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In recent years, perovskite solar cells (PSCs) have attracted significant attention due to their excellent photoelectric properties. However, several key performance parameters of these devices still fall short of their theoretical limits. Among these parameters, the regulation of open‐circuit voltage (VOC) has been a focal point of intensive research efforts, playing a pivotal role in advancing the efficiency of PSCs. This review first provides an overview of the generation and loss mechanism of VOC. It then discusses the significance of interface engineering in VOC regulation. Recent developments in high‐efficiency PSCs realized via interface engineering have been summarized and categorized into three key areas: surface modification, interface structure optimization, and surface dimensional engineering. Finally, a comprehensive summary of past research in this domain and offered insights into the future prospects of enhancing VOC in PSCs is provided. [ABSTRACT FROM AUTHOR]

Luminescent solar concentrators (LSCs) have recently emerged as promising candidates due to their advantages in effectively collecting solar energy through large-area photovoltaic windows for reducing the cost of solar cells. Colloidal quantum dots (QDs) have been demonstrated as the preferred choice of fluorophore materials for high-performance LSCs thanks to their exceptional optical properties. Nonetheless, the use of toxic heavy metals in QDs and expensive preparation technology impede their commercialization. Herein, we demonstrate a series of quaternary ammonium-type manganese halide hybrids featuring non-toxic and highly luminescent properties, and manipulate their optical properties by varying the Mn⋯Mn distance. The optimal (BTMA)2MnBr4 (BTMA+ = benzyl trimethylammonium) material exhibits the highest photoluminescence quantum yield (PLQY) nearing 100%. In addition, the interaction between (BTMA)2MnBr4 and polyethylene oxide (PEO) enables the obtained film to display bright green light emission and exceptional transparency. Furthermore, the prepared (BTMA)2MnBr4@PEO film is constructed on the LSC (20 mm × 20 mm × 2 mm) surface as a fluorescent layer, realizing a photovoltaic conversion efficiency of 2.06% and an internal quantum efficiency of 45.33% under 1 sun AM 1.5G illumination. These results indicate the significant promise of manganese halide hybrids for large-area, efficient, and ecofriendly LSCs. [ABSTRACT FROM AUTHOR]

Polymers play a crucial role in promoting the progress of high‐performance inverted perovskite solar cells (PSCs). However, few polymers have simultaneously achieved defect passivation and device encapsulation in PSCs. Herein, a telechelic silicone polymer (poly(dimethylsiloxane‐co‐methylsiloxane acrylate) [PDMA]) is introduced, which possesses crosslinking capability to enable structure regulation through a condensation reaction. By leveraging the advantages of the polymers before and after crosslinking, a synergistic strategy of defect healing and device encapsulation for PSCs is developed via the application of the targeted polymer. PDMA as additives anchors tightly at the grain boundaries (GBs) and bridges the perovskite grains, achieving defect passivation and GBs crosslinking, increasing the efficiency of inverted PSCs from 22.32% to 24.41%. Crosslinked PDMA (CPDMA) is used as an encapsulant to encapsulate the entire device, enabling non‐destructive encapsulation at room temperature and inhibiting perovskite degradation under photothermal aging. Remarkably, the PDMA‐modified device with CPDMA encapsulation maintains 98% of its initial efficiency after 1200 h under continuous illumination at 55 ± 5 °C and retains 95% of its original efficiency after 1000 h of damp heat testing, meeting one of the IEC61215:2016 standards. [ABSTRACT FROM AUTHOR]

Radio‐photovoltaic cell is a micro nuclear battery for devices operating in extreme environments, which converts the decay energy of a radioisotope into electric energy by using a phosphor and a photovoltaic converter. Many phosphors with high light yield and good environmental stability have been developed, but the performance of radio‐photovoltaic cells remains far behind expectations in terms of power density and power conversion efficiency, because of the poor photoelectric conversion efficiency of traditional photovoltaic converters under low‐light conditions. This paper reports an radio‐photovoltaic cell based on an intrinsically stable formamidinium‐cesium perovskite photovoltaic converter exhibiting a wide light wavelength response from 300 to 800 nm, high open‐circuit voltage (VOC), and remarkable efficiency at low‐light intensity. When a He ions accelerator is adopted as a mimicked α radioisotope source with an equivalent activity of 0.83 mCi cm−2, the formamidinium‐cesium perovskite radio‐photovoltaic cell achieves a VOC of 0.498 V, a short‐circuit current (JSC) of 423.94 nA cm−2, and a remarkable power conversion efficiency of 0.886%, which is 6.6 times that of the Si reference radio‐photovoltaic cell, as well as the highest among all radio‐photovoltaic cells reported so far. This work provides a theoretical basis for enhancing the performance of radio‐photovoltaic cells. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in China, accounting for the majority of primary liver cancer cases. Liver resection is the preferred curative method for early-stage HCC. However, up to 80–85% of patients have already missed the opportunity of radical surgery due to tumor advances at the time of consultation. Conversion therapies are a series of medications and treatments for initially inoperable patients. For early-stage unresectable HCC (uHCC) patients, conversion therapies are designed to meet surgical requirements by increasing the volume of the residual liver. Meanwhile, for advanced cases, conversion therapies strive for tumor shrinkage and down-staging, creating the opportunity for liver resection or liver transplantation. This review summarizes the latest advances in conversion therapies and highlights their potential for improving the survival benefit of patients with uHCC. [ABSTRACT FROM AUTHOR]

