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The rapid development of mixed‐halide perovskites has established a versatile optoelectronic platform owing to their extraordinary physical properties, but there remain challenges toward achieving highly reliable synthesis and performance, in addition, post‐synthesis approaches for tuning their photoluminescence properties after device fabrication remain limited. In this work, an effective approach is reported to leveraging hot electrons generated from plasmonic nanostructures to regulate the optical properties of perovskites. A plasmonic metasurface composed of Au nanoparticles can effectively tailor both photoluminescence and location‐specific phase segregation of mixed‐halide CsPbI2Br thin films. The ultrafast transient absorption spectroscopy measurements reveal hot electron injection on the timescale of hundreds of femtoseconds. Photocurrent measurements confirm the hot‐electron‐enhanced photon‐carrier conversion, and in addition, gate‐voltage tuning of phase segregation is observed because of correlated carrier injection and halide migration in the perovskite films. Finally, the characteristics of the gate‐modulated light emission are found to conform to a rectified linear unit function, serving as nonlinear electrical‐to‐optical converters in artificial neural networks. Overall, the hot electron engineering approach demonstrated in this work provides effective location‐specific control of the phase and optical properties of halide perovskites, underscoring the potential of plasmonic metasurfaces for advancing perovskite technologies. [ABSTRACT FROM AUTHOR]

Gas sensors are of great interest to portable and miniaturized sensing technologies with applications ranging from air quality monitoring to explosive detection and medical diagnostics, but the existing chemiresistive NO2 sensors still suffer from issues such as poor sensitivity, high operating temperature, and slow recovery. Herein, a high‐performance NO2 sensors based on all‐inorganic perovskite nanocrystals (PNCs) is reported, achieving room temperature operation with ultra‐fast response and recovery time. After tailoring the halide composition, superior sensitivity of ≈67 at 8 ppm NO2 is obtained in CsPbI2Br PNC sensors with a detection level down to 2 ppb, which outperforms other nanomaterial‐based NO2 sensors. Furthermore, the remarkable optoelectronic properties of such PNCs enable dual‐mode operation, i.e., chemiresistive and chemioptical sensing, presenting a new and versatile platform for advancing high‐performance, point‐of‐care NO2 detection technologies. [ABSTRACT FROM AUTHOR]

The all-inorganic perovskite quantum dots (QDs) and cesium lead halide QDs (CsPbBr3 QDs) are the topics of interest in the field of optoelectronic devices as they show superior photoluminescence quantum yield and tuneable optical bandgaps. However, the long-term stability issue limits their wide applications. In this research, we fabricate CsPbBr3 QDs/polymer composites through a photopolymerization strategy, during which CsPbBr3 quantum dots serve as photoinitiators in combination with the additives [diphenyliodonium hexafluorophosphate (Iod) or ethyl 4-(dimethylamino) benzoate (EDB)], to trigger polymerization processes as well as serve as highly efficient emitters in the resulted composites. More importantly, two types of additives are investigated to optimize the polymerization processes and the final product performance. In addition, steady-state photolysis, fluorescence quenching measurements, and electron spin resonance spin trapping technologies are applied to evaluate the relevant photochemical mechanism, and these demonstrate that their photoinitiation efficiency is greatly enhanced with the addition of the additives. Specifically, the addition of Iod results in higher photoinitiation ability compared to that of EDB, which can be explained by the absence of back electron donation in the CsPbBr3 QDs/Iod combination. Therefore, the strategy provided here is that CsPbBr3 QDs play a dual role in acting as both the efficient photoinitiators and the emitters to yield the desirable composites with superior photoluminescence properties, which are promising to enhance the long-term stability and device performance for the applications of luminescent displays and lighting. [ABSTRACT FROM AUTHOR]

