane directions, thereby remarkably improving the crystallinity and thickness control of the crystals. Furthermore, a self‐driven lateral‐structured photodetector is demonstrated based on the resultant OIHP single‐crystal array with significant long‐term stability (>36 days, maintaining 80% of the initial performance) and outstanding device performance (linear dynamic range of 73 dB). The ability of the 3DCC strategy to scale up the growth of high‐quality perovskite single crystals opens a pathway for large‐scale and integrated optoelectronic applications.

Narrow-bandgap Sn-Pb mixed perovskite single crystals are highly promising as photoactive materials for efficient and low-cost near-infrared (NIR) photodetectors. However, because of the significant difference of the crystallization velocity for...

Organic photodetectors, as an emerging wearable photoplethysmographic (PPG) technology, offer exciting opportunities for next‐generation photonic healthcare electronics. However, the mutual restraints among photoresponse, structure complexity, and fabrication cost have intrinsically limited the development of organic photodetectors for ubiquitous health monitoring in daily activities. Here, an effective route to dramatically boost the performance of organic photodetectors with a solution‐processed integration circuit for health monitoring application is reported. Through creating an ideal metal–semiconductor junction interface that minimizes the trap states within the device, solution‐printed organic field‐effect transistors (OFETs) are achieved with an ultrahigh signal amplification efficiency of 37.1 S A−1, approaching the theoretical thermionic limit. Consequently, monolithic integration of the OFET with an organic photoconductor enables the remarkable amplification of photoresponse signal‐to‐noise ratio by more than four orders of magnitude from 5.5 to 4.6 × 105, which is able to meet the demand for accurately extracting physiological information from the PPG waveforms. This work offers an effective and versatile approach to greatly enhance the photodetector performance, promising to revolutionize health monitoring technologies.

Narrow-band-gap Sn−Pb perovskites have emerged as one of the most promising solution-processed near-infrared (NIR) light-detection technologies, with the key figure-of-merit parameters already rivaling those of commercial inorganic devices, but maximizing the cost advantage of solution-processed optoelectronic devices depends on the ability to fast-speed production. However, weak surface wettability to perovskite inks and evaporation-induced dewetting dynamics have limited the solution printing of uniform and compact perovskite films at a high speed. Here, we report a universal and effective methodology for fast printing of high-quality Sn−Pb mixed perovskite films at an unprecedented speed of 90 m h −1 by altering the wetting and dewetting dynamics of perovskite inks with the underlying substrate. A line-structured SU-8 pattern surface to trigger spontaneous ink spreading and fight ink shrinkage is designed to achieve complete wetting with a near-zero contact angle and a uniform draggedout liquid film. The high-speed printed Sn−Pb perovskite films have both large perovskite grains (>100 μm) and excellent optoelectronic properties, yielding highly efficient self-driven NIR photodetectors with a large voltage responsivity over 4 orders of magnitude. Finally, the potential application of the self-driven NIR photodetector in health monitoring is demonstrated. The fast printing methodology provides a new possibility to extend the manufacturing of perovskite optoelectronic devices to industrial production lines.