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The interaction between sites A, B and X with passivation molecules is restricted when the conventional passivation strategy is applied in perovskite (ABX3) photovoltaics. Fortunately, the revolving A-site presents an opportunity to strengthen this interaction by utilizing an external field. Herein, we propose a novel approach to achieving an ordered magnetic dipole moment, which is regulated by a magnetic field via the coupling effect between the chiral passivation molecule and the A-site (formamidine ion) in perovskites. This strategy can increase the molecular interaction energy by approximately four times and ensure a well-ordered molecular arrangement. The quality of the deposited perovskite film is significantly optimized with inhibited nonradiative recombination. It manages to reduce the open-circuit voltage loss of photovoltaic devices to 360 mV and increase the power conversion efficiency to 25.22%. This finding provides a new insight into the exploration of A-sites in perovskites and offers a novel route to improving the device performance of perovskite photovoltaics. [ABSTRACT FROM AUTHOR]

The substrates of conventional flexible perovskite solar cells (FPSCs) are thermoplastic polymer material polyethylene naphthalate (PEN), which will deform during high temperature annealing process. In addition, lead iodide (PbI2) permanently formed and the substrate undergoes reversible deformation from 20 °C to 200 °C and back to 20 °C. Therefore, to balance the substrate supporting capacity and the crystalline quality of narrow band gap α‐phase formamidinium lead iodide (α‐FAPbI3), an annealing process of 120 °C for 30 minutes is determined. Additionally, there will also be a large number of gaps and lattice strain at the perovskite grain boundaries during the annealing process as the FAPbI3 phase transition is accompanied by much lattice shrinkage. As a result, 1,6‐hexanediammonium diiodide (HADI) is chosen to passivate the defects and release the stress of perovskite film. Therefore, a recorded 1.4% extended stretch rate of the flexible film is attained. Finally, the champion PCE of 21.14% under AM 1.5G and 31.52% under 1062 lux is achieved after HADI treatment, accompanied by a better long‐term and mechanical stability. This study provides annealing process optimization and stress relief strategies for the further development of narrow band gap FPSCs. [ABSTRACT FROM AUTHOR]

Quantitative real time PCR (RT-qPCR) has emerged as an accurate and sensitive method to measure the gene expression. However, obtaining reliable result depends on the selection of reference genes which normalize differences among samples. In this study, we assessed the expression stability of seven reference genes, namely, ubiquitin-protein ligase UBC9 (UBC), tubulin alpha-5 (TUBLIN), eukaryotic translation initiation factor (EIF-5A), translation elongation factor EF1A (EF1α), translation elongation factor EF1B (EF1b), actin11 (ACTIN), and histone H3 (HIS), in Iris. lactea var. chinensis (I. lactea var. chinensis) root when the plants were subjected to cadmium (Cd), lead (Pb), and salt stress conditions. All seven reference genes showed a relatively wide range of threshold cycles (Ct) values in different samples. GeNorm and NormFinder algorithms were used to assess the suitable reference genes. The results from the two software units showed that EIF-5A and UBC were the most stable reference genes across all of the tested samples, while TUBLIN was unsuitable as internal controls. I. lactea var. chinensis is tolerant to Cd, Pb, and salt. Our results will benefit future research on gene expression in response to the three abiotic stresses.

The main reason for large energy loss in all‐inorganic perovskites is ascribed to the slow nucleation and fast crystallization of all‐inorganic perovskite films. Herein, a manipulating strategy is demonstrated to simultaneously realize rapid nucleation and slow crystal growth of CsPbI3 perovskite films by employing solvent molecular sieves in the antisolvent. First, the antisolvent treatment of mixed chlorobenzene and ethyl alcohol can induce the instantaneous supersaturation of perovskites to achieve rapid nucleation. Subsequently, the molecular layer of phthalimide (2‐N) molecules on the perovskite surface can be used as solvent molecular sieves to precisely control the evaporation of the solvent through molecule–solvent interactions. In addition, the molecules remaining on the surface can also effectively passivate the surface defects and improve the device performance. By this strategy, a synchronous regulation of rapid nucleation and slow crystal growth of perovskite films is realized for the first time. As a result, the CsPbI3 film with 2‐N treatment presents high‐quality crystallinity with large grains and less defects. The champion device exhibits an outdoor power conversion efficiency (PCE) up to 20.14% under AM1.5G illumination, and an indoor PCE up to 40.07% (Pout:133.9 µW cm–2) under a commonly used light‐emitting diode light source (2956 K, 1062 lux). [ABSTRACT FROM AUTHOR]