Highlights: Research progress on inorganic perovskites quantum dots is reviewed from three aspects: physical properties, synthesis approaches, and electronic applications. Inorganic perovskite quantum dots have been exploited as either the active layers or the additives in high-performance transistors and memories. Challenges and outlook on future advancement of perovskites quantum dots-based electronics are elaborated. Metal halide perovskites have generated significant attention in recent years because of their extraordinary physical properties and photovoltaic performance. Among these, inorganic perovskite quantum dots (QDs) stand out for their prominent merits, such as quantum confinement effects, high photoluminescence quantum yield, and defect-tolerant structures. Additionally, ligand engineering and an all-inorganic composition lead to a robust platform for ambient-stable QD devices. This review presents the state-of-the-art research progress on inorganic perovskite QDs, emphasizing their electronic applications. In detail, the physical properties of inorganic perovskite QDs will be introduced first, followed by a discussion of synthesis methods and growth control. Afterwards, the emerging applications of inorganic perovskite QDs in electronics, including transistors and memories, will be presented. Finally, this review will provide an outlook on potential strategies for advancing inorganic perovskite QD technologies. [ABSTRACT FROM AUTHOR]

Ruddlesden–Popper phase 2D perovskite solar cells (PSCs) exhibit improved lifetime while still facing challenges such as phase alignment and up‐scaling to module‐level devices. Herein, polyelectrolytes are explored to tackle this issue. The contact between perovskite and hole‐transport layer (HTL) is important for decreasing interfacial non‐radiative recombination and scalable fabrication of uniform 2D perovskite films. Through exploring compatible butylamine cations, we first demonstrate poly(3‐(4‐carboxybutyl)thiophene‐2,5‐diyl)‐butylamine (P3CT‐BA) as an efficient HTL for 2D PSCs due to its great hydrophilicity, relatively high hole mobility and uniform surface. More importantly, the tailored P3CT‐BA has an anchoring effect and acts as the buried passivator for 2D perovskites. Consequently, a best efficiency approaching 18 % was achieved and we further first report large‐area (2×3 cm2, 5×5 cm2) 2D perovskite minimodules with an impressive efficiency of 14.81 % and 11.13 %, respectively. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid lead halide perovskite solar cells have made unprecedented progress in improving photovoltaic efficiency during the past decade, while still facing critical stability challenges. Herein, the natural organic dye Indigo is explored for the first time to be an efficient molecular passivator that assists in the preparation of high‐quality hybrid perovskite film with reduced defects and enhanced stability. The Indigo molecule with both carbonyl and amino groups can provide bifunctional chemical passivation for defects. In‐depth theoretical and experimental studies show that the Indigo molecules firmly binds to the perovskite surfaces, enhancing the crystallization of perovskite films with improved morphology. Consequently, the Indigo‐passivated perovskite film exhibits increased grain size with better uniformity, reduced grain boundaries, lowered defect density, and retarded ion migration, boosting the device efficiency up to 23.22%, and ≈21% for large‐area device (1 cm2). Furthermore, the Indigo passivation can enhance device stability in terms of both humidity and thermal stress. These results provide not only new insights into the multipassivation role of natural organic dyes but also a simple and low‐cost strategy to prepare high‐quality hybrid perovskite films for optoelectronic applications based on Indigo derivatives. [ABSTRACT FROM AUTHOR]

Integrating multiple semiconductors with distinct physical properties is a practical design strategy for realizing novel optoelectronic devices with unprecedented functionalities. In this work, a photonic resistive switching (RS) memory is demonstrated based on solution‐processed bilayers of strontium titanate (SrTiO3 or STO) quantum dots (QDs) and all‐inorganic halide perovskite CsPbBr3 (CPB) with an Ag/STO/CPB/Au architecture. Compared with the single‐layer STO or CPB RS device, the double‐layer device shows considerably improved RS performance with a high switching ratio over 105, an endurance of 3000 cycles, and a retention time longer than 2 × 104 s. The formation of heterojunction between STO and CPB significantly enhances the high resistance state, and the separation of the active silver electrode and the CPB layer contributes to the long‐term stability. More importantly, the photonic RS device exhibits UV–visible dual‐band response due to the photogating effect and the light‐induced modification of the heterojunction barrier. Last, tri‐mode operation, i.e., photodetector, memory, and photomemory, is demonstrated via tailoring the light and electric stimuli. This bilayer device architecture provides a unique approach toward enhancing the performance of photoresponsive data‐storage devices. [ABSTRACT FROM AUTHOR]

