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Energy loss in perovskite grain boundaries (GBs) is a primary limitation toward high‐efficiency perovskite solar cells (PSCs). Two critical strategies to address this issue are high‐quality crystallization and passivation of GBs. However, the established methods are generally carried out discretely due to the complicated mechanisms of grain growth and defect formation. In this study, a combined method is proposed by introducing 3,4,5‐Trifluoroaniline iodide (TFAI) into the perovskite precursor. The TFAI triggers the union of nano‐sized colloids into microclusters and facilitates the complete phase transition of α‐FAPbI3 at room temperature. The controlled chemical reactivity and strong steric hindrance effect enable the fixed location of TFAI and suppress defects at GBs. This combination of well‐crystallized perovskite grains and effectively passivated GBs leads to an improvement in the open circuit voltage (Voc) of PSCs from 1.08 V to 1.17 V, which is one of the highest recorded Voc without interface modification. The TFAI‐incorporated device achieved a champion PCE of 24.81%. The device maintained a steady power output near its maximum power output point, showing almost no decay over 280 h testing without pre‐processing. [ABSTRACT FROM AUTHOR]

Realization of remote wearable health monitoring (RWHM) technology for the flexible photodiodes is highly desirable in remote‐sensing healthcare systems used in space stations, oceans, and forecasting warning, which demands high external quantum efficiency (EQE) and detectivity in NIR region. Traditional inorganic photodetectors (PDs) are mechanically rigid and expensive while the widely reported solution‐processed mixed tin‐lead (MSP) perovskite photodetectors (PPDs) exhibit a trade‐off between EQE and detectivity in the NIR region. Herein, a novel functional passivating antioxidant (FPA) strategy has been introduced for the first time to simultaneously improve crystallization, restrain Sn2+ oxidization, and reduce defects in MSP perovskite films by multiple interactions between thiophene‐2‐carbohydrazide (TAH) molecules and cations/anions in MSP perovskite. The resultant solution‐processed rigid mixed Sn–Pb PPD simultaneously achieves high EQE (75.4% at 840 nm), detectivity (1.8 × 1012 Jones at 840 nm), ultrafast response time (trise/tfall = 94 ns/97 ns), and improved stability. This work also highlights the demonstration of the first flexible photodiode using MSP perovskite and FPA strategy with remarkably high EQE (75% at 840 nm), and operational stability. Most importantly, the RWHM is implemented for the first time in the PIN MSP perovskite photodiodes to remotely monitor the heart rate of humans at rest and after‐run conditions. [ABSTRACT FROM AUTHOR]

A porous metal–organic framework [Ba(H2LLOMe 2−)·DMF·H2O]·2DMF (UPC‐2) (H4LLOMe = 4ʹ,4ʹʹʹ‐(2,3,6,7‐tetramethoxyanthracene‐9,10‐diyl)bis([1,1ʹ‐biphenyl]‐3,5‐dicarbo‐xylic acid N,N‐Dimethylformamide [DMF]), which can act as an excellent chemiluminescence microreactor, is designed and constructed. In the framework of UPC‐2, the catalytic Ba cluster and electron‐rich anthracene fluorescent centers are fixed and interconnected in an orderly fashion, and this can shorten the energy transfer path and weaken the relaxation of the chemiluminescence process. Meanwhile, the rhombic channels of UPC‐2 can provide a proper diffusion ratio of reactants to support a stable and continuous energy supply. The UPC‐2 chemiluminescence microreactor exhibits an ultrastrong and long‐lasting light emission, which possesses potential application in emergency lights and biological mapping. The concept of the chemiluminescence microreactor and its construction using a metal–organic framework as a platform will promote further research in the design and fabrication of functional MOFs for chemiluminescence applications. [ABSTRACT FROM AUTHOR]