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Solution processability is a prominent advantage for the commercial fabrication of perovskite solar cells (PSCs). However, ionic side reactions can cause perovskite solutions to age, which greatly limits the industrial prospects for reproducible production of PSCs. Herein, the mechanism of underlying halogen anion side reactions is elucidated and an effective scheme for managing halogen anions is proposed. The oxidation of halogen anions is the main factor of solution aging. The addition of iodine monobromide (IBr) stabilizes the precursor solution by promoting the reverse oxidation reaction. Meanwhile, IBr can manage the loss of halogen anion in perovskite layers, effectively reducing the defect density. Moreover, IBr can improve the crystallization process to prepare perovskite films with large‐sized grains and high crystallinity. As a result, the IBr‐based perovskite solution can be stored for 14 days, the optimal device efficiency (24.05% at 0.09 cm2) and long‐term operational stability are far superior to control samples. By this strategy, a large‐area perovskite solar module with an efficiency of 19.34% is fabricated on the 6 × 6 cm2 substrate. This study is dedicated to providing a strategy for managing halogen anions to inhibit solution aging and improve film quality. [ABSTRACT FROM AUTHOR]

1D metal halide perovskite (MHP) nanowires (NWs) have energized research interest owing to their unique characteristics; they are grain‐boundary‐free, efficiently transport axial carriers, in conjunction with strong radial spatial confinement. Herein, recent progress in the synthesis, integration, property characterization, and advanced optoelectronic applications of MHP NWs is systematically reviewed. The approaches to synthesize MHP NWs are mainly classified into solution‐phase and vapor‐phase methods, as well as the top‐down technique. Meanwhile, highly ordered patterns/templates‐assisted and surface‐guided alignment methods are utilized to integrate MHP NWs into NW arrays. The enhanced long‐term stability and superior optoelectronic properties of MHP NWs enable excellent optoelectronic device performance, where solar cells, photodetectors, image sensors, bionic eyes, light‐emitting diodes, resistive random‐access memories, and field‐effect transistors are mainly discussed. Finally, some perspectives for further direction of exploration to improve the device performance and path ways toward their practical applications are also provided. [ABSTRACT FROM AUTHOR]

Background: Genetic testing of UGT1A1 was used to facilitate the diagnosis of Gilbert syndrome, and analyze the distribution features of pathogenic variants in the Chinese population. Methods: DNA was extracted from whole blood samples of patients with unconjugated hyperbilirubinemia, and sequencing of the UGT1A1 gene was performed after PCR amplification. After alignment with reference sequences, the known pathogenic variants were identified, the variant spectrum was analyzed, and the pathogenicity of novel variants was predicted using online mutation prediction tools. Results: A total of 117 patients were confirmed with Gilbert syndrome by UGT1A1 genetic diagnosis, where the most common pathogenic variants included promoter A(TA)7TAA insertion and p.Gly71Arg missense variant. Following novel variants were also identified: p.Ala61Gly, p.Tyr67Phe, p.Leu166Alafs*16, p.Arg240Lys, p.Ser306Phe, p.Arg341Gln, and p.Glu424* variants. Conclusions: Genetic testing of UGT1A1 in clinical practices could facilitate confirming Gilbert syndrome and performing differential diagnosis. The pathogenic variant spectrum in the Chinese population was similar to other Asian populations. The novel pathogenic variants identified in this study require further investigation. [ABSTRACT FROM AUTHOR]

Ligand‐solvent engineering has been widely applied to improve the quality of perovskite films by forming intermediate films. However, there is an inconsistent understanding in the studies on the composition and mechanism of intermediate films formed by different ligand solvents, and the influence on perovskite film morphology is still elusive. Herein, the pure intermediate films (composed of pure crystal nucleus and amorphous precursor) are fabricated by the addition of ligand solvents with different coordination abilities. Notably, a single heterogeneous nucleation process is induced by the pure intermediate film, resulting in the formation of vertically arranged internal perovskite crystals with few horizontal boundaries, that improve charge transfer and device performance. Furthermore, the small and uniform crystals obtained by adding a ligand solvent with weak coordination ability result in smooth films and a smaller device current (Jsc = 22.74 mA cm−2, PCE = 19.58%). In contrast, the large and uneven crystals obtained by strong coordination ability lead to rough films and a larger device current (Jsc = 23.24 mA cm−2, PCE = 20.72%). This study is devoted to providing a significance reference for the fabrication of perovskite films with vertically arranged internal grains and superior surface textures. [ABSTRACT FROM AUTHOR]

The nucleation and crystallization processes within solution‐processed deposition is key for obtaining perovskite films with high quality. Herein, the synergistic effect of Cs+, ligand solvent (tetramethylene sulfoxide, TMSO), and methylammonium ions (MA+) on nucleation and crystallization procedures of preparing perovskites films is studied. The results reveal that producing α‐phase nuclei in the intermediate‐phase film (a perovskite film formed by removing the solvent before annealing) is the key factor for obtaining α‐phase‐pure perovskites, wherein Cs+ is necessary for reducing the formation energy of the α‐phase. In addition, the nonvolatile ligand (TMSO) is used to inhibit rapid nucleation, because it can form a stable intermediate phase. Furthermore, the introduction of the volatile MA+ cations compound (MACl) combined with Cs+ contributed to the direct formation of α‐phase nuclei in the intermediate‐phase film, and ion exchange (between FA+ and MA+) occurs during the subsequent annealing process, which leads to the formation of large‐grain perovskite film with good crystallinity. Maximum power conversion efficiencies of 22.08% and 16.88% are obtained via this strategy for a perovskite solar cell on a small area (active area: 0.09 cm2) and a perovskite solar module (aperture area: 12.92 cm2), respectively. [ABSTRACT FROM AUTHOR]