All‐inorganic CsPbX3 (X = Cl, Br, I, or mixed halides) perovskite quantum dots (QDs) exhibit tunable optical bandgaps and narrow emission peaks, which have received worldwide interest in the field of both photovoltaics (PVs) and light‐emitting diodes (LEDs). Herein, it is reported a discovery that CsPbI3 perovskite QD solar cell can simultaneously deliver high PV performance and intense electroluminescence. In specific, the multifunctional CsPbI3 QD film is fabricated through a simple yet efficient solid‐state‐ligand exchange process using a tailored organic ligand triphenyl phosphite (TPPI). The function of QD surface manipulation using TPPI here is proven to be twofold, balancing the carrier transport and effectively passivating the QD surface to produce conductive and emissive QD film. The CsPbI3 perovskite QD solar cell delivers a champion efficiency of 15.21% with improved open circuit voltage and high fill factor. Concurrently functioning as a red LED, the CsPbI3 perovskite QD solar cell outputs electric power to light conversion efficiency approaching 4%, a record value for QD electroluminescent PVs. The results here indicate that these versatile perovskite QDs may be a promising candidate for fabricating multifunctional optoelectronic devices. [ABSTRACT FROM AUTHOR]

Structural defects are ubiquitous for polycrystalline perovskite films, compromising device performance and stability. Herein, a universal method is developed to overcome this issue by incorporating halide perovskite quantum dots (QDs) into perovskite polycrystalline films. CsPbBr3 QDs are deposited on four types of halide perovskite films (CsPbBr3, CsPbIBr2, CsPbBrI2, and MAPbI3) and the interactions are triggered by annealing. The ions in the CsPbBr3 QDs are released into the thin films to passivate defects, and concurrently the hydrophobic ligands of QDs self‐assemble on the film surfaces and grain boundaries to reduce the defect density and enhance the film stability. For all QD‐treated films, PL emission intensity and carrier lifetime are significantly improved, and surface morphology and composition uniformity are also optimized. Furthermore, after the QD treatment, light‐induced phase segregation and degradation in mixed‐halide perovskite films are suppressed, and the efficiency of mixed‐halide CsPbIBr2 solar cells is remarkably improved to over 11% from 8.7%. Overall, this work provides a general approach to achieving high‐quality halide perovskite films with suppressed phase segregation, reduced defects, and enhanced stability for optoelectronic applications. [ABSTRACT FROM AUTHOR]

Organic‐inorganic hybrid film using conjugated materials and quantum dots (QDs) are of great interest for solution‐processed optoelectronic devices, including photovoltaics (PVs). However, it is still challenging to fabricate conductive hybrid films to maximize their PV performance. Herein, for the first time, superior PV performance of hybrid solar cells consisting of CsPbI3 perovskite QDs and Y6 series non‐fullerene molecules is demonstrated and further highlights their importance on hybrid device design. In specific, a hybrid active layer is developed using CsPbI3 QDs and non‐fullerene molecules, enabling a type‐II energy alignment for efficient charge transfer and extraction. Additionally, the non‐fullerene molecules can well passivate the QDs, reducing surface defects and energetic disorder. The champion CsPbI3 QD/Y6‐F hybrid device has a record‐high efficiency of 15.05% for QD/organic hybrid PV devices, paving a new way to construct solution‐processable hybrid film for efficient optoelectronic devices. [ABSTRACT FROM AUTHOR]

