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Perovskite materials have demonstrated significant potential in X‐ray detection due to their high atomic number and robust X‐ray absorption capacity, especially organic–inorganic hybrid perovskites. Among these, CH(NH2)2PbI3 (FAPbI3) stands out for its narrow bandgap and robust absorption properties. However, FAPbI3 undergoes a rapid phase transition from a black octahedral perovskite phase to a yellow non‐perovskite phase under environmental conditions. This work addresses this issue by proposing the doping of Bi elements with mixed valence at the Pb site, verified through density functional theory simulations. The results indicate that Bi doping increases the formation of FA ionic vacancies, enhancing degradation energy and stabilizing the perovskite phase. FAPb0.99Bi0.01I3 exhibits higher ion‐migration activation energy (0.75 eV), carrier mobility (6.88 × 10−3 cm2 V−1), and carrier lifetime compared to FAPbI3. Additionally, Bi doping reduces FAPbI3 perovskite crystal defects, inhibits ion migration, and increases resistivity. These improvements confirm the feasibility of B‐site non‐homovalent doping in perovskite X‐Ray detector applications. [ABSTRACT FROM AUTHOR]

Quasi−2D perovskite films with multiple quantum well structures can provide a large Stokes shift and efficient photoluminescence (PL), which have great potential in the application of luminescent solar concentrators (LSCs). However, its low photoelectric conversion efficiency and poor stability remain obstacles to commercial application. Here, a multifunctional molecule additive octyltriphenylphosphonium bromide is introduced to prepare high‐quality perovskite LSCs. The multifunctional molecule can simultaneously passivate perovskite cations and anions, reducing the defect sites and improving the photoluminescence quantum yield (PLQY) of the perovskite nanocrystals. Triphenylphosphine groups with high steric hindrance effect can hinder ion migration; the hydrophobic properties of the long alkyl chain prevent water erosion, which together improves the stability of the perovskite films. The multifunctional molecule passivated perovskite film has a high PLQY of 100% and retains 96% of the initial PL intensity after 30 days of indoor storage. The perovskite LSC device achieves a maximum optical efficiency of 6.5% at a geometric factor of 3.1. The findings open a new way to boost the performance of perovskite‐based LSCs. [ABSTRACT FROM AUTHOR]

Power conversion efficiencies (PCEs) of the methylammonium‐free (MA‐free) perovskite solar cells (PSCs) are constantly lagging behind those of the most extensively researched triple cation mixed PSCs due to their subpar perovskite films. Here, two guanidine‐based passivation agents are proposed, that are, sulfaguanidine (S‐Gua) and 1‐acetylguanidine (A‐Gua) that can be applied to optimize the film quality of MA‐free perovskite for minimizing the efficiency discrepancy between the two types of PSCs. Through strong coordination with Pb2+ and hydrogen bonding with formamidinium (FA+), the two passivation additives can reduce bulk defects and suppress non‐radiative recombination, which in turn enhance the charge extraction and transfer efficiency. Consequently, the S‐Gua‐ and A‐Gua‐treated devices achieve PCEs of 24.34% and 23.77%, respectively. Both PCEs are greater than that of the control device (23.03%), and the 24.34% PCE is comparable with that of the best MA‐free inverted PSCs with narrower bandgaps. Moreover, the S‐Gua‐treated devices maintain 89.3% and 82.0% of their initial PCEs after aging for 800 h and heating (85 °C) for 340 h in ambient air without any encapsulation, respectively. This work offers comprehensive insights into the use of guanidine‐based additives to achieve high‐quality perovskite films and subsequently state‐of‐the‐art MA‐free PSCs. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid perovskite solar cells (HPSCs) are gaining attention as a promising technology for next‐generation photovoltaic devices owing to their impressive power conversion efficiency (PCE) and cost‐effective fabrication methods. Although, solution‐processed passivation using 2D perovskites can improve the interface recombination, this approach hampers its effective charge transportation. In this study, the study investigates the properties and performance of the bilayer 3D/3D methylammonium lead iodide (MAPbI3)/formamidinium lead iodide (FAPbI3)‐based perovskite heterojunction (BPHJ) to address these concerns. The bilayer structure consists of two distinct perovskite absorbers having independent structure that are sandwiched between two charge transporting layer (CTLs) to make functional device. First, the fabrication process is optimized to achieve high‐quality MAPbI3 perovskite films with controlled morphology and crystallinity followed by the formation of BPHJ using FAPbI3 deposition by thermal evaporation technique. The BPHJ‐160 nm‐based PSCs with optimized parameters exhibit an enhanced PCE of 23.08% compared to single‐layer reference (20.15%) device. The improved performance can be attributed to the effective charge extraction at the heterojunction interface and reduced charge recombination losses due to favorable energy levels. Furthermore, the long‐term stability of the BPHJ‐based perovskite device is assessed under continuous illumination along with its ambient and thermal stability across different environmental conditions. [ABSTRACT FROM AUTHOR]

Over the last ten years, there has been a remarkable enhancement in the power conversion efficiency (PCE) of perovskite solar cells (PSCs), with poly (3,4-ethylenedioxythiohene):poly (styrenesulfonate) (PEDOT:PSS) emerging as a prevalent choice for the hole transport layer (HTL). Nevertheless, the evolution of the widely utilized PEDOT:PSS HTL has not kept pace with the swift advancements in PSC technology, attributed to its suboptimal electrical conductivity, acidic nature, and inadequate electron-blocking performance. This study presents a novel approach to enhance the HTL by introducing molybdenum oxide (MoO3) into the PEDOT:PSS, leveraging the conductivity and solution processing compatibility of MoO3. Two methods for MoO3 integration were explored: an ammonium molybdate tetrahydrate (AMT) precursor and the direct addition of MoO3 nanoparticles. The carrier dynamics of PSCs modified by MoO3 are significantly optimized. Therefore, the PCE of the device modified by AMT and molybdenum oxide is increased to 18.23 and 19.64%, respectively, and the stability of the device is also improved. This study emphasizes the potential of MoO3 in contributing to the development of more efficient and stable PSCs. [ABSTRACT FROM AUTHOR]

Perovskite light‐emitting diodes (PeLEDs) present potential applications for next‐generation displays due to their excellent luminescent properties and solution processing. The formamidinium‐caesium lead bromide (FAxCs1−xPbBr3) mixed cation strategy is one of the primary methods to achieve high‐performance of Cs‐dominate PeLEDs system. However, the inhomogeneous distribution of cations is detrimental to the photoelectronic performance of Cs‐dominated PeLEDs. Here, in mixed FA/Cs perovskite films, it is observed that Cs, Br and trace Pb elements precipitated on the surface of the perovskite films. It is found that the segregation of cations is induced by the uncontrollable crystallization process of Cs/FA cations. By introducing biuret additive, the hydrogen bonding interaction of biuret and FA cation balances crystallization rate, which therefore significantly improves the crystal quality and cations distribution of perovskite films. As a result, green PeLEDs with a high external quantum efficiency of 28.8% are obtained, and represent five times enhancement in half‐life time (T50) of 2.48 h at an initial luminance of 100 cd m−2 relative to the control device. The results help to understand the relationship between cationic distribution and PeLEDs properties, offering significant insights for modulating the performance of PeLEDs. [ABSTRACT FROM AUTHOR]