The effect of exogenous glutathione (GSH) and L-buthionine-S,R-sulphoximine (BSO, an inhibitor of GSH and phytochelatin (PCs) synthesis) on lead (Pb) accumulation, translocation and growth of Iris lactea var. chinensis under Pb stress were investigated. The addition of 150 mg-L-1 GSH obviously enhances Pb accumulation and translocation to shoots in I. lactea var. chinensis compared with the single Pb stress and BSO addition. The growth inhibitions were not intense after GSH treatment, even though Pb kept high accumulation in roots and shoots, suggesting that Pb may be effectively detoxified under Pb together with GSH treatment. The cell ultrastructural examination of Pb in I. lactea var. chinensis supported the facts that exogenous application of GSH may alleviate Pb harm. In order to clarify the role of non-protein thiols (NPTs) in Pb toxicity, accumulation and translocation, the dynamic variations of Pb contents and NPT synthesis of PCs, GSH and cysteine (Cys) in I. lactea var. chinensis were analyzed under Pb (100-500 mg-L-1) treatment for 1-7 days. PC2 formation could be induced only in the roots, and the contents in roots enhanced gradually with increasing Pb concentrations in solutions and exposure time. The concentrations of shoot GSH also enhanced gradually, but GSH in roots showed a slight decline when exposed to 300 and 500 mg-L-1 Pb after 4 and 7 days. Cys showed induction at lower Pb level and initial stress, followed by decline. The correlation analysis between Pb accumulation and the synthesis of NPTs suggested that Pb in the roots of I. lactea var. chinensis may mainly be detoxified through chelation with PC2. while GSH may mainly serve as the role of promoting and transporting Pb to aboveground and detoxification. [ABSTRACT FROM AUTHOR]

The present study aimed at investigating effects of lead (Pb) (30 and 300 mg L-1) stress on growth, Pb accumulation, antioxidative responses of Iris lactea var. chinensis over a 2-month period by hydroponic culture. The results show that the production rate of superoxide radical (O2-) and malondialdehyde (MDA) level in the leaves of I. lactea var. chinensis seedlings under 30 mg L-1 Pb stress remained almost unchanged, and hydrogen peroxide (H2O2) accumulation decreased as compared to the control whereas the activities of antioxidant enzymes and the contents of antioxidants investigated in shoots and roots increased. At the same time, low Pb concentrations promoted the growth of I. lactea var. chinensis seedlings. These results suggested that I. lactea var. chinensis had a strong oxidative ability to moderate Pb stress while high Pb levels (300 mg L-1) provoked oxidative stress and decreased superoxide dismutase (SOD) and peroxidase (POD) activities, especially those in the roots. In addition, high bioaccumulation of Pb was accompanied by an obvious decrease in dry weight. However, catalase (CAT) activities and glutathione (GSH) contents in shoots and roots exposed to 300 mg L-1 Pb were higher than the control. Therefore, CAT and GSH might play a major defense role in Pb detoxification when exposed to high Pb stress. [ABSTRACT FROM AUTHOR]

The effects of Pb and Zn combined stress on growth and Pb, Zn, Cu and Mn contents in the different parts of the seedlings of Iris halophila Pall, and I. pseudacorus L. were studied in pot culture. The results showed that Pb contents in the aboveground and underground parts of Iris halophila at 10 mmol·kg-1 Pb reached to 411 μg·g-1 and 2020 μg·g-1, respectively, and Zn contents, 3588 μg·g-1 and 2285 μg·g-1, respectively, at the combined treatment of 5 mmol·kg-1 Pb and 50mmol·kg-1 Zn. Pb contents in the aboveground and underground parts of I. pseudacorus at 10mmol·kg-1 Pb reached to 382μg·g-1 and 1671μg·g-1, respectively, and Zn contents, 2603μg·g-1 and 3908μg·g-1, respectively, at the combined treatment of 10mmol·kg-1 Pb and 50mmol·kg-1 Zn. Mn and Cu contents in both species presented a corresponding increase as single Pb levels enhanced and Mn contents decreased as Zn concentrations increased. The numbers and lengths of leaves and roots, and biomasses of both species were decreased significantly due to the large amount of Pb, Zn, Mn, Cu in the plants treated under 10 mmol kg-1Pb and 50 mmol kg-1Zn combined stress. The growths and developments of I. pseudacorus were effected more serious than those of I. halophilia. The negative correlation between the growth and the contents of Zn was found much more obvious than between the growth and the contents of Pb in two species of Iris L., which indicated that Zn was more toxic than that of Pb to the seedlings of I. pseudacorus and I. halophila. [ABSTRACT FROM AUTHOR]