All-inorganic CsPbI3 perovskite quantum dots have received substantial research interest for photovoltaic applications because of higher efficiency compared to solar cells using other quantum dots materials and the various exciting properties that perovskites have to offer. These quantum dot devices also exhibit good mechanical stability amongst various thin-film photovoltaic technologies. We demonstrate higher mechanical endurance of quantum dot films compared to bulk thin film and highlight the importance of further research on high-performance and flexible optoelectronic devices using nanoscale grains as an advantage. Specifically, we develop a hybrid interfacial architecture consisting of CsPbI3 quantum dot/PCBM heterojunction, enabling an energy cascade for efficient charge transfer and mechanical adhesion. The champion CsPbI3 quantum dot solar cell has an efficiency of 15.1% (stabilized power output of 14.61%), which is among the highest report to date. Building on this strategy, we further demonstrate a highest efficiency of 12.3% in flexible quantum dot photovoltaics. Perovskite quantum dots film has better mechanical stability and structural integrity compared to bulk thin film. Here, the authors demonstrate higher endurance of quantum dot films and develop hybrid CsPbI3 QD/PCBM device with PCE of 15.1% and 12.3% on rigid and flexible substrates, respectively. [ABSTRACT FROM AUTHOR]

Artificial iconic memories, also called photomemories, are new types of nonvolatile memory that can simultaneously detect and store light information in a monolithic device. Several approaches have been proposed to construct artificial iconic memories, such as three-terminal field effect transistors, which can achieve an effective control of the gate voltage and external light terminals. The drawbacks in constructing these memories involve complicated fabrication processes, and the resulting performance of, for example, perovskite transistor-type photomemories is limited by the low carrier mobilities and poor ambient stabilities, whereas architectures based on floating gate modulations entail strict interface engineering and poor device reliability. In this paper, we propose a novel monolithic artificial iconic memory with a multilayer architecture of indium tin oxide/perovskite/gold/perovskite/silver, which combines the memory and photodetector functionalities of perovskites in an integrated device. The bottom perovskite layer plays the role of a photodetector, modulating the voltage bias on the top perovskite layer that serves as a resistive switching memory. This multilayer perovskite device can store photo-sensing data in its resistive states, with a memory retention of 5 × 103 s and ambient stability longer than sixty days. As a prototype demonstration, a 7 × 7 artificial iconic memory array is constructed to detect and store data on light intensity distribution, enabling a nonvolatile imaging functionality. Our work provides a new platform for designing perovskite-based architectures with simultaneous light detection and data storage capabilities. [ABSTRACT FROM AUTHOR]

Hybrid organic‐inorganic halide perovskites are actively pursued for optoelectronic technologies, but the poor stability is the Achilles' heel of these materials that hinders their applications. Very recently, it has been shown that lead sulfide (PbS) quantum dots (QDs) can form epitaxial interfaces with the perovskite matrix and enhance the overall stability. In this work, it is demonstrated that embedding QDs can significantly modify the transport property of pristine perovskite single crystals, endowing them with new functionalities besides being structurally robust and free from grain boundaries. Resistive switching memory devices are constructed using solution‐processed CH3NH3PbBr3 (MAPbBr3) perovskite single crystals and the QD‐embedded counterparts. It is found that QDs could significantly enhance the charge transport and reduce the current–voltage hysteresis. The pristine singe crystal device exhibits negative differential resistance, while the QD‐embedded crystals are featured with filament‐type switching behavior and much improved device stability. This study underscores the potential of QD‐embedded hybrid perovskites as a new media for advanced electronic devices. [ABSTRACT FROM AUTHOR]

Back Cover: Tailoring Phase Alignment and Interfaces via Polyelectrolyte Anchoring Enables Large-Area 2D Perovskite Solar Cells (Angew. 2D Perovskites, Polyelectrolytes, Ruddelsden-Popper Phase, Solar Cells The tailored polyelectrolyte has an anchoring effect and acts as a passivator for 2D perovskites, which can improve 2D perovskite phase alignment and interfacial charge transfer efficiency, and finally enables high-efficiency and large-area 2D perovskite solar cells. [Extracted from the article]