Novel perovskites pertain to newly discovered or less studied variants of the conventional perovskite structure, characterized by distinctive properties and potential for diverse applications such as ferroelectric, optoelectronic, and thermoelectric uses. In recent years, advancements in computational methods have markedly expedited the discovery and design of innovative perovskite materials, leading to numerous pertinent reports. However, there are few reviews that thoroughly elaborate the role of computational methods in studying novel perovskites, particularly for state-of-the-art perovskite categories. This review delves into the computational discovery of novel perovskite materials, with a particular focus on antiperovskites and chalcogenide perovskites. We begin with a discussion on the computational methods applied to evaluate the stability and electronic structure of materials. Next, we highlight how these methods expedite the discovery process, demonstrating how rational simulations contribute to researching novel perovskites with improved performance. Finally, we thoroughly discuss the remaining challenges and future outlooks in this research domain to encourage further investigation. We believe that this review will be highly beneficial both for newcomers to the field and for experienced researchers in computational science who are shifting their focus to novel perovskites. [ABSTRACT FROM AUTHOR]

Metal halide perovskite wafers have shown significant potential in large‐area X‐ray detection and imaging. However, a distinct difference in optical transparency between state‐of‐the‐art perovskite wafers and single crystals indicates the inferior crystal quality of perovskite wafers, which limits the performance and stability of wafer‐based X‐ray detectors. Here, nano‐sized MAPbBr3 powders are utilized to fabricate dense perovskite wafers by low‐temperature hot‐pressing with high transparency above 60% within the 552–800 nm wavelength range. Adjacent nanocrystals assemble following the ordered coalescence mechanism, resulting in the exclusion of nanoscopic pores and crystallographic reorientation. The transparent MAPbBr3 wafer‐based detectors achieve an impressively high X‐ray sensitivity of 1.14 × 105 µC Gyair−1 cm−2 and a low detection limit of 149 nGyair s−1, which is superior to opaque MAPbBr3 wafer detectors (5.64 × 104 µC Gyair−1 cm−2 and 316.7 nGyair s−1) and comparable to MAPbBr3 single‐crystal detectors. Moreover, the detectors demonstrate high uniformity and outstanding stability under continuous X‐ray irradiation of a total dose of up to 5.9 Gyair, equaling to 29 500 times posteroanterior chest examinations. The high sensitivity and low detection limit of the detectors lead to clear X‐ray imaging performance. [ABSTRACT FROM AUTHOR]

Despite the striking increase in the power conversion efficiency (PCE) of lead‐based perovskite solar cells (PSCs), their poor operational stability impedes their commercialization. Among the various factors that influence device stability, ion migration has been identified as a key driver of degradation. In this work, the focus is on studying ion migration‐induced degradation in inverted architecture PSCs, which employ either a thin polymer layer or a self‐assembled monolayer (SAM) for hole extraction. It is demonstrated that the difference in texture imposed by the use of these hole transport layers (HTL) is an important and thus far inconspicuous factor that impacts ion migration, and consequently device stability. By investigating the buried interface in detail, it is revealed that its texture has a strong impact on the vertical compositional stratification in the perovskite active layer. By monitoring bias‐induced ion migration in devices with different hole extraction layers, it is demonstrated that the smooth polymer‐based HTL results in a higher degree of ion migration than the rough SAM HTL, corresponding to a stronger degradation in the former. These results further indicate that the use of SAMs for hole extraction is a promising strategy to suppress ion migration and improve device efficiency. [ABSTRACT FROM AUTHOR]

The characteristics of the soft component and the ionic‐electronic nature in all‐inorganic CsPbI3‐xBrx perovskite typically lead to a significant number of halide vacancy defects and ions migration, resulting in a reduction in both photovoltaic efficiency and stability. Herein, we present a tailored approach in which both anion‐fixation and undercoordinated‐Pb passivation are achieved in situ during crystallization by employing a molecule derived from aniline, specifically 2‐methoxy‐5‐trifluoromethylaniline (MFA), to address the above challenges. The incorporation of MFA into the perovskite film results in a pronounced inhibition of ion migration, a significant reduction in trap density, an enhancement in grain size, an extension of charge carrier lifetime, and a more favorable alignment of energy levels. These advantageous characteristics contribute to achieving a champion power conversion efficiency (PCE) of 22.14 % for the MFA‐based CsPbI3‐xBrx perovskite solar cells (PSCs), representing the highest efficiency reported thus far for this type of inorganic metal halide perovskite solar cells, to the best of our knowledge. Moreover, the resultant PSCs exhibits higher environmental stability and photostability. This strategy is anticipated to offer significant advantages for large‐area fabrication, particularly in terms of simplicity. [ABSTRACT FROM AUTHOR]

Aiming at numerous defects at SnO2/perovskite interface and lattice mismatch in perovskite solar cells (PSCs), we design a kind of three‐dimensional (3D) molecular glue (KBF4‐TFMSA), which is derived from strong intramolecular hydrogen bonding interaction between potassium tetrafluoroborate (KBF4) and trifluoromethane‐sulfonamide (TFMSA). A remarkable efficiency of 25.8 % with negligible hysteresis and a stabilized power output of 25.0 % have been achieved, in addition, 24.57 % certified efficiency of 1 cm2 device is also obtained. Further investigation reveals that this KBF4‐TFMSA can interact with oxygen vacancies and under‐coordinated Sn(IV) from the SnO2, in the meantime, FA+ (NH2−C=NH2+) and K+ cations can be well fixed by hydrogen bonding interaction between FA+ and BF4−, and electrostatic attraction between sulfonyl oxygen and K+ ions, respectively. Thereby, FAPbI3 crystal grain sizes are increased, interfacial defects are significantly reduced while carrier extraction/ transportation is facilitated, leading to better cell performance and excellent stabilities. Non‐encapsulated devices can maintain 91 % of their initial efficiency under maximum‐power‐point (MPP) tracking while continuous illumination (~100 mW cm−2) for 1000 h, and retain 91 % of the initial efficiency after 1000 h “double 60” damp‐heat stability testing (60 °C and 60 %RH (RH, relatively humidity)). [ABSTRACT FROM AUTHOR]

2D Ruddlesden─Popper (RP) halide perovskites are attracting increasing research interest due to their enhanced stability compared to 3D perovskites. However, the quantum confinement effect of bulk organic spacers hinders the separation and transport of photo‐generated carriers. Here, a multiple aromatic ring spacer, 3‐benzothiophene methylammonium (BTMA), is developed for a new 2D RP perovskite. The BTMA spacer is demonstrated, with a significant dipole moment, can impair the influence of the quantum confinement effect, and the presence of S atoms or thiophene is favorable for enhancing the interaction between organic spacers and inorganic sheets, improving the stability of perovskites. The perovskite photodetector with BTMA as spacers displays higher device performance than the control sample with 1‐naphthalene methylammonium (NMA) as spacers. Importantly, the outstanding stability of BTMA‐based perovskite films and devices is also confirmed under moisture, heat, and illumination conditions. Combining the asymmetric coplanar nanogap electrode architecture, the photodetectors' enhanced responsivity, detectivity, and external quantum efficiency of 314 A W−1, 3.4 × 1013 Jones, and 865%, respectively, are demonstrated. Importantly, the nanogap photodetectors display promising self‐power characteristics, which makes them attractive for numerous energy‐efficient applications. The work highlights a new route toward developing high‐performance 2D RP perovskite‐based photodetectors with excellent long‐term stability. [ABSTRACT FROM AUTHOR]