Inorganic-organic hybrid lead halide perovskites are emerging optoelectronic materials for solar cell application. However, the toxicity concerns and poor stability largely hamper their practical applications. For these reasons, the search for "perovskite-inspired" alternatives, having the same advantages but overcoming the drawbacks of the lead-based one, has become an important sector in the field. Among the candidates, Bi3+ and Sb3+ containing materials are of great interest, due to their electronic structures resembling the Pb2+. Bismuth/antimony chalcohalides have been known for a long time as the potential absorber in photovoltaics, even if their performances are still low. Interestingly, pnictogen chalcohalides can be the stepping stone toward numerous quaternary compounds, including some perovskite structures. The understanding of the fundamental properties and the current limitations of both the starting ternary compounds and the final quaternary materials can allow the achievement of improved photovoltaic absorbers, stable, and efficient. In this review, the fundamental properties and device performances of many ternary pnictogen chalcohalides and the derived quaternary compounds are summarized, focusing on the different preparation strategies. [ABSTRACT FROM AUTHOR]

The performance of perovskite solar cells (PSCs) is negatively affected by iodine (I2) impurities generated from the oxidation of iodide ions in the perovskite precursor powder, solution, and perovskite films. In this study, the use of potassium formate (HCOOK) as a reductant to minimize the presence of detrimental I2 impurities is presented. It is demonstrated that HCOOK can effectively reduce I2 back to I− in the precursor solution as well as in the devices under external conditions. Furthermore, the introduced formate anion (HCOO−) and alkali metal cation (K+) can reduce the defect density within the perovskite film by modulating perovskite growth and passivating electronic defects, significantly prolonging the carrier lifetime and reducing the J–V hysteresis. Consequently, the maximum efficiency of the HCOOK‐doped planar n–i–p PSCs reaches 23.8%. After 1000 h of operation at maximum power point tracking under continuous 1 sun illumination, the corresponding encapsulated devices retain 94% of their initial efficiency. [ABSTRACT FROM AUTHOR]

We systematically analyzed and attempted to discuss the possibility that deficiencies of zinc or selenium were associated with the incidence and severity of COVID-19. We searched for published and unpublished articles in PubMed, Embase, Web of Science and Cochrane up to 9 February 2023. And we selected healthy individuals, mild/severe, and even deceased COVID-19 patients to analyze their serum data. Data related to 2319 patients from 20 studies were analyzed. In the mild/severe group, zinc deficiency was associated with the degree of severe disease (SMD = 0.50, 95% CI 0.32–0.68, I2 = 50.5%) and we got an Egger's test of p = 0.784; but selenium deficiency was not associated with the degree of severe disease (SMD = − 0.03, 95% CI − 0.98–0.93, I2 = 96.7%). In the surviving/death group, zinc deficiency was not associated with mortality of COVID-19 (SMD = 1.66, 95%CI − 1.42–4.47), nor was selenium (SMD = − 0.16, 95%CI − 1.33–1.01). In the risk group, zinc deficiency was positively associated with the prevalence of COVID-19 (SMD = 1.21, 95% CI 0.96–1.46, I2 = 54.3%) and selenium deficiency was also positively associated with the prevalence of it (SMD = 1.16, 95% CI 0.71–1.61, I2 = 58.3%). Currently, serum zinc and selenium deficiencies increase the incidence of COVID-19 and zinc deficiency exacerbates the disease; however, neither zinc nor selenium was associated with mortality in patients with COVID-19. Nevertheless, our conclusions may change when new clinical studies are published. [ABSTRACT FROM AUTHOR]

The long-term stability of perovskite solar cells remains one of the most important challenges for the commercialization of this emerging photovoltaic technology. Here, we adopt a non-noble metal/metal oxide/polymer multiple-barrier to suppress the halide consumption and gaseous perovskite decomposition products release with the chemically inert bismuth electrode and Al2O3/parylene thin-film encapsulation, as well as the tightly closed system created by the multiple-barrier to jointly suppress the degradation of perovskite solar cells, allowing the corresponding decomposition reactions to reach benign equilibria. The resulting encapsulated formamidinium cesium-based perovskite solar cells with multiple-barrier maintain 90% of their initial efficiencies after continuous operation at 45 °C for 5200 h and 93% of their initial efficiency after continuous operation at 75 °C for 1000 h under 1 sun equivalent white-light LED illumination. The long-term stability of perovskite solar cells remains a critical challenge for the commercialization of the technology. Here, the authors adopt a non-noble metal/metal oxide/polymer multiple-barrier to suppress device degradation, achieving long-term stability in encapsulated p-i-n devices. [ABSTRACT FROM AUTHOR]