Keywords: 2D Perovskites; Polyelectrolytes; Ruddelsden-Popper Phase; Solar Cells EN 2D Perovskites Polyelectrolytes Ruddelsden-Popper Phase Solar Cells 1 1 1 09/01/22 20220905 NES 220905 B Eine Polyelektrolyt-Lochtransportschicht b für 2D-Perowskit-Solarzellen unter Verwendung eines kompatiblen Butylamin-Kations wurde von Jianyu Yuan und Mitarbeitern in ihrem Forschungsartikel untersucht (e202205111). Rücktitelbild: Tailoring Phase Alignment and Interfaces via Polyelectrolyte Anchoring Enables Large-Area 2D Perovskite Solar Cells (Angew. 2D Perovskites, Polyelectrolytes, Ruddelsden-Popper Phase, Solar Cells. [Extracted from the article]

Keywords: CsPbI 3; non-fullerene molecules; organic-inorganic hybrid solar cells; perovskite quantum dots EN CsPbI 3 non-fullerene molecules organic-inorganic hybrid solar cells perovskite quantum dots 1 1 1 07/05/21 20210702 NES 210702 In article number 2101272, Jianyu Yuan and co-workers report an efficient quantum dots (QDs)/organic hybrid system using emerging CsPbI SB 3 sb QDs and narrow bandgap Y6 series non-fullerene acceptors. Non-Fullerene Molecules: Hybrid Perovskite Quantum Dot/Non-Fullerene Molecule Solar Cells with Efficiency Over 15% (Adv. Funct. CsPbI 3, non-fullerene molecules, organic-inorganic hybrid solar cells, perovskite quantum dots. [Extracted from the article]

Hybrid halide perovskites are proposed for next-generation photovoltaics and lighting technologies due to their remarkable optoelectronic properties. In this study, we demonstrate printed perovskite nanowires (NWs) for lasing and wide-gamut phosphor using a combination of inkjet printing and nanoporous anodic aluminum oxide (AAO). The random lasing behaviors of the resulting perovskite NWs are analyzed and discussed. Moreover, by varying the composition of Cl−, Br−, and I− anions, we demonstrate tunable emission wavelengths of the perovskite NWs from 439 to 760 nm, with a large red-green-blue color space that extends to 117% of the color standard defined by the National Television Systems Committee (NTSC). Furthermore, we demonstrate passivation of the perovskite NWs against moisture due to their compact spatial confinement within the AAO template combined with a poly(methyl methacrylate) sealing process, resulting in highly stable emission intensity that degrades only 19% after continuous 250 h of 30 mW/cm2 UV excitation and degrades 30% after three months when stored in air at 50% humidity. This inkjet printing fabrication strategy involving AAO-confined perovskite NWs enables highly stable, large-area direct patterning and mass production of perovskite NWs, which is promising for modern lighting applications. Image 1 • Inkjet-printed perovskite nanowires allows easily customized patterning with controlled density, location, and feature size. • The perovskite nanowires feature tunable emission wavelengths from 439 to 760 nm with 117% of NTSC color space. • Improve the stability by compact spatial confinement, restricted expansion of perovskite nanowires, and passivation sealing. [ABSTRACT FROM AUTHOR]