An in situ study was conducted to evaluate the Cu up- take and distribution in two Iris L. species, namely Iris lactea var. chinensis (Fisch.) Koidz. and I. pseudacorus L. grown on abandoned tailings. The biomass and tiller were measured and the Cu contents in the different parts of plants and in the rhizosphere tailing were determined using atomic absorption spectrometer. The dry weights (DWs) of shoots, rhizomes and roots of I. lactea var. chinensis and I. pseudacorus increased significantly during growth period. New tillers of both species were formed after 150 d. Cu concentrations in roots, rhizomes and shoots of I. lactea var. chinensis were 306, 182 and 101 μg·g-1, respectively after 150d grown in the tailing. And the Cu concentrations in the roots, rhizomes and shoots of I. pseudacorus were 251, 126 and 95 μg·g-1, respectively for the same time period. The present study indicated that both I. lactea var. chinensis and I. pseudacorus could uptake Cu from the tailing effectively and the phytoremediation by using I. pseudacorus for Cu tailings worked better than I. lactea var. chinensis. [ABSTRACT FROM AUTHOR]

The seedling development and physiological responses of Iris pseudacorus L. to Pb and Cu and their combination were studied for 18 days in liquid culture. The results showed that the dry weights (DWs) of both roots and shoots decreased at 20 mg L-1 Cu and 200 mg L-1 Pb + 20 mg L-1 Cu treatments. The DWs of roots and shoots treated with 20 mg L-1Cu were dropped to 38 and 32% of the control, respectively. However, the DWs of roots and shoots did not show any significant change under single Pb treatment. The contents of total chlorophylls in the leaves treated with 200 mg L-1Pb + 20 mg L-1Cu decreased significantly compared with that of control. The cellular conductivities of the roots and shoots under 20 mg L-1Cu stress and malondialdehyde (MDA) contents in the roots and shoots in the treat-ments of 20 mg L-1Cu and 200 mg L-1 Pb + 20 mg L-1 Cu increased significantly. The superoxide dismutase (SOD) activities in the roots and shoots treated with 20 mg L-1 Cu and 200 mg L-1Pb + 20 mg L-1 Cu were significantly higher than that of the control. The proline contents in roots and shoots under 20 mg L-1 Cu mostly increased to 4 and 27 times of the control. The contents of total chlorophylls and MDA in the roots and shoots were not significantly different from the control. The results indicate that SOD and proline play important role in resisting the Cu, Pb and Cu combination stress. [ABSTRACT FROM AUTHOR]

The seedling development and physiological responses of Iris pseudacorus L. to Pb and Cd and their combination were studied for 28 days liquid culture and sub-cellular localization of Pb and Cd in the root tip cells treated with 2,070 mg L-1 Pb and 1,000 mg L-1Cd for 16 days sand culture was evaluated. Results showed that the dry weights (DWs) of shoots and roots of I. pseudacorus were significantly decreased at 500 mg L-1Pb and 25 mg L-1Cd + 500 mg L-1Pb treatments and the root DWs under all treatments were significantly decreased in comparison with that of control. The concentrations of Chla in the leaves were decreased at all treatments, while, the concentrations of Chlb and total carotenoids were not significantly decreased under 25 mg L-1Cd and 25 mg L-1Cd + 500 mg L-1Pb treatments. The MDA and proline concentrations and POD activities in the shoots and roots were increased under treatments of 500 mg L-1Pb and 25 mg L-1Cd + 500 mg L-1Pb, but POD activities in the shoots and roots and MDA concentrations in the shoots were significantly decreased at 25 mg L-1 Cd treatment. The results of sub-cellular localization of Pb and Cd showed that numerous Pb deposits were found on the inner surface of died cell walls in the cortex treated with 2,070 mg L-1 Pb and Cd deposits were found in the cell wall treated with 1,000 mg L-1 Cd. Pb and Cd deposits were not found in the cytoplasm. The results indicated that POD and proline showed strong beneficial properties against Pb and Cd stress and there were some mechanisms keeping most cells with normal activities in the plant from Pb toxicity by sacrificing a few cells that accumulated a large amount Pb. Sub-cellular localizations of Pb and Cd in the root tip cells of I. pseudacorus were little difference with the localizations in other species of Iris in the previous studies. [ABSTRACT FROM AUTHOR]