The most employed strategies for adjusting the electrocatalytic activity and selectivity of covalent organic frameworks (COFs) in the oxygen reduction reaction involve modifying the number and placement of heteroatoms, degree of asymmetry, and molecular configuration of the building units. However, the utilization of linkage conversion, which can induce huge local structure change, has been rarely explored for achieving such goals. In this work, we present the successful conversion of imine linkages into nonsubstituted quinoline within thiazolo-[5,4-d]thiazole-based COFs via a Rh-catalyzed C–H activation strategy. This conversion resulted in improved performance in the oxygen reduction reaction, specifically the production of hydrogen peroxide with a selectivity of 61–69% in acid solution (pH = 3.1), a high production rate (106.3 mg L−1 in 100 min), and good durability. Control experiments and theoretical calculations were conducted to investigate the underlying mechanisms, indicating that the active sites could be the quinoline nitrogen and thiazole nitrogen. Furthermore, an analysis of the electronic structure revealed that the enhanced performance following linkage conversion was attributed to an increase in in-plane π electron delocalization. This delocalization induced charge redistribution around the active sites, optimizing the adsorption of oxygen intermediates. Overall, the work paves novel pathways to fine-tune the oxygen reduction reaction performance of COFs linked by imine bonds. [ABSTRACT FROM AUTHOR]

It is widely believed that excess/residual lead iodide (PbI2) can affect the performance of perovskite solar cells. Moderate PbI2 can enhance efficiency by passivating defects, while extremely active PbI2 leads to non‐negligible hysteresis effects and reduces device stability. Although several efforts are made to investigate the role of excess PbI2, its impact is still underestimated. Recent advances further demonstrate the extraordinary potential of modifying excess PbI2; however, a comprehensive study is required to obtain a deeper understanding. Herein, the important breakthroughs regarding excess PbI2 are reviewed and the mechanism of excess PbI2 in terms of efficiency and stability is rethought. In addition, the origins, verification, and regulation of residual PbI2 are summarized. [ABSTRACT FROM AUTHOR]

The operational stability of p–i–n perovskite solar cells (PSCs) is dramatically subjected to the quality of the perovskite light harvester and the interface layer atop the perovskite. Herein, a dual crosslinked functional layer strategy of using the versatile polydimethylsiloxane as an additive both in the perovskite layer and in phenyl‐C61‐butyric acid methyl ester interface layer, to improve the device tolerance against light, thermal, humidity, and bending stress, is reported. As a result, a promising power conversion efficiency of 21.6% (stabilized at 21.3%) for nickel oxide‐based p–i–n PSCs is achieved. In addition, the unencapsulated devices maintain 97% of their initial efficiencies after continuous operation under 1 sun equivalent illumination at 60 °C with maximum power point tracking for 1000 h and 80% of their initial efficiencies exposed in ambient air for 500 h. The application of the aforementioned strategy in the flexible device also improves the bending mechanical stability, of which the corresponding flexible devices maintain 85% of their initial efficiencies after 1000 cycles at a radius of 8 mm. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have attracted much attention due to their low-cost fabrication and high power conversion efficiency (PCE). However, the long-term stability issues of PSCs remain a significant bottleneck impeding their commercialization. Inverted PSCs with a p-i-n architecture are being actively researched due to their concurrent good stability and decent efficiency. In particular, the PCE of inverted PSCs has improved significantly in recent years and is now almost approaching that of n-i-p PSCs. This review summarizes recent progress in the development of high-efficiency inverted PSCs, including the development of perovskite compositions, fabrication methods, and counter electrode materials (CEMs). Notably, we highlight the development of charge transport materials (CTMs) and the effects of defect passivation strategies on the performance of inverted PSCs. Finally, we discuss the remaining issues and perspectives of high-efficiency inverted PSCs. Inverted perovskite solar cells (PSCs) with a p-i-n architecture are being actively researched due to their concurrent good stability and decent efficiency. In particular, the power conversion efficiency (PCE) of inverted PSCs has seen clear improvement in recent years and is now almost approaching that of n-i-p PSCs. Here, we systematically review recent progress in the development of high-efficiency inverted PSCs, and highlight the development of charge transport materials and the effects of defect passivation strategies on the performance of inverted PSCs, with the aim of providing constructive suggestions for the future development of inverted PSCs. [ABSTRACT FROM AUTHOR]