In this work, STO-coated NCM811 cathode materials were obtained through a facile wet chemical method, exhibiting excellent cyclic stability. Additionally, the STO-coated NCM811 could also mitigate the Li 2 CO 3 generation on the cathode surface by effective isolation from H 2 O and CO 2. Thus, higher specific capacity was retained after long-term storage in the air compared to the uncoated NCM811 sample. Our studies proposed an effective surface modification strategy to enhance the electrochemical performance of layered ternary oxides for high performance-cathodes in commercial LIBs. [Display omitted] Ni-rich layered oxides, such as LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811), are promising cathode materials for high-energy lithium-ion batteries. However, the relatively high reactivity of Ni in NCM811 cathodes results in severe capacity fading originating from the undesired side reactions that occur at the cathode-electrolyte interface during prolonged cycling. Therefore, the trade-off between high capacity and long cycle life can obstruct the commercialization process of Ni-rich cathodes in modern lithium-ion batteries (LIBs). In addition, high sensitivity toward air upon storage greatly limits the commercial application. Herein, a facile surface modification strategy is introduced to enhance the cycling and in-air storage stability of NCM811. The NCM811 with a uniform SrTiO 3 (STO) nano-coating layer exhibited outstanding electrochemical performances that could deliver a high discharge capacity of 173.5 mAh⋅g−1 after 200 cycles under 1C with a capacity retention of 90%. In contrast, the uncoated NCM811 only provided 65% capacity retention of 130.8 mAh⋅g−1 under the same conditions. Structural evolution analysis suggested that the STO coating acted as a buffer layer to suppress the dissolution of transition metal ions caused by the HF attack from the electrolyte and promote the lithium diffusion during the charge–discharge process. In addition, the constructed STO layer prevented the exposure of NCM811 to H 2 O and CO 2 and thus effectively improved the in-air storage stability. This work offers an effective way to enhance the performance stability of Ni-rich oxides for high-performance cathodes of lithium-ion batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • Firstly, we conducted a comprehensive investigation into the crystal facet, meticulously examining the crystal facet orientation and surface atomic density of the ITO and NiO surfaces, respectively. we revealed that NiO surface exhibits less crystal facet orientations and higher metal atom density compared to ITO, suggesting that sufficient chemical binding sites for SAMs are provided to facilitate the close-packed assembly of SAMs. • Secondly, we further consider the surface roughness of ITO and ITO/NiO surfaces, respectively. NiO nanocrystals effectively reduce the surface roughness of ITO, preventing the accumulation of SAMs in ITO valleys, and facilitating the uniform distribution of SAMs. • Thirdly, based on heating and vacuum pumping experiments, we confirmed that the adhesion of − OH on the NiO is much stronger than that on the bare ITO, providing more stable assembly sites for SAMs. • Owning to the above three advantages, a more uniform, thinner, and stronger adhesion SAMs were achieved on the ITO/NiO surface compared to ITO. Finally, utilizing vacuum-assisted technology, we successfully fabricated WBG PSCs with a PCE of 19.55 % at 0.09 cm2 and a PCE of 18.74 % at 1 cm2, which are located at the top level among > 1.75 eV WBG PSCs. NiO/self-assembled monolayer (SAM) double hole transport layers (HTLs) has become the mainstream choice in high-efficiency single-junction and tandem perovskite solar cells (PSCs). However, the underlying role of NiO in double HTLs from the microscale is not systematically revealed currently. Herein, we reveal that NiO plays an important role in inducing a more uniform and thinner SAM from three aspects. Firstly, compared with indium tin oxide (ITO), the NiO surface exposes less crystal facet orientations and a higher metal atom density, suggesting that sufficient chemical binding sites for SAMs are provided to facilitate the close-packed assembly of SAMs. Secondly, NiO modified ITO exhibits smaller surficial roughness and strongly bonded −OH, which is beneficial to the uniform distribution of SAMs and strong adhesion to the NiO surface. Utilizing the well-constructed SAM, we fabricate wide-bandgap (>1.75 eV) PSCs using vacuum-assisted technology and achieve an impressive photoelectric conversion efficiency of 19.55 %. These findings not only deepen the understanding of SAM assembly on substrates but also provide essential guidance for the future industrialization of PSCs. [ABSTRACT FROM AUTHOR]