Mixed lead‐tinv halide (LTH) perovskite solar cells (LTH‐PSCs) can reduce the toxicity concerns of full lead‐based PSCs and potentially optimize the bandgap to maximize efficiency. However, commonly used hole‐transporting material (HTM) 2,2′,7,7′‐tetrakis(N,N‐di‐p‐methoxyphenyl‐amine)9,9′‐spirobifluorene (Spiro‐OMeTAD) with additional dopants Li‐bis(trifluoromethanesulfonyl) imide (Li‐TFSI) and 4‐tert‐butylpyridine (t‐BP) deteriorate oxidation Sn2+ to Sn4+ leading to trap formation. Here, the study introduces a novelty Sn‐friendly HTM for Sn‐rich LTH‐PSCs, combining Spiro‐OMeTAD with 4‐Isopropyl‐4′‐methyldiphenyliodonium tetrakis(pentafluorophenyl)borate (dpi‐TPFB) as a dopant and blended with poly(3‐hexylthiophene‐2,3‐diyl) (P3HT). This blended HTM avoids the harmful effects of Li‐TFSI and t‐BP dopants and leverages the beneficial hydrophobic properties of P3HT, which predominantly resides on the surface with a face‐on orientation. This arrangement not only enhances charge transport and extraction but also improves device stability by protecting the perovskite from environmental factors. Optimizing the P3HT concentration of blended HTM achieved a PCE of 17.27%, the highest reported for n‐i‐p structured Sn‐rich mixed LTH‐PSCs. This HTM also significantly improved device stability, maintaining over 90% of the initial PCE after 3000 h of storage and 80% under maximum power point tracking (MPPT) for 550 h in the air. [ABSTRACT FROM AUTHOR]

High‐performance perovskite solar cells (PSCs) fabricated in ambient air are considered inevitable for low‐cost commercial manufacturing. However, passivating perovskite film defects and controlling the crystallization process are critical for achieving high performance in PSCs. This study proposes using the novel 2D material MBene in green antisolvent to simultaneously modulate the crystallization and passivation defects of perovskites. MBene facilitates the passivation of uncoordinated Pb2+ ions, thereby enhancing the formation energy of vacancies within the perovskite film and adjusting the energy level structure. Moreover, MBene increases nucleation sites for perovskite, significantly extending crystal growth and improving film crystallinity, thereby reducing non‐radiative recombination. Consequently, champion devices treated with MBene achieve a power conversion efficiency (PCE) of 24.22% when fabricated in air, and exhibit superior humidity and long‐term stability. Furthermore, PSCs with added MBene exhibit significant long‐term stability under various environmental conditions, including humidity and heat. The study results lay a foundation for the development of MBene materials in photovoltaics, revealing their mechanism as a new type of 2D material in perovskites, and providing new insights for industrially producing efficient and stable solar cells. [ABSTRACT FROM AUTHOR]

Perovskite photovoltaics have attracted significant attention in both academia and industry, benefiting from the superiorities of high efficiency, low cost, and simplified fabrication process. Importantly, long‐term stability is essential for practical industrialization; however, the stability challenge remains a significant impediment. Notably, stability is an essential prerequisite for practical applications. Unfortunately, as the device area increases, even to the module level, the efficiency gradually diminishes, and the stability deteriorates. This review summarizes the advances in perovskite photovoltaic technology stability from comprehensive perspectives, including the atomic‐scale, grain boundary, film morphology, interface, charge transport layer, electrode, laser etching, and module encapsulation. First, the review highlights the ongoing importance of stability in the industrialization of perovskite photovoltaics. Then, the review presents the stability challenge and explores the relationship between efficiency and stability in large‐area photovoltaic modules, shedding light on the stability issue. Later, the review explains the stability issue in terms of structure, chemistry, interfaces, device design, operation, and external environment, and proposes stability strategies ranging from the atomic‐scale to module encapsulation. Finally, the review emphasizes various improvement strategies, particularly multilevel synergistic optimization, offering fundamental guidance for the industrialization of perovskite photovoltaics. [ABSTRACT FROM AUTHOR]

The layered double perovskite microcrystals show excellent stability both under ambient condition and under X-ray irradiation, their luminescent properties and applications in X-ray imaging have been demonstrated. [Display omitted] Metal halide perovskites, as a new class of attractive and potential scintillators, are highly promising in X-ray imaging. However, their application is limited by the sensitivity to moisture and irradiation. To address this issue, we reported a 2D layered double perovskite material Cs 4 Cd 1-x Mn x Bi 2 Cl 12 that exhibits high stability both under ambient condition and under X-ray irradiation. Cs 4 Cd 1-x Mn x Bi 2 Cl 12 demonstrates superior scintillation performance, including excellent X-ray response linearity and a high light yield (∼34,450 photons/MeV). More importantly, the X-ray excited emission intensity maintains 92% and 94% of its original value after stored at ambient condition for over two years and after X-ray irradiation with a total dose of 11.4 Gy, respectively. By mixing with PDMS (polydimethylsiloxane), we have successfully produced a high-quality flexible film that can be bent freely while maintaining its excellent scintillation properties. The scintillating screen exhibits outstanding imaging ability with a spatial resolution of up to 16.7 line pairs per millimeter (lp/mm), also, the superiority of this scintillation screen in flexible X-ray imaging is demonstrated. These results indicate the huge potential of this high-stability double perovskite scintillator in X-ray imaging. [ABSTRACT FROM AUTHOR]

Perovskite can be used to prepare high-performance photodetectors due to its excellent optical properties. However, the detection range of perovskite photodetectors is mostly limited to the visible light range, restricting their further development and application. In recent years, combining perovskite with organic bulk heterojunctions to prepare photodetectors with broadband detection capability has proven to be an effective strategy. Through this approach, the response spectrum of the photodetector can be flexibly regulated, and organic compounds can improve the perovskite film quality by passivating defects and inhibit the penetration of water molecules in the air, thereby improving the device performance and stability. In this work, we propose and demonstrate the feasibility of combining MAPbI3 perovskite with PTB7-Th:COTIC-4F to prepare high-performance photodetectors with wide spectral response characteristics. With the assistance of an organic bulk heterojunction, the defects of perovskite crystals are effectively passivated, and the detection spectrum of the device is successfully extended to about 1100 nm. As a result, the responsivity achieved is 0.58 A/W, 1.19 A/W, and 1.41 A/W under laser illumination of 532 nm, 808 nm, and 980 nm, with the power density of 5 μW/cm2 at the bias voltage of −0.5 V, respectively, which is one of the best performances among vertical device structures of this type. Moreover, the stability of the final hybrid film has been greatly improved. This work provides a new approach to the preparation of high-performance and broadband perovskite photodetectors. [ABSTRACT FROM AUTHOR]

The rapid oxidation of Sn2+ in tin‐based perovskite solar cells (TPSCs) restricts their efficiency and stability have been main bottleneck towards further development. This study developed a novel strategy which utilizes thiosulfate ions (S2O32−) in the precursor solution to enable a dual‐stage reduction process. In the solution stage, thiosulfate acted as an efficacious reducing agent to reduce Sn4+ to Sn2+, meanwhile, its oxidation products were able to reduce I2 to I− during the film stage. This dual reduction ability effectively inhibited the oxidation of Sn2+ and passivated defects, further promising an excellent stability of the perovskite devices. As a result, thiosulfate‐incorporated devices achieved a high efficiency of 14.78 % with open‐circuit voltage reaching 0.96 V. The stability of the optimized devices achieved a remarkable improvement, maintaining 90 % of their initial efficiencies after 628 hours at maximum‐power‐point (MPP). The findings provid research insights and experimental data support for the sustained dynamic reduction in TPSCs. [ABSTRACT FROM AUTHOR]