Wide‐bandgap perovskites have attracted much attention due to their potential application in perovskite‐based tandem solar cells, which can surpass the theoretical efficiency up‐limit of single‐junction solar cells. However, photoinduced phase segregation remains one of the most intractable impediments that deteriorate the operational stability of wide‐bandgap perovskites solar cells. Herein, the effect of a series of alkali halides additives on the photoinduced phase segregation of wide‐bandgap perovskites with the composition of FA0.8Cs0.2Pb(I0.7Br0.3)3 (FA is formamidinium) is systematically studied. By coupling in situ time‐dependent photoluminescence technique, potassium chloride (KCl) is demonstrated to be the best in suppressing the photoinduced phase segregation. The reduced iodine vacancy defects owing to supplemented chloride ions and the coupling of potassium ions with the accumulated iodide ions at the grain boundaries lead to effective suppression phase segregation. As a consequence, the KCl‐modified wide‐bandgap perovskite solar cells present a champion efficiency of 19.34%, and the devices can maintain 93% of the initial efficiency after light soaking for 500 h with maximum power point tracking under 1 sun equivalent white light‐emitting diode illumination, much superior to the reference device without KCl modification only retaining 72% of its initial efficiency. [ABSTRACT FROM AUTHOR]

With the increased power density of gallium nitride (GaN) high electron mobility transistors (HEMTs), effective cooling is required to eliminate the self-heating effect. Incorporating diamond into GaN HEMT is an alternative way to dissipate the heat generated from the active region. In this review, the four main approaches for the integration of diamond and GaN are briefly reviewed, including bonding the GaN wafer and diamond wafer together, depositing diamond as a heat-dissipation layer on the GaN epitaxial layer or HEMTs, and the epitaxial growth of GaN on the diamond substrate. Due to the large lattice mismatch and thermal mismatch, as well as the crystal structure differences between diamond and GaN, all above works face some problems and challenges. Moreover, the review is focused on the state-of-art of polycrystalline or nanocrystalline diamond (NCD) passivation layers on the topside of GaN HEMTs, including the nucleation and growth of the diamond on GaN HEMTs, structure and interface analysis, and thermal characterization, as well as electrical performance of GaN HEMTs after diamond film growth. Upon comparing three different nucleation methods of diamond on GaN, electrostatic seeding is the most commonly used pretreatment method to enhance the nucleation density. NCDs are usually grown at lower temperatures (600–800 °C) on GaN HEMTs, and the methods of "gate after growth" and selective area growth are emphasized. The influence of interface quality on the heat dissipation of capped diamond on GaN is analyzed. We consider that effectively reducing the thermal boundary resistance, improving the regional quality at the interface, and optimizing the stress–strain state are needed to improve the heat-spreading performance and stability of GaN HEMTs. NCD-capped GaN HEMTs exhibit more than a 20% lower operating temperature, and the current density is also improved, which shows good application potential. Furthermore, the existing problems and challenges have also been discussed. The nucleation and growth characteristics of diamond itself and the integration of diamond and GaN HEMT are discussed together, which can more completely explain the thermal diffusion effect of diamond for GaN HEMT and the corresponding technical problems. [ABSTRACT FROM AUTHOR]

Mixing cations in the perovskite structure has been shown to improve optoelectronic device performance and stability. In particular, CsxMA1‐xPbBr3 (MA = CH3NH3) has been used to build high‐efficiency light‐emitting diodes. Despite those advantages, little is known about the exact location of the cations in the mixed perovskite film, and how cation distribution affects device properties and stability. By using scanning tunneling microscopy , the exact atomic structure of the mixed cation CsxMA1‐xPbBr3 perovskite interface is revealed. In addition, X‐ray photoelectron spectroscopy, ultraviolet photoemission spectroscopy and inverse photoemission spectroscopy are used to study the stability and electronic properties of the CsxMA1‐xPbBr3 perovskite film. Partial substitution of MA+ by Cs+ induces a modification of the perovskite surface structure, leading to improved device stability is shown. These results provide a better understanding of the key parameters involved in the stability of mixed cation perovskite solar cells. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) are promising candidates for further photovoltaic technology. However, the instability issue remains a major obstacle hampering their commercialization. Since perovskites are sensitive to external stressors including elevated temperature, humidity, and light, and the decomposition of perovskite under these combined stressors could largely aggravate and accelerate PSCs degradation, the stability aging test under combined stressors has been recognized as the harshest and the most important requirements for PSCs stability evaluation. Herein, the degradation mechanisms of PSCs at elevated temperature, humidity, and light illumination conditions are analyzed. Further, the recent progress on improving the stability of PSCs under combined stressors including 85% relative humidity/85 °C damp heat aging test and light and elevated temperature induced degradation aging test is summarized. The predictions for the further development of effective strategies for improving the stability of PSCs are provided at the end of this review. [ABSTRACT FROM AUTHOR]

Organic ammonium salts have been widely used for defect passivation to suppress nonradiative charge recombination in perovskite solar cells (PSCs). However, they are prone to form undesirable in‐plane favored 2D perovskites with poor charge transport capability that hamper device performance. Herein, the defects passivation role of alkyldiammonium including 1.6‐hexamethylenediamine dihydriodide (HDAI2), 1,3‐propanediamine dihydriodide (PDAI2), and 1.4‐butanediamine dihydriodide (BDAI2) for formamidinium‐cesium perovskite is systematically investigated. With help of density functional theory (DFT) calculations, BDA with suitable size can synergistically passivate two defect sites on perovskite surfaces, showing the best defect passivation effect among the above three alkyldiammonium salts. Perovskite films based on BDAI2 modification are found to keep the 3D perovskite phase with considerably reduced trap‐state density, and enhanced carrier extraction. As a result, the BDAI2‐modified devices deliver impressive efficiencies of 23.1% and 20.9% for inverted PSCs on the rigid and flexible substrates, respectively. Moreover, the corresponding encapsulated rigid devices maintain 92% of the initial efficiency after operating under continuous 1‐sun illumination with the maximum power point tracking for 1000 h. Furthermore, the mechanical flexibility of the BDAI2‐modified flexible device is also improved due to the release of residual stress. [ABSTRACT FROM AUTHOR]

