Two conjugated covalent organic frameworks (COFs) are successfully synthesized and are introduced as the interface modifier in perovskite solar cells (PVSCs) to enhance the overall performance.

As the new‐generation photovoltaic technologies, organic solar cells (OSCs) and perovskite solar cells (PVSCs) offer significant advantages over Si‐ and CdTe‐based solar cells, that is, facile low‐temperature solution processability and excellent cost‐performance ratios. At present, OSCs and PVSCs have achieved very high certified power conversion efficiencies of 17.5% and 25.5%, respectively, which have already approached the efficiencies needed for commercial applications. However, there are still several obstacles that need to be overcome before they can be deployed as new‐generation of printable photovoltaic technologies. More efforts also need to be devoted to finding applicable methods for manufacturing highly efficient, large‐area devices and improving their long‐term operational stability. Thus, this article provides a comprehensive review on the current status and technical challenges for commercializing these two solution‐processable solar cells.

Two‐dimensional (2D) tin (Sn)‐based perovskites have recently received increasing research attention for perovskite transistor application. Although some progress is made, Sn‐based perovskites have long suffered from easy oxidation from Sn2+ to Sn4+, leading to undesirable p‐doping and instability. In this study, it is demonstrated that surface passivation by phenethylammonium iodide (PEAI) and 4‐fluorophenethylammonium iodide (FPEAI) effectively passivates surface defects in 2D phenethylammonium tin iodide (PEA2SnI4) films, increases the grain size by surface recrystallization, and p‐dopes the PEA2SnI4 film to form a better energy‐level alignment with the electrodes and promote charge transport properties. As a result, the passivated devices exhibit better ambient and gate bias stability, improved photo‐response, and higher mobility, for example, 2.96 cm2 V−1 s−1 for the FPEAI‐passivated films—four times higher than the control film (0.76 cm2 V−1 s−1). In addition, these perovskite transistors display non‐volatile photomemory characteristics and are used as perovskite‐transistor‐based memories. Although the reduction of surface defects in perovskite films results in reduced charge retention time due to lower trap density, these passivated devices with better photoresponse and air stability show promise for future photomemory applications.

As the power conversion efficiency (PCE) of organic photovoltaics (OPVs) approaches 19%, increasing research attention is being paid to enhancing the device's long‐term stability. In this study, a robust interface engineering of graphene oxide nanosheets (GNS) is expounded on improving the thermal and photostability of non‐fullerene bulk‐heterojunction (NFA BHJ) OPVs to a practical level. Three distinct GNSs (GNS, N‐doped GNS (N‐GNS), and N,S‐doped GNS (NS‐GNS)) synthesized through a pyrolysis method are applied as the ZnO modifier in inverted OPVs. The results reveal that the GNS modification introduces passivation and dipole effects to enable better energy‐level alignment and to facilitate charge transfer across the ZnO/BHJ interface. Besides, it optimizes the BHJ morphology of the photoactive layer, and the N,S doping of GNS further enhances the interaction with the photoactive components to enable a more idea BHJ morphology. Consequently, the NS‐GNS device delivers enhanced performance from 14.5% (control device) to 16.5%. Moreover, the thermally/chemically stable GNS is shown to stabilize the morphology of the ZnO electron transport layer (ETL) and to endow the BHJ morphology of the photoactive layer grown atop with a more stable thermodynamic property. This largely reduces the microstructure changes and the associated charge recombination in the BHJ layer under constant thermal/light stresses. Finally, the NS‐GNS device is demonstrated to exhibit an impressive T80 lifetime (time at which PCE of the device decays to 80% of the initial PCE) of 2712 h under a constant thermal condition at 65 °C in a glovebox and an outstanding photostability with a T80 lifetime of 2000 h under constant AM1.5G 1‐sun illumination in an N2‐controlled environment.

Developing new chemistry to passivate the defects in the perovskite layer is highly desired in researching high-performance and stable perovskite solar cells (PVSCs). We herein explore supramolecular chemistry to passivate...