The elimination of methylammonium (MA) cation from mixed tin–lead (Sn–Pb) narrow‐bandgap (NBG) perovskites is an effective approach to enhance the operational stability of all‐perovskite tandem solar cells (TSCs). Unfortunately, the uncontrolled nucleation and crystallization processes of MA‐free Sn–Pb perovskites usually lead to inferior film quality and device performance. Herein, a bimolecular crystallization modulation strategy is reported by using guanidine thiocyanate (GuaSCN) and aminoacetamide hydrochloride (AHC) together as additives to improve the film quality of MA‐free Sn–Pb perovskites. It is demonstrated that the use of bimolecular additives can effectively improve the crystallinity, increase the grain size, and induce a preferred (100) orientation for the corresponding films, leading to high‐quality absorber with considerably reduced defect density and suppressed non‐radiative recombination. In addition, the bimolecular additives can reduce the self‐p‐doping hole concentration within the perovskite films and enhance the charge extraction at the perovskite/electron transport layer interface. The modified NBG perovskite solar cells deliver a power conversion efficiency (PCE) of 22.14%. Coupled with the wide‐bandgap (WBG) subcell, the all‐perovskite TSCs give a champion certified PCE of 27.15%, which is the highest certified PCE for MA‐free all‐perovskite TSCs. Encapsulated tandem devices maintain 90% of the initial PCE after 473 h operation. [ABSTRACT FROM AUTHOR]

Naphthalene diimides (NDI) are widely serving as the skeleton to construct electron transport materials (ETMs) for optoelectronic devices. However, most of the reported NDI‐based ETMs suffer from poor interfaces with the perovskite which deteriorates the carrier extraction and device stability. Here, a representative design concept for editing the peripheral groups of NDI molecules to achieve multifunctional properties is introduced. The resulting molecule 2,7‐bis(2,2,3,3,4,4,4‐heptafluorobutyl)benzo[lmn][3,8]phenanthroline‐1,3,6,8(2H,7H)‐tetraone (NDI‐C4F) incorporated with hydrophobic fluorine units contributes to the prevention of excessive molecular aggregation, the improvement of surface wettability and the formation of strong chemical coordination with perovskite precursors. All these features favor retarding the perovskite crystallization and achieving superior buried interfaces, which subsequently promote charge collection and improve the structural compatibility between perovskite and ETMs. The corresponding PSCs based on low‐temperature processed NDI‐C4F yield a record efficiency of 23.21%, which is the highest reported value for organic ETMs in n‐i‐p PSCs. More encouragingly, the unencapsulated devices with NDI‐C4F demonstrate extraordinary stability by retaining over 90% of their initial PCEs after 2600 h in air. This work provides an alternative molecular strategy to engineer the buried interfaces and can trigger further development of organic ETMs toward reliable PSCs. [ABSTRACT FROM AUTHOR]

All‐inorganic cesium lead halide flexible perovskite solar cells (f‐PSCs) exhibit superior thermal stability compared to their organic‐inorganic hybrid counterparts. However, their flexibility and efficiency are still below‐par for practical viability. This study presents an approach involving the introduction of multifunctional molecule ammonium benzenesulfonate (ABS) to selectively etch 0D‐Cs4Pb(IBr)6 from the mixed‐dimensional perovskite film surface, to attain more contact area between the perovskite and hole transport layer for improved hole extraction and transport. It is found that the ABS molecules bind to the perovskite lattice surface via O atoms and NH4+, effectively passivating surface defects and enhancing phase stability. The hydrophobic nature of the benzene ring in ABS further contributes to operational stability, leading to high cell efficiency of 15.00%, accompanied by enhanced operational stability. Even after undergoing 60 000 flexing cycles at a curvature radius of 5 mm, the ABS‐treated f‐PSC still retains over 98.5% of its initial efficiency. This multifunctional strategy for modifying typical mixed‐dimensional perovskite compositions significantly enhances the photovoltaic performance and stability of flexible all‐inorganic f‐PSCs. [ABSTRACT FROM AUTHOR]

Metal halide perovskites have emerged as highly promising candidates for next‐generation X‐ray detectors due to their facile and low‐cost processability, high attenuation coefficient, and tunable optoelectrical properties. In this work, quasi‐2D Dion‐Jacobson (DJ) perovskites are introduced in a flat panel X‐ray imager (FPXI) for X‐ray imaging. This study demonstrates that the diammonium interlayers in DJ perovskites play a key role in enhancing structural stability, suppressing ion migration, and improving charge transport. As a result, DJ perovskite‐based X‐ray FPXIs achieve a sensitivity of 18000 µC Gyair−1 cm−2, a low detection limit of 5.7 nGyair s−1, representing performance comparable to that of state‐of‐the‐art 3D perovskite FPXIs. Thanks to the decrease in the signal crosstalk effect of the FPXIs, a high spatial resolution of 0.54 line‐pair‐per‐pixel is achieved, which is higher than that of 3D perovskite FPXIs. Remarkably, high‐quality X‐ray imaging is achieved at a total dose of 20 µGyair, which is only 1/5 of the dose typically used in commercial equipment. This work not only provides valuable insights and guidance for the fabrication of 2D DJ perovskite X‐ray detectors but also lays the groundwork for the adoption of high‐performance, stable DJ perovskite imagers as novel flat‐panel X‐ray detectors. [ABSTRACT FROM AUTHOR]

Perovskite solar cells have emerged as a potential competitor to the silicon photovoltaic technology. The most representative perovskite cells employ SnO2 and spiro‐OMeTAD as the charge‐transport materials. Despite their high efficiencies, perovskite cells with such a configuration show unsatisfactory lifespan, normally attributed to the instability of perovskites and spiro‐OMeTAD. Limited attention was paid to the influence of SnO2, an inorganic material, on device stability. Here we show that improving SnO2 with a redox interfacial modifier, cobalt hexammine sulfamate, simultaneously enhances the power‐conversion efficiency (PCE) and stability of the perovskite solar cells. Redox reactions between the bivalent cobalt complexes and oxygen lead to the formation of a graded distribution of trivalent and bivalent cobalt complexes across the surface and bulk regions of the SnO2. The trivalent cobalt complex at the top surface of SnO2 raises the concentration of (SO3NH2)− which passivates uncoordinated Pb2+ and relieves tensile stress, facilitating the formation of perovskite with improved crystallinity. Our approach enables perovskite cells with PCEs of up to 24.91 %. The devices retained 93.8 % of their initial PCEs after 1000 hours of continuous operation under maximum power point tracking. These findings showcase the potential of cobalt complexes as redox interfacial modifiers for high‐performance perovskite photovoltaics. [ABSTRACT FROM AUTHOR]

The stability issue of perovskite solar cells (PSCs) has long been of concern to researchers. Poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) is commonly used as a hole transport layer (HTL) in the inverted PSCs to achieve efficient and stable performance. However, PEDOT:PSS can corrode ITO, affecting device efficiency. Moreover, the hydrophilic nature of PEDOT:PSS compromises device stability. In this work, Poly (3-hexylthiophene-2,5-diyl) (P3HT), known for its good hydrophobicity, was used to modify the surface of PEDOT:PSS, reducing its water absorption and thereby enhancing the efficiency and stability of PSCs. The results reveal that incorporating P3HT effectively enhances the hydrophobicity of PEDOT:PSS. Furthermore, it fosters the development of large-grain perovskite film on the PEDOT:PSS/P3HT bilayer. This enhancement leads to a power conversion efficiency (PCE) of 19.78% for PSCs, with an increase by 16% than that of reference cells (17.04% of PCE). Following a duration of 1000 h, the PCE for the device modified with P3HT remains above 90%, while the PCE of the reference device is below 70%. These findings suggest that using P3HT in conjunction with PEDOT:PSS as a bilayer HTL can concurrently and proficiently improve the efficiency and stability of PSCs. [ABSTRACT FROM AUTHOR]