Lead halide‐based perovskite solar cells (PSCs) are intriguing candidates for photovoltaic technology because of their high efficiency, low cost, and simple process advantages. Owing to lead toxicity, PSCs based on partially/fully substituted Pb with tin have attracted tremendous attention, which would enable the ideal bandgap to approach the Shockley‐Queisser (S‐Q) limit. Especially, methylammonium (MA), bromide‐free, tin‐based perovskites are striking, because of the intrinsic poor stability of MA and blue shift caused by the incorporation of Br−. The first section of this review emphasizes the motivation for studying single‐junction MA, Br‐free, and Sn‐based perovskites. The film quality improvement strategies of Sn‐based perovskites, including additive, composition, dimensional, and interface engineering toward high‐efficiency devices are comprehensively overviewed. Moreover, strategies to improve stability, where shelf, thermal and operational stabilities of the devices are summarized. Finally, this review concludes with a discussion of actual limitations and future prospects for Sn‐based PSCs. [ABSTRACT FROM AUTHOR]

In the past decade, organic–inorganic hybrid perovskite solar cells (PSCs) have made unprecedented progress and recently achieved high efficiency of over 25%, comparable with commercial silicon solar cells. However, PSCs still face poor long‐term stability hindering their commercial application. Because PSCs undergo severe degradation under environmental stress factors, such as moisture, heat, light, and electrical bias. Thus, exploring and evaluating the degradation pathways of perovskites and the degradation mechanisms of PSCs is quite essential. In situ diagnostic techniques can track the real‐time changes of structure, morphology, and optoelectronic properties of the materials in the device during the degradation process. Herein, the progress on in situ characterization for understanding the degradation in PSCs is reviewed, including advanced characterization techniques in the aspects of electron microscopy, X‐Ray, and optoelectronic spectroscopy. Besides, in situ characterization tracking the degradation process of perovskite material films from typical methylamine (MA) perovskite to formamidinium (FA)–cesium (Cs) mixed‐cation perovskite and PSCs dependent on external factors is also discussed. This overview can provide a further understanding of the stability of PSCs and solve the problems on their road to commercialization. Finally, the future perspectives of in situ characterization for understanding the degradation of PSCs are provided at the end of this review. [ABSTRACT FROM AUTHOR]

Inorganic perovskite solar cells (I‐PSCs) have attracted great attention due to the high thermal stability of inorganic perovskites versus the organic–inorganic perovskites. To ensure the thermal stability of I‐PSCs, using effective and stable inorganic charge‐transporting layers (CTLs) to replace organic ones is quite desirable. The use of low‐temperature‐prepared inorganic CTLs can also lower the total cost of I‐PSCs. Herein, a general strategy to prepare high‐quality inorganic nanoparticles‐based electron transport layers (ETLs) below 70 °C by ligand exchange on top of inorganic perovskites is developed. The ETLs possess a suitable energy‐level structure, favorable conductivity, and chemical stability. Furthermore, all‐inorganic CTLs‐based CsPbI2Br I‐PSCs with p–i–n architecture are fabricated without using any thermally unstable organic components. Consequently, the as‐fabricated I‐PSCs based on CdS ETLs yielded the highest power conversion efficiency (PCE) of up to 15.04%, among the most efficient CsPbI2Br inverted PSCs. Inspiringly, the unencapsulated all‐layer‐inorganic PSCs present outstanding stabilities, which maintained 94.8% and 95.2% of their initial PCEs after aging at 85 °C in the dark and operating under continuous light illumination at 45 °C for 480 h in N2 atmosphere, respectively. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) represent a promising next‐generation photovoltaic technology considering their high efficiency and low cost. At the current stage, resolving the stability bottleneck is extremely urgent to realize PSCs' commercialization since the efficiencies of these cells are improved to a level comparable to that of crystalline silicon solar cells. Similar to other functional layers, a proper choice of the rear electrode atop the perovskite layer is equally important for achieving the device's long‐term stability. This topic has not been comprehensively reviewed before. Here, recent progress in the development of rear electrodes based on metals, carbon‐based materials, transparent conductive oxides, and conductive polymers is summarized, especially focusing on their different impacts on the device's long‐term stability and associated degradation mechanisms. In the context of practical applications, the impacts of rear electrode materials on the device's overall efficiency and cost‐effectiveness are also discussed. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have attracted great attention due to their rapidly improved power conversion efficiency (PCE), which is up to 25.5%, comparable to commercial Si-based solar cells. Currently, stability is one of the key obstacles to their commercialization. Compared with organic–inorganic PSCs with volatile organic components, all-inorganic PSCs exhibit excellent thermal stability, and thus have attracted more and more attention in recent years. Among them, PSCs based on CsPbI3 perovskite are the most eye-catching because of its ideal bandgap (1.73 eV) and excellent light absorption. Here, we systematically review strategies to improve the efficiency and stability of CsPbI3 PSCs from their early days to recent advances. The improvement mechanisms are discussed from the aspects of film formation technology, additive engineering, dimensionality engineering, doping engineering and quantum dot technology. In the end, the future development direction and obstacles of CsPbI3 PSCs are also discussed. [ABSTRACT FROM AUTHOR]