The fabrication of large area perovskite solar modules (PSMs) is attracting increasing attention. Traditionally, thin film solar modules are prepared by laser‐engraving several isolated lines to create a series of subcells. This process inevitably leads to an increase in series resistance when combining the subcells. Herein, a facile structure combining series and parallel cell connections is designed and developed for constructing PSMs. A champion power conversion efficiency (PCE) of 18.82% is achieved for perovskite composite modules with a designated area of 21.06 cm2. Furthermore, the PSMs can continue to operate even when parts of the device are shaded or broken. Because of the repeated structural arrangement, these modules may be suitable for fabrication on a broader scale for commercial applications. [ABSTRACT FROM AUTHOR]

Multilayered photovoltaic absorbers have triggered widespread attention for their unique structure and properties. However, multilayered materials in the randomly oriented polycrystalline thin‐film lead to ineffective carrier transport and collection, which hinders the process of achieving high‐performance solar cells. Herein, this issue is tackled by producing the three‐dimensional (3D) heterojunction BiI3 nanosheets (NSs) solar cells, which embed vertically aligned monocrystalline BiI3 NSs into spiro‐OMeTAD. The preferred orientation of BiI3 NSs and large p‐n junction areas of 3D heterojunction structure enable a strong light absorption and effective carrier transport and collection, and thus a power conversion efficiency (PCE) of 1.45% was achieved. Moreover, this PCE is the highest ever reported for BiI3 based solar cells to our best knowledge. Moreover, the nonencapsulated device remained 96% of the initial PCE after 24 h continuous one sun illumination at ~70% humidity condition, and 82% of the initial PCE after 1‐month storage at ~30% humidity condition. [ABSTRACT FROM AUTHOR]

The base-pair sequences are the foundation for the biological processes of DNA or RNA, and base-pair mismatch is very important to reveal genetic diseases and DNA rearrangements. However, the lack of well-defined structural information about base-pair mismatch is obstructing the investigation of this issue. The challenge is to crystallize the materials containing the base-pair mismatch. Engineering the small-molecule mimics or model is an effective strategy to solve this issue. Here, six cytidine-5′-monophosphate (CMP) and 2′-deoxycytidine-5′-monophosphate (dCMP) coordination polymers were reported containing cytosine-cytosine base-pair mismatch (i-motif), and their single-crystal structures and chiralities were studied. The precise control over the formation of the i-motif was demonstrated, in which the regulating of supramolecular interactions was achieved based on molecular design. In addition, the chiralities of these coordination polymers were investigated according to their crystal structures and solution- and solid-state circular dichroism spectroscopy. [ABSTRACT FROM AUTHOR]

A colorimetric and fluorescent sensor for trace water in methanol has been designed and characterized, which is a kind of aluminium-Schiff base coordination complex derived from diaminomaleonitrile. The fluorescence properties of this complex have been studied based on excited state intramolecular proton transfer (ESIPT) and intramolecular charge transfer (ICT) mechanism. The fluorescent emission of Al-L complex can be quenched by 0.1% water and distinguished by naked eyes. The detection limitation is 0.01% recognized by fluorescence spectra. [ABSTRACT FROM AUTHOR]

The incorporation of various cations and halides to form mixed perovskites has enabled perovskite solar cells (PSCs) to exceed 20% power conversion efficiencies (PCEs). However, they are primarily prepared by solution methods, which limit film uniformity and scalability. Although co‐evaporation is used to prepare all‐vacuum‐deposited PSCs with a decent performance, it involves multiple sources and quartz crystal monitors (QCMs) to simultaneously control deposition rates and film thicknesses, which increase production cost and fabrication complexity and interfere QCMs' reading precision. Herein, a simple and cost‐effective sequential vapor deposition involving only one QCM and two sources is demonstrated as an advantageous and reliable method to fabricate high‐quality and uniform mixed‐cation mixed‐halide perovskite films with microscale grain sizes and extraordinary morphology for the PSC application. In addition, for the first time, radio frequency (RF)‐sputtered SnO2 is implemented into all‐vacuum‐deposited PSCs as an electron transport layer (ETL). Together with evaporated copper phthalocyanine (CuPc) as a thermally and chemically stable low‐cost hole transport layer (HTL), alternative to the commonly used 2,2′,7,7′‐tetrakis(N,N‐di‐p‐methoxyphenylamino)‐9,9′‐spirobifluorene (Spiro‐OMeTAD), which is costly, highly hygroscopic, and deliquescent, a respectable PCE of 15.14% is achieved with a promising device stability and negligible hysteresis. [ABSTRACT FROM AUTHOR]

A single device with a variety of capabilities is highly attractive for the increasing demands of complex and multifunctional optoelectronics. A hybrid heterojunction formed between CsPbBr3 halide perovskite and chalcogenide quantum dots is demonstrated. The heterojunction served as an asymmetric active layer allows not only charge separation/exciton dissociation in a benign process, but also carrier injection/recombination with the suppression of bulk and interfacial nonradiative recombination. An individual device incorporating such a heterojunction is therefore implemented with an integration of proof‐of‐concept functions, including a voltage controllable multicolor light‐emitting diode, an exceptionally high photovoltage energy‐harvesting device, and an ultrafast photosensitive detector. The figures of merit of the light‐emitting diode remarkably surpass those of the corresponding single‐active‐layer device, particularly in terms of its bright electroluminescence and superior long‐term stability. The asymmetric active layer concept provides a feasible route to design efficient multifunctional and monofunctional devices in the future. [ABSTRACT FROM AUTHOR]