Perovskite-type structures have unique crystal architecture and chemical composition, which make them highly attractive for the design of solar cells. For instance, perovskite-based solar cells have been shown to perform better than silicon cells, capable of adsorbing a wide range of light wavelengths, and they can be relatively easily manufactured at a low cost. Importantly, the perovskite-based structures can also adsorb a significant amount of hydrogen atoms into their own structure; therefore, perovskite holds promise in the solid-state storage of hydrogen. It is widely expected by the scientific community that the controlled adsorption/desorption of the hydrogen atoms into/from perovskite-based structures can help to overcome the main hydrogen storage issues such as a low volumetric density and the safety concerns (i.e., the hydrogen embrittlement affects strongly the mechanical properties of metals and, as such, the storage or transport of the gaseous hydrogen in the vessels is, especially for large vessel volumes, challenging). The purpose of this review is to provide an updated overview of the recent results and studies focusing on the perovskite materials used for both solar cells and hydrogen storage applications. Particular attention is given to (i) the preparation and the achievable efficiency and stability of the perovskite solar cells and (ii) the structural, thermodynamic, and storage properties of perovskite hydrides and oxides. We show that the perovskite materials can not only reach the efficiency above current Si-based solar cells but also, due to good stability and reasonable price, can be preferable in the solid-state storage of hydrogen. Then, the future trends and directions in the research and application of perovskite in both solar cells and hydrogen storage are also highlighted. [ABSTRACT FROM AUTHOR]

The poor stability, high noise, and low detectivity (D*) of perovskite mesh nanowire (PMN) photodetectors (PDs) seriously hinder their practical applications. Here, a phenylethylamine iodine doping strategy (PIDS) is introduced to solve these problems. The PIDS leads to the formation of 2D perovskite PEA2MAx‐1PbxI3x+1 (PEA = phenylethylamine, MA = methylamine) within MAPbI3 PMN, which not only prevents water and oxygen erosion to thwart PMN degradation but also inhibits the transport of dark state carriers to reduce dark current. As a result, the noise, D*, and stability of the PMN PD are simultaneously improved. The device exhibits low noise current (7.61 × 10−15 A Hz−1/2) and high D* of 3.2 × 1014 Jones, the highest D* value for PMN PDs reported to date. Moreover, the unpacked device sustains 100% of its initial performance after 2880 h of storage in the air (45–55% humidity), enabling it as the most stable MAPbI3 perovskite micro/nanostructure PD reported to date. Furthermore, the flexible device with PIDS exhibits comparable performance to that of the rigid device as well as great mechanical stability. Finally, the flexible device with PIDS demonstrates excellent optical imaging capability and a higher precision optical imaging potential than the commercial silicon photodiode S2386. [ABSTRACT FROM AUTHOR]

In recent years, notable progress in computational density functional theory (DFT) has facilitated the collection of extensive datasets in the field of materials science. Machine learning is a crucial technique for effectively processing and analyzing these large datasets and accelerating the creation of new compounds. In this work, we employ the Extreme Gradient Boosting (XGBoost) classification algorithm to predict the crystal structure of 381 halides and oxide perovskites using 78 features. We achieved a classification accuracy of 76.62% for these materials. Subsequently, we utilized the Random Forest and XGBoost algorithms to investigate a dataset comprising 761 perovskite materials from the material project database to predict the band gap energy (best accuracy = 84.78%, mean absolute error(MAE) = 0.410 eV, root mean square error (RMSE) = 0.594 eV) and formation energy (best accuracy = 94.81%, MAE = 0.083 eV/atom, RMSE = 0.157 eV/atom), all of these prediction results based on the chemical formulas. Notably, the feature importance analysis shows the significant influence of the number of d electrons in the d orbit of the B atom on both band gap (Eg) and formation energy (EF) properties. Finally, we applied our prediction model to identify stable perovskite solar cells, achieving an accuracy of 85.18%. These findings provide valuable guidelines for the discovery of stable perovskite solar cells and help researchers tailor the composition of perovskite materials to optimize their light-harvesting capabilities, leading to higher-power conversion efficiencies. [ABSTRACT FROM AUTHOR]

A profitable approach for improving the stability of n‐i‐p planar perovskite solar cell (PSC) is developing dopant‐free hole transport materials (HTMs) with desirable intrinsic charge transport properties. In this work, by adopting a metal‐free catalytic intramolecular C─C coupling reaction, a carbazole dimer‐based fused‐ring is synthesized, and further developed a small molecular dopant‐free HTM abbreviated as NCz‐DM with appropriate energy level, excellent hole transport and film formation properties. Applied in n‐i‐p planar PSC, an impressive power conversion efficiency (PCE) of 24.0% is achieved, together with enhanced humidity, thermal and light stability, which is among the high level of ever‐reported results for PSCs utilizing small molecular dopant‐free HTM. [ABSTRACT FROM AUTHOR]

The exceptional performance and potential of 2D/3D perovskites for enhancing the efficiency and stability of perovskite solar cells (PSCs) are extensively studied. However, selecting appropriate organic ligands is critical to this process. The incorporation of suitable ligands into the 2D layer can passivate surface defects, regulate energy level alignment, and significantly improve device stability. Conversely, using unsuitable ligands not only fails to achieve the desired functions, but also negatively impacts device efficiency by hindering charge carrier transport and causing energy level mismatch issues. Therefore, exploring the selection of organic ligands based on different requirements is essential. In this review, recent studies are classified based on the chemical structure of organic ligands, analyze their application requirements, and provide suggestions for choosing optimal organic ligands to construct 2D/3D perovskites. Additionally, the feasibility and necessity of utilizing more efficient organic ligands while providing guidance for future research on 2D/3D PSCs are emphasized. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have garnered significant interest in recent years due to their high energy conversion efficiency, unique properties, low cost, and simplified fabrication process. However, the reactivity of these devices to external factors such as moisture, water, and UV light presents significant challenges for their commercial viability, potentially compromising their long-term stability and functionality. To overcome these limitations, researchers have focused on two primary strategies: surface passivation and additive engineering. Recent research developments have shown that surface passivation and additive engineering using conducting polymers (CPs), metal-organic framework materials (MOFs), and inorganic additives have significantly improved the operability of perovskite solar cells (PSCs). CPs form resilient interactions with perovskite grains, enhancing film stability through cross-link bonds. MOFs possess a unique network of functional holes that interact with multiple perovskite layers, maintaining morphology and improving interlayer charge transport. Inorganic additives suppress defects at grain boundaries, promoting the formation and growth of perovskite absorbers while providing mechanical protection. These advancements contribute to overcoming the reactivity limitations of PSCs and bring us closer to the commercialization of this technology. The review focuses on the advancements in similar materials, their passivation principles, and the resulting effects on PSC performance. Key aspects covered include the device structure, targeted defects, passivation processes, and synthesis outcomes. By providing a comprehensive overview, the review aims to assist in the selection and synthesis of novel materials. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have attracted much attention in the field of photovoltaics, due to their high power conversion efficiency (PCE) and low cost. In recent years, inverted PSCs have achieved significant advancements in PCE and operational stability. Among the strategies for optimizing PCE and lifespan of inverted PSCs, dimensional engineering plays a critical role and garners increasing attention due to its versatile functions of passivating defects, releasing residual tensile stress, strengthening structural stability, ameliorating carrier transport and extraction, and so on. Considering the importance of dimensional engineering, a comprehensive and deep understanding of 2D perovskites and 2D/3D heterojunction is definitely necessary. In this review, first, the progress of low‐dimensional perovskite light‐harvesting materials in inverted PSCs is summarized. Subsequently, the advances in constructing 2D/3D perovskite heterojunctions, including 2D/3D bulk heterojunction within perovskite materials, 2D/3D interfacial heterojunction at the interface between perovskite film and carrier transport layer, and bottom‐up 2D/3D perovskite heterojunction are discussed. The simultaneous construction of 2D/3D heterojunction at dual interfaces is highlighted. Finally, the legitimate outlook on the further development of dimensional engineering is proposed to advance the commercialization of inverted photovoltaic technology. [ABSTRACT FROM AUTHOR]