The rapid development of perovskite solar cells (PSCs) in view of efficiency during the past decade has made this emerging photovoltaic (PV) technology a promising competitor in the PV market. In the next step, PSCs need be manufactured into module scale to meet the commercialization requirements for further practical application. Demonstrations of perovskite solar modules (PSMs) and their improvements in efficiency and stability have recently become an intense area of research activities. Minimodules with the size suitable for laboratory investigation are naturally recognized as a desirable model for the study of PSMs. Herein, the recent progress and challenges in perovskite solar minimodules and the efforts to improve their scalable fabrication, efficiency, and stability are reviewed. Minimodule architectures, minimodule fabrication, and progress in the scalable deposition of perovskite and charge‐transport layers as well as minimodule encapsulation are also discussed. [ABSTRACT FROM AUTHOR]

The electron transport layer (ETL) plays a critical role in charge extraction and perovskite thin film growth in planar n–i–p heterojunction perovskite solar cells. Herein, we modulated the nucleation and growth rate of CsPbI3 crystals by using a Mo doping strategy to synthesize high-quality SnO2 crystals as an ETL nano-film in n–i–p heterojunction perovskite solar cells. We revealed that such a nano-film with low surface energy and high roughness induced by Mo doping provides seed-like nucleation sites for CsPbI3 inorganic perovskite growth, leading to improved perovskite film morphology. The charge extraction at the ETL/perovskite interface is also enhanced due to the improved energy level alignment. As a result, a high power conversion efficiency of 17.41% can be achieved under one sun irradiation for a planar n–i–p heterojunction structured CsPbI3 solar cell by using this novel Mo–SnO2 ETL. This work provides a simple pathway to simultaneously modulate CsPbI3 inorganic perovskite crystallization and interfacial charge extraction in planar heterojunction perovskite devices. [ABSTRACT FROM AUTHOR]

Organic light emitting diodes (OLEDs) employing organic thin‐film based emitters have attracted tremendous attention due to their widespread applications in lighting and as displays in mobile devices and televisions. The novel thin‐film photovoltaic techniques using organic or organic–inorganic hybrid materials such as organic photovoltaics (OPVs) and perovskite solar cells (PSCs) have become emerging competitive candidates with regard to the traditional photovoltaic techniques on account of high‐efficiency, low‐cost, and simple manufacturing processing properties. However, OLEDs, OPVs, and PSCs are vulnerable to the undesired degradation induced by moisture and oxygen. To afford long‐term stability, a robust encapsulation technique by employing materials and structures that possess high barrier performance against oxygen and moisture must be explored and employed to protect these devices. Herein, the recent progress on specific encapsulation materials and techniques for three types of devices on the basis of fundamental understanding of device stability is reviewed. First, their degradation mechanisms, as well as, influencing factors are discussed. Then, the encapsulation technologies and materials are classified and discussed. Moreover, the advantages and disadvantages of various encapsulation technologies and materials coupled with their encapsulation applications in different devices are compared. Finally, the ongoing challenges and future perspectives of encapsulation frontier are provided. [ABSTRACT FROM AUTHOR]

In addition to high efficiencies, upscaling and long‐term operational stability are key pre‐requisites for moving perovskite solar cells toward commercial applications. In this work, a strategy to fabricate large‐area uniform and dense perovskite films with a thickness over one‐micrometer via a two‐step coating process by introducing NH4Cl as an additive in the PbI2 precursor solution is developed. Incorporation of NH4Cl induces the formation of the intermediate phases of x[NH4+]·[PbI2Clx]x− and HPbI3−xClx, which can effectively retard the crystallization rate of perovskite leading to uniform and compact full‐coverage perovskite layers across large areas with high crystallinity, large grain sizes, and small surface roughness. The 5 × 5 and 10 × 10 cm2 perovskite solar modules (PSMs) based on this method achieve a power conversion efficiency (PCE) of 14.55% and 10.25%, respectively. These PSMs also exhibit good operational stability with a T80 lifetime (the time during which the solar module PCE drops to 80% of its initial value) under continuous light illumination exceeding 1600 h (5 × 5 cm2) and 1100 h (10 × 10 cm2), respectively. [ABSTRACT FROM AUTHOR]

Hybrid chemical vapor deposition (HCVD) has been employed in the fabrication of perovskite solar cells (PSCs) and modules (PSMs), and it shows strong promise for upscalable fabrication. The conventional HCVD process needs a relatively long processing time (e.g., several hours) and the fabricated PSCs often exhibit salient hysteresis, which impedes utilization of this technology for mass production. Herein, we demonstrate a rapid HCVD (RHCVD) fabrication process for PSCs using a rapid thermal process, which not only significantly reduces the deposition time to less than 10 min, but also effectively suppresses hysteresis. This markedly reduced deposition time is comparable to that of solution-coating processes. Furthermore, the shorter processing time inside the furnace reduces the exposure time of the glass/ITO/SnO2 substrates under vacuum, which helps maintain the high quality of the SnO2 electron-transport layer and results in a lower density of gap states. Finally, PSMs with a designated area of 22.4 cm2 fabricated via RHCVD achieved an efficiency of 12.3%, and maintained 90% of the initial value after operation under continuous light illumination for over 800 h. [ABSTRACT FROM AUTHOR]

Perovskite solar cells have emerged as the next‐generation high‐efficiency solar cell, but their absorption is mostly limited to the visible (vis) range. One possible solution is to integrate near‐infrared (NIR)‐to‐vis photon upconversion (UC). Herein, we show the first example of endowing perovskite solar cells with NIR sensitivity by using solid films showing NIR‐to‐vis UC based on triplet‐triplet annihilation (TTA). A high TTA‐UC efficiency of 4.1±0.3 % at an excitation intensity of 125 W/cm2 is achieved by sensitizing a rubrene (acceptor) triplet with an osmium (Os) complex donor having singlet‐to‐triplet (S−T) absorption in the NIR range, and by increasing the fluorescence quantum yield through energy harvesting to a highly fluorescent collector. In particular, our spectroscopic studies indicate that the upconverted acceptor singlet energy is almost selectively transferred to the collector rather than being quenched by the donor. By attaching the TTA‐UC film behind a semi‐transparent perovskite solar cell, a photocurrent generation is observed under excitation at 938 nm. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have attracted much attention in the past decade and their power conversion efficiency has been rapidly increasing to 25.2%, which is comparable with commercialized solar cells. Currently, the long‐term stability of PSCs remains as a major bottleneck impeding their future commercial applications. Beyond strengthening the perovskite layer itself and developing robust external device encapsulation/packaging technology, integration of effective barriers into PSCs has been recognized to be of equal importance to improve the whole device's long‐term stability. These barriers can not only shield the critical perovskite layer and other functional layers from external detrimental factors such as heat, light, and H2O/O2, but also prevent the undesired ion/molecular diffusion/volatilization from perovskite. In addition, some delicate barrier designs can simultaneously improve the efficiency and stability. In this review article, the research progress on barrier designs in PSCs for improving their long‐term stability is reviewed in terms of the barrier functions, locations in PSCs, and material characteristics. Regarding specific barriers, their preparation methods, chemical/photoelectronic/mechanical properties, and their role in device stability, are further discussed. On the basis of these accumulative efforts, predictions for the further development of effective barriers in PSCs are provided at the end of this review. [ABSTRACT FROM AUTHOR]

SUMMARY: Zinc (Zn) is an essential micronutrient for most organisms including humans, and Zn deficiency is widespread in human populations, particularly in underdeveloped regions. Cereals such as rice (Oryza sativa) are the major dietary source of Zn for most people. However, the molecular mechanism underlying Zn uptake in rice is still not fully understood. Here, we report that a member of the ZIP (ZRT, IRT‐like protein) family, OsZIP9, contributes to Zn uptake in rice. It was expressed in the epidermal and exodermal cells of lateral roots, localized in the plasma membrane and induced during Zn deficiency. Yeast‐expressed OsZIP9 showed much higher Zn influx transport activity than other rice ZIP proteins in a wide range of Zn concentrations. OsZIP9 knockout rice plants showed a significant reduction in growth at low Zn concentrations, but could be rescued by a high Zn supply. Compared with the wild type, accumulation of Zn in root, shoot and grain was much lower in knockout lines, particularly with a low supply of Zn under both hydroponic and paddy soil conditions. OsZIP9 also showed Co uptake activity. Natural variation of OsZIP9 expression level is highly associated with Zn content in milled grain among rice varieties in the germplasm collection. Taken together, these results show that OsZIP9 is an important influx transporter responsible for the take up of Zn and Co from external media into root cells. Significance Statement: Rice is the major dietary source of Zn for most people, but the underlying molecular mechanism of how rice absorbs zinc is still unclear. In this research, we characterized OsZIP9 as the major transporter responsible for zinc uptake in rice. Our work provided new insights in understanding Zn uptake in rice and strategies for improving zinc accumulation. [ABSTRACT FROM AUTHOR]