This study presents the Br‐rich in situ synthesis of blue‐emitting 2D CsPbBr3 nanoplatelets (NPLs) with various Br/Pb ratios using ZnBr2 as a Br precursor to enhance Br ion adsorption significantly. This leads to effective passivation of surface defects, particularly Pb−Br bonds, by increasing the positive charge density around Pb atoms, thus creating a stable bonding environment and reducing defect formation. Consequently, the photoluminescence quantum yield (PLQY) improves from 31.15% for a Br/Pb ratio of 2 to 87.2% for a ratio of 6. NPLs with a Br/Pb ratio of 6 also exhibit longer lifetimes (16.69 ns) and slower bleach recovery dynamics, indicating fewer non‐radiative recombination pathways and effective exciton dynamics. Additionally, NPLs with the Br/Pb ratio of 6 demonstrated better thermal stability, with an activation energy of 124.3 meV, indicating stronger exciton binding. These NPLs also exhibited enhanced stability, with UV tolerance at 43.9% and water resistance at 23.8%, making them suitable for displays and lighting. Furthermore, Br‐passivated CsPbBr3 NPLs are used as blue emitters in prototype white LEDs, achieving a wide color gamut, 126.6% of the National Television Standards Committee and 94.5% of Rec. 2020, demonstrating their potential for high‐quality lighting and advanced display technologies. [ABSTRACT FROM AUTHOR]

The challenges of instability and surface defects in CsPbBrxI3‐x nanocrystals (NCs) pose significant limitations on their potential application in high‐performance pure‐red perovskite light‐emitting diodes (PeLEDs). Herein, a synergistic strategy of divalent cation (Zn2+) doping and anion (Te2−) passivation is proposed to solve these issues. Density functional theory analysis reveals that the synergistic effect can not only reduce the formation energy of CsPbBrxI3‐x NCs but also increase theiodide vacancy defect formation energy of CsPbBrxI3‐x NCs. Consequently, the optimized Zn2+/Te2− co‐modified CsPbBrxI3‐x NCs exhibit significantly enhanced stability with a near‐unity photoluminescence efficiency. Pure‐red PeLEDs based on these CsPbBrxI3‐x NCs possess outstanding spectral stability with a maximum external quantum efficiency and luminance of 16.1% and 1397.2 cd m−2, respectively. This synergistic strategy provides a new approach for enhancing the performance of mixed halide perovskite NCs and the corresponding optoelectronic devices. [ABSTRACT FROM AUTHOR]

Lead (Pb) halide perovskite solar cells (PSCs) exhibit impressive power conversion efficiencies close to those of their silicon counterparts. However, they suffer from moisture instability and Pb safety concerns. Previous studies have endeavoured to address these issues independently, yielding minimal advancements. Here, a general nanoencapsulation platform using natural polyphenols is reported for Pb‐halide PSCs that simultaneously addresses both challenges. The polyphenol‐based encapsulant is solution‐processable, inexpensive (≈1.6 USD m−2), and requires only 5 min for the entire process, highlighting its potential scalability. The encapsulated devices with a power conversion efficiency of 20.7% retained up to 80% of their peak performance for 2000 h and up to 70% for 7000 h. Under simulated rainfall conditions, the encapsulant rich in catechol groups captures the Pb ions released from the degraded perovskites via coordination, keeping the Pb levels within the safe drinking water threshold of 15 ppb. [ABSTRACT FROM AUTHOR]

Additive engineering has emerged as a promising strategy to address the inherent instability challenges of perovskite solar cells (PSCs) in the pursuit of commercial viability. However, achieving multifunctionality using a singular additive remains a considerable challenge. In this study, a novel comb‐like multifunctional perfluoroalkyl‐g‐polyethylenimmonium iodide (FPEI·HI) as additives to the PbI2 precursor solution to facilitate the formation of high‐quality and water‐resistant perovskite films is presented. FPEI·HI establishes robust interactions with both formamidinium iodide (FAI) and PbI2, mediated by hydrogen bonding and Lewis acid‐base interactions. These interactions play a pivotal role in simultaneously passivating negative and positive charged defects within the perovskite structure. Furthermore, the inclusion of perfluoroalkyl chains serves as resilience against moisture intrusion. As a consequence of these effects, a notably high device efficiency of 24.29% is achieved, demonstrating comprehensive improvement in various photovoltaic parameters compared to the control device (22.51%). Notably, unencapsulated devices exhibit remarkable stability in high‐humidity environments, retaining 90% of their initial efficiency even after 2500 h of storage. This work underscores the efficacy of FPEI·HI as a critical enabler for enhancing the stability and efficiency of perovskite solar cells, marking a significant stride toward their commercialization. [ABSTRACT FROM AUTHOR]

Mixed‐halide perovskites are emerging as excellent photovoltaic candidates because of their tunable bandgaps for semitransparent and tandem perovskite solar cells. However, the notorious film quality originated from the rapidly downward crystallization process susceptibly propagates enormous detrimental defects, which deteriorate the photovoltaic performance and accelerate halide segregation. To address this issue, herein, a multilayer alkalis‐intercalated‐vermiculite is employed as pre‐buried interface modifier to regulate the perovskite lattice property. The matchable lattice structure between perovskite and vermiculite by forming Pb─O bond not only releases the interfacial strain during the film growth but also the embedded alkalis ions can gradually diffuse into perovskite lattice to form a favorable vertical gradient owing to the weak interlamellar van der Waals interaction, playing bis‐roles of atomical lubricant and ion‐reservoir to eliminate detrimental defects. As a result, the film quality and lattice stability is significantly improved with suppressed phase segregation for mixed‐halide perovskites, accompanying a champion efficiency of 11.42% for carbon‐based CsPbIBr2 device, 15.25% for carbon‐based CsPbI2Br device and 23.17% for p‐i‐n inverted (Cs0.05MA0.05FA0.9)Pb(I0.93Br0.07)3 cell. This work provides a new strategy on buried interface engineering for making high‐efficiency and stable perovskite platforms. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have demonstrated remarkable progress in performance in recent years, which has placed perovskite materials as the leading promising materials for future renewable energy applications. The solvent additive technique in perovskite composition is a simple but effective process used to improve the surface quality of the perovskite layers and to improve the performance and charge transport processes essential to the functions of PSCs. These additives can have a considerable effect on the topography, crystallinity, and surface properties of the perovskite active layer, ultimately influencing the stability of the PSCs. A "two-step spin coating" deposition method to make PSCs in ambient air laboratory conditions was employed. Acetonitrile (ACN) was conventionally utilized as a chemical additive to enhance the performance of PSCs. In this study, our film properties exhibited that the incorporation of ACN in the triple cation perovskite precursor led to the passivation of surface defects and a noticeable increase in the size of the crystal grains of the perovskite films, which led to enhanced stability of devices. The efficiency achieved for PSCs prepared with 10% ACN was 15.35%, which is 30% higher than devices prepared without ACN. In addition, devices prepared with ACN have shown a lower hysteresis index and more stable behavior compared to devices prepared without ACN. This work presents an easy, low-cost method for the fabrication of high performance PSCs prepared under ambient air laboratory conditions. [ABSTRACT FROM AUTHOR]