Solar cells based on metal halide perovskites have emerged as a promising low‐cost photovoltaic technology. In contrast to inert atmospheres where most of the lab‐scale devices are made to date, large‐area low‐cost production of perovskite solar cells often involves processing of perovskites in various atmospheres including ambient air, nitrogen, and/or vacuum. Herein, the impact of atmosphere on the energy levels of methylammonium lead halide perovskite films is systematically investigated. The atmosphere is varied to simulate the typical fabrication process. Through a comprehensive analysis combining the Fermi level evolution, surface photovoltage, photoluminescence properties, photovoltaic performance, and device simulation, an overall landscape of the energy diagram of the perovskite layer is able to be determined. The findings have direct implications for real‐world devices under typical atmospheres, and provide insights into the fabrication‐process design and optimization. Furthermore, a universal Fermi level shift under vacuum for lead halide‐based perovskites revealed in this study, urges a refreshed view on the energetics studies conducted without considering the atmospheric effect. [ABSTRACT FROM AUTHOR]

In the past decade, the efficiency of perovskite solar cells quickly increased from 3.8% to 25.2%. The quality of perovskite films plays vital role in device performance. The films fabricated by solution‐process are usually polycrystalline, with significantly higher defect density than that of single crystal. One kind of defect in the films is uncoordinated Pb2+, which is usually generated during thermal annealing process due to the volatile organic component. Another detrimental kind of defect is Pb0, which is often observed during the film fabrication process or solar cell operation. Because the open circuit voltage has a close relation with the defect density, it is thus desirable to passivate these two kinds of defects. Here, a molecule with multiple ligands is introduced, which not only passivates the uncoordinated Pb2+ defects, but also suppresses the formation of Pb0 defects. Meanwhile, such a treatment improves the energy level alignment between the valence band of perovskite and the highest occupied molecular orbital of spiro‐OMeTAD. As a result, the performance of perovskite solar cells significantly increases from 19.0% to 21.4%. [ABSTRACT FROM AUTHOR]

Lead-free double perovskite materials have attracted much interest for optoelectronic applications due to their nontoxicity and high stability. In this work, centimetre-sized Cs2AgBiBr6 single crystals were successfully grown using methylammonium bromide (MABr) as the flux by a top-seeded solution growth (TSSG) method. The low-temperature crystal structure of Cs2AgBiBr6 single crystals was determined and refined. To investigate the interface problems between Cs2AgBiBr6 single crystals and electrodes, the optical band gap, X-ray photoelectron spectroscopy (XPS), and ultraviolet photoemission spectroscopy (UPS) measurements were performed on Cs2AgBiBr6 single crystals. More importantly, we investigated the photodetectors based on Cs2AgBiBr6 single crystals with different contact electrodes (Au, Ag, and Al). It is found that a good Ohmic contact with Ag electrodes enables excellent photo-response behaviors. Furthermore, we studied the photodetectors based on Cs2AgBiBr6 single crystals using Ag electrodes under room and low temperature conditions, which underwent phase transition. Cs2AgBiBr6 single crystal photodetectors show clear differences at room and low temperatures, which is caused by the work function changes of Cs2AgBiBr6 single crystals induced by the reversible phase transition. These attractive properties may enable opportunities to apply emerging double perovskite single-crystalline materials for high-performance optoelectronic devices. [ABSTRACT FROM AUTHOR]

Excessive cadmium (Cd) accumulation in rice poses a potential threat to human health. Rice varieties vary in their Cd content, which depends mainly on root-to-shoot translocation of Cd. However, cultivars accumulating high Cd in the natural population have not been completely investigated. In this study, we analyzed the variation in Cd accumulation in a diverse panel of 529 rice cultivars. Only a small proportion (11 of 529) showed extremely high root-to-shoot Cd transfer rates, and in seven of these cultivars this was caused by two known OsHMA3 alleles. Using quantitative trait loci mapping, we identified a new OsHMA3 allele that was associated with high Cd accumulation in three of the remaining cultivars. Using heterologous expression in yeast and comparative analysis among different rice cultivars, we observed that this new allele was weak at both the transcriptional and protein levels compared with the functional OsHMA3 genotypes. The weak Cd transport activity was further demonstrated to be caused by a Gly to Arg substitution at position 512. Our study comprehensively analyzed the variation in root-to-shoot Cd translocation rates in cultivated rice and identified a new OsHMA3 allele that caused high Cd accumulation in a few rice cultivars. [ABSTRACT FROM AUTHOR]

This article, titled "Rear Electrode Materials for Perovskite Solar Cells," was published in Advanced Functional Materials. The authors apologize for an incorrect citation in the Figure 9a,b caption on Page 11 of the original manuscript. The corrected text provides energy band diagrams and charge kinetic behaviors of HTM-based PSCs and C-PSCs. The error does not impact the report's conclusions. The authors express regret for any inconvenience caused. The article is authored by Rui Chen, Wenjun Zhang, Xinyu Guan, Hasan Raza, Shasha Zhang, Yiqiang Zhang, Pavel A. Troshin, Sergei A. Kuklin, Zonghao Liu, and Wei Chen. [Extracted from the article]