The Japan Aerospace Exploration Agency (JAXA) is planning a Space photovoltaics Demonstration eXperiment (SDX) to reveal the tolerance to the space environment of the next-generation solar cells. One of the next-generation solar cells mounted on SDX is a perovskite solar cell (PSC), which is cost-effective and has the potential for high specific power and radiation tolerance. It is necessary to clarify the long-term stability to analyze the characteristics of PSCs in orbit because SDX will be stored for months before and after launch. Therefore, we conducted three storage tests (in air, nitrogen, and low pressure) using encapsulated PSCs. Their performance was evaluated by Light I–V, Dark I–V, and EQE measurements. As a result, almost no degradation was observed at EOL (after 400 days) under all storage conditions. We found that the encapsulated PSCs mounted on SDX are highly stable. We also found that the slight degradation of P max within 4 % was due to an increase in series resistance. • The Japan Aerospace Exploration Agency is developing perovskite solar cells for use in space. • Perovskite solar cells have an issue with long-term stability; it is still unknown how stable they are in orbit in the subject mission. • We researched the long-term stability (in air, nitrogen, and low pressure) and degradation trend of perovskite solar cells in space. • We found they have high stability after 400 days of storage even though in air, and can be applied to our mission. [ABSTRACT FROM AUTHOR]

In prevailing p-i-n perovskite solar cells (PSCs), solution-processible fullerene molecules are widely used as electron-transporting layers (ETLs) but they typically suffer from poor uniformity and undesirable stability issues. Additionally, a separate bathocuproine (BCP) layer is needed to block hole transfer, increasing fabrication complexity and cost. Here, we address these limitations by developing a novel polymeric ETL (named PFBCP) synthesized by polymerizing C60 with BCP. This innovative material achieves both efficient electron transport and hole blocking, while its excellent uniformity minimizes interface recombination and enhances stability. Consequently, our blade-coated PSCs utilizing PFBCP achieve a high power conversion efficiency exceeding 22% and retain 91% of initial efficiency after 1200 h of light exposure. This development not only paves the way for commercially viable PSCs but also opens avenues for future ETL design to realize even more efficient and stable PSCs. [ABSTRACT FROM AUTHOR]

Active oxygen highly affects the efficiency and stability of perovskite solar cells (PSCs) owing to the capacity to either passivate defects or decompose perovskite lattice. To better understand the in‐depth interaction, we demonstrate for the first time that photooxidation mechanism in all‐inorganic perovskite film dominates the phase deterioration kinetics by forming superoxide species in the presence of light and oxygen, which is significantly different from that in organic‒inorganic hybrid and even tin‐based perovskites. In all‐inorganic perovskites, the superoxide species prefer to oxidize longer and weaker Pb‒I bond to PbO and I2, leaving the much stable CsPbBr3 phase. From this chemical proof‐of‐concept, we employ an organic bioactive factor, Tanshinone IIA, as a superoxide sweeper to enhance the environmental tolerance of inorganic perovskite, serving as a "skincare" agent for anti‐aging organisms. Combined with another key point on healing defective lattice, the best carbon‐based all‐inorganic CsPbI2Br solar cell delivers an efficiency as high as 15.12% and superior stability against oxygen, light, humidity, and heat attacks. This method is also applicable to enhance the efficiency of p‒i‒n inverted (Cs0.05MA0.05FA0.9)Pb(I0.93Br0.07)3 cell to 23.46%. These findings not only help us understand the perovskite decomposition mechanisms in depth but also provide a potential strategy for advanced PSC platforms. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have gained tremendous research interest recently owing to several advantages, including low material cost, facile solution processability, bandgap tunability, and alluring device efficiency. The organic formamidinium (FA) cation‐based perovskites are mainly considered as one of the potential candidates for charge carrier generation due to their excellent properties, such as bandgap and thermal stability than traditional perovskites. However, the inevitable unfavorable polymorphism (i.e., α to δ) at room temperature still forms the basis for numerous research works to allow the fabrication of a high‐quality absorber and enhances the PSCs performance. The studies to resolve the polymorphism and several contemporary techniques (e.g., passivation strategy) with several recent novel fabrication methods presented in this review form the essence of the improvements in PSCs. The absorber morphology also influences the charge‐transfer behavior and the device's lifetime. Therefore, understanding these properties is essential to improve the absorber quality and avoid many defects. This review focuses on the structure and properties of pure and mixed FA perovskites with various halides, mainly the FA cation's role in the absorber composition. And a comprehensive overview of recent FA cation‐based double, triple, and quadrupole PSCs results with proper scientific explanations to understand the device physics. [ABSTRACT FROM AUTHOR]

NiOx as a hole transport material for inverted perovskite solar cells has received great attention owing to its high transparency, low fabrication temperature, and superior stability. However, the mismatched energy levels and possible redox reactions at the NiOx/perovskite interface severely limit the performance of NiOx-based inverted perovskite solar cells. Herein, we introduce a p-type self-assembled monolayer between NiOx and perovskite layers to modify the interface and block the undesirable redox reaction between perovskite and NiOx. The self-assembled monolayer molecules all contain phosphoric acid function groups, which can be anchored onto the NiOx surface and passivate the surface defect. Moreover, the introduction of self-assembled monolayers can regulate the energy level structure of NiOx, reduce the interfacial band energy offset, and hence promote the hole transport from perovskite to NiOx layer. Consequently, the device performance is significantly enhanced in terms of both power conversion efficiency and stability. [ABSTRACT FROM AUTHOR]

The inherent defects (lead iodide inversion and iodine vacancy) in perovskites cause non‐radiative recombination and there is also ion migration, decreasing the efficiency and stability of perovskite devices. Eliminating these inherent defects is critical for achieving high‐efficiency perovskite solar cells. Herein, an organic molecule with multiple active sites (4,7‐bromo‐5,6‐fluoro‐2,1,3‐phenylpropyl thiadiazole, M4) is introduced to modify the upper interface of perovskites. When M4 interacts with the perovskite surface, the active bromine (Br) site interacts with lead (Pb) at the surface to repair iodine atomic vacancy defects. The fluorine (F) site of M4 interacts with Pb to correct octahedral crystal lattice distortions and eliminate PbI defects. Additionally, sulfur–iodine (S–I) interactions reduce I–I dimerization and eliminate IPb defects. It is also calculated that the energy level of M4 aligns with the band gap, promoting charge transfer. As a result, the perovskite devices achieve an efficiency of 25.1%, a stabilized power output (SPO) of 25.0%, a voltage of 1.19 V, and a fill factor of 85.2%. The device retains 95% of its initial efficiency after 2000 h of ageing in a nitrogen atmosphere. Thus, multi‐point cooperative passivation of surface defects provides an effective method to improve the efficiency and stability of perovskite solar cells. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid perovskite has attracted extensive research due to its excellent optoelectronic properties and is a competitive candidate material for a new generation of photodetectors. However, lateral structure photodetectors based only on perovskite active materials still present moderate performance and poor stability. Herein, lateral structure formamidinium‐based perovskite FA0.9Cs0.1PbI3 photodetectors are reported which are modified by a solution‐processed organic semiconductor 2,7‐dioctyl[1]benzothieno[3,2‐b][1]benzothiophene (C8‐BTBT) layer for improved photosensitive performance and ambient/flexibility stability. High‐mobility organic semiconductor C8‐BTBT serves as an efficient hole transport layer that fills the grain boundaries and gaps of the FA0.9Cs0.1PbI3 film, enabling rapid extraction and transport of the photo‐generated carriers from the perovskite to the electrodes, resulting in enhanced photosensitive performance of the photodetector. Compared with the original device, the C8‐BTBT‐modified photodetector exhibits dramatically improved performance with a best responsivity of 1278 mA W−1, specific detectivity of 1.58 × 1012 Jones, external quantum efficiency of 298%, and fall time of 14.09 ms, which is 10.84 times less than 152.76 ms of the pure perovskite device. Moreover, the C8‐BTBT film acts as a protective layer for the FA0.9Cs0.1PbI3 film because of its good air stability and effective coverage, which significantly improves the ambient stability of the perovskite photodetector compared with the original device, increasing photocurrent retention from 2.5% to 61.5% or 81.5% at different humidity after 6 days. Furthermore, the C8‐BTBT‐modified perovskite photodetector exhibits outstanding flexibility performance, with only a 5% reduction in photocurrent under bending and almost no change after 200 bending cycles, while those of the pristine perovskite device have degraded to ≈80% and ≈75% under the same conditions, respectively. This study provides a facile and effective solution‐processed‐based strategy for constructing high‐performance and stable perovskite photodetectors. [ABSTRACT FROM AUTHOR]

As a result of full‐scale ongoing global efforts, the power conversion efficiency (PCE) of the organic‐inorganic metal halide perovskite has skyrocketed. Unfortunately, the long‐term operational stability for commercialization standards is still lagging owing to intrinsic defects such as ion migration‐induced degradation, undercoordinated Pb2+, and shallow defects initiated by disordered crystal growth. Herein, we employed multifunctional, non‐volatile tetra‐methyl guanidine hydrochloride [TMGHCL] ionic liquid (IL) as an additive to elucidate defects' passivation effects on organic‐inorganic metal halide perovskite. More specifically, the formation of hydrogen bonds between H+ in GA+ and I− and coordinate bonding between Cl− and undercoordinated Pb2+ could significantly passivate these defects. The hypothesis was confirmed by both experimental and DFT simulations displaying that the optimized ratio of IL integration restrains ion migration, improving grains' size, and significantly elongating the carrier lifetime. Remarkably, the modified cell achieved a peak efficiency of 22.00 % with negligible hysteresis, compared to the control device's PCE of 20.12 %. In addition, the TMGHCL‐based device retains its 93.29 % efficiency after 16 days of continuous exposure to air with a relative humidity of 35±5% and temperature of 25±5 °C. This efficient approach of adding IL to perovskites absorber can produce high PCE and has strong commercialization potential. [ABSTRACT FROM AUTHOR]

Pure‐phase α‐formamidinium lead iodide (α‐FAPbI3) perovskite solar cells (PSCs) possess potential high efficiency because of suitable bandgap. However, achieving high‐quality α‐FAPbI3 films during the spin‐coating process is challenging without anti‐solvent extraction, due to the spontaneous formation of the more stable δ‐FAPbI3 phase and the complexity of multi‐component perovskite precursor solutions. Here a gel precursor with an amorphous structure to eliminate the need for anti‐solvent extraction in achieving the homogeneous and highly oriented pure‐phase α‐FAPbI3 is devised films. The incorporation of N,N′‐dimethylpropyleneurea, and alkylammonium chloride results in extended iodoplumbate clusters in the perovskite precursor solution. In situ, spectroscopic analysis reveals that the emergence of the stable amorphous gel precursor during the initial solidification stage ensures a uniform solute distribution. This effectively prevents preferentially oriented growth in the crystal phase precursor, leading to a significant enhancement in film homogeneity. As a result, power conversion efficiencies of 24.17% for the PSC, and 19.3% for the module are achieved, along with superior operational stability, retaining 96.1% of their initial efficiency after 850 h at the maximum power point tracking. These demonstrate the best performance for the reported pure‐phase α‐FAPbI3 PSCs without anti‐solvent extraction, showing great promise for scalable manufacture. [ABSTRACT FROM AUTHOR]

Charge transport layers are critical components in perovskite solar cells (PSCs) for achieving satisfied power conversion efficiencies (PCEs) and device stability. However, these layers often bring incompatible interfaces and complex fabrication, limiting the stability and scalability of PSC technology. Here an alternative strategy of salt‐based catalyzer (SBC) is proposed to regulate the heterogeneous nucleation of perovskite, which enables uniform and well‐controlled perovskite coverage directly onto the salt‐treated substrate without electron transport layers (ETLs). By carefully adjusting the cations, anions, and the thickness of SBC, high‐quality perovskite films along with superior buried interfaces suppress the carrier recombination losses and strengthen the interfacial stability, promoting the resultant device to achieve a record PCE of 23.04%, which represents the highest reported efficiency for ETL‐free PSCs. Meanwhile, the SBC technique can be well extended to large‐area, flexible, and module‐based devices. More encouragingly, the SBC‐based unencapsulated devices exhibit remarkable operational stability by retaining over 90% of initial efficiency for 1540 h under illumination and for 6312 h in an air environment. This work provides an advisable way to fabricate efficient and stable ETL‐free PSCs toward reliable and cost‐effective production. [ABSTRACT FROM AUTHOR]

Flexible perovskite solar cells (PSCs) have been rapidly developed for realistic applications such as windows and auxiliary power supplies of electronics. However, the moisture penetration through the flexible substrate films still poses a major obstacle because it can destroy the perovskite films under outdoor conditions. Unlike conventional PSCs with glass‐based encapsulation, flexible PSCs face challenges in finding suitable materials and structures that maintain flexibility while providing effective encapsulation. Simple encapsulation methods for flexible PSCs are proposed using a transparent electrode‐integrated flexible barrier (TIFB) substrate comprising silicon nitride (SiNx)/polyethylene terephthalate (PET)/indium tin oxide (ITO). A dense SiNx layer with chemical vapor deposition on ITO–PET films is deposited and a more flexible TIFB than the conventional laminated substrate owing to its thinness is achieved. TIFB shows a low water vapor transmission rate of 4.3 × 10−3 g m−2 day. Consequently, the efficiency of TIFB‐based PSCs under harsh conditions (60 °C and 90RH%) exhibits an acceptable decrease within 10% of its highest efficiency after 400 h, which is the most stable data under high temperature and humidity among existing flexible encapsulated PSCs. TIFB, as a flexible substrate, is a major candidate to protect flexible electronics and PSCs against external factors. [ABSTRACT FROM AUTHOR]

Metal halide perovskite nanocrystals (NCs) have emerged as an alternative to conventional phosphors for wide color gamut displays. However, the issues of poor stability and low emission efficiency of pure‐red CsPbBrxI3‐x NCs set an obstacle to their practical application. Herein, the synergistic effect of Mn doping and mesoporous SiO2 sealing is reported through in situ formation of Mn‐doped NCs into mesoporous SiO2 nanospheres (MnNCs@SiO2) to structurally and spatially stabilize the perovskite NCs for bright and stable pure‐red emitter. The large bonding energy of Mn‐halogen effectively suppresses the halide vacancy defects, prompting the highest photoluminescence quantum yield (PLQY) up to 84% (634 nm) among the pure‐red composite analogs. More importantly, the nanocrystal structure stability is fundamentally improved by the enhanced formation energy with Mn doping, together with the spatial isolation by SiO2 nanospheres. The MnNCs@SiO2 films exhibit impressive stabilities against high‐temperature heating, thermal cycle test, UV irradiation, water, and acid/alkali erosion, representing one of the most stable pure‐red perovskite emitters. By integrating fabricated all‐perovskite CsPbX3 single color conversion film into the liquid crystal display (LCD) modules, a wide color gamut of 128% of NTSC is achieved, enabling an excellent color rendition for high‐saturation object colors toward practical applications. [ABSTRACT FROM AUTHOR]

The protection of lead halide perovskite within a stable matrix normally leads to the loss of semiconducting properties. Here, we report the synthesis of perovskite‐ZIF glass interpenetrating networks via a cold pressing method, which allows the advantages of bright photoluminescence, high photoconductivity and environmental stability. This hybrid architecture has provided a novel design strategy for the real‐world application of perovskite‐based devices. [ABSTRACT FROM AUTHOR]