Seedling development, accumulation and distribution of lead (Pb) in Iris lactea var. chinensis (Fisch.) Koidz. and I. tectorum Maxim. were studied using plants grown in sand culture and exposed to 0-10 mmol l-1 concentrations of Pb supplied as Pb NO3)2 for 28 days. A significant reduction in dry weight (dw) of shoots and roots of I. lactea var. chinensis was observed at 6 and 10 mmol l-1, respectively, and a significant reduction in dw of shoots and roots of I. tectorum was observed at 6 mmol l-1. Concentration of Pb in the shoots and roots of I. lacteal var. chinensis exposed to 4 mmol l-1 Pb reached 1,109 µg g-1 and 2,408 µg g-1 dw, respectively. The index of tolerance (IT) of I. lactea var. chinensis among 0- 8 mmol l-1 Pb treatments were not significantly different, while those of I. tectorum at 6 mmol l-1 Pb were significantly decreased. The results indicated that I. lactea var. chinensis was more tolerant to Pb than I. tectorum. Subcellular localization of Pb in root cells was evaluated using transmission electron microscopy (TEM) and Pb deposits were found along the plasma membrane of some root tip cells of I. lactea var. chinensis treated at 10 mmol l-1 Pb. Deposits of Pd were also observed along the surface, in the root tip cell wall and in the cytoplasm of a few malformed cells of I. tectorum exposed at 10 mmol l-1 Pb treatment. One possible mechanism to explain these observations may be that most cells can maintain normal activities in the plant by sacrificing a small number of cells that accumulate a large amount Pb and show toxicity. Future studies should be designed to test this hypothesis. [ABSTRACT FROM AUTHOR]

Seedlings of Iris lactea var. chinensis (Fisch.) Koidz. and I. tectorum Maxim. were subjected to 0-160 mg l-1 Cd in hydroponic system and harvested after 42 days to determine effects on root and shoot dry mass. A subset of 16-day-old seedlings was exposed to 1000 mg l-1 Cd to characterize sub-cellular localization of Cd in root cells. The Cd contents in the shoots of I. lactea var. chinensis reached 529 µg g-1 dry weight (dw) at 80 mg l-1 Cd treatment and in the shoots of I. tectorum reached 232 µg g-1 dw at 40 mg l-1 Cd treatment, without showing signs of visible toxicity. The Cd contents in the shoots of both two test species exceeded 100 µg g-1, the critical value of Cd hyperaccumulator. The indices of tolerance (ITs) of I. lactea var. chinensis were higher than those of I. tectorum under 10-160 mg l-1Cd stress. Sub-cellular localization of Cd in root cells was evaluated using transmission electron microscopy (TEM) and Cd deposits were found in the cell walls, in the cytoplasm and on the inner surface of xylem vessels in the root tip of I. lactea var. chinensis and I. tectorum. A few cells in the root tip of I. tectorum were necrotic. The results showed that the tolerance and accumulation of Cd by I. lactea var. chinensis were higher than those of I. tectorum, suggesting that I. lactea var. chinensis has potential application in phytoremediation. [ABSTRACT FROM AUTHOR]

Perovskite light‐emitting diodes (PeLEDs) have garnered extraordinary attention in displaying field owing to their excellent luminescence properties. Although exogenous additives are extensively employed for optimizing PeLEDs, their comprehensive regulation including side effects still lacks in‐depth study. Here for the first time, it is demonstrated that the deprotonation degree of additives significantly influences the performance of blue PeLEDs. Benzenesulfonic acid (BSA) and ammonium benzenesulfonate (ABS) with similar molecular structures while distinctly different acid dissociation constants (pKa) are used for modifying blue perovskites. By comparison, high‐pKa ABS holds greater potential in boosting device performance, contributing to an improved peak external quantum efficiency of 18.8%. This discrepancy is ascribed to the fact that low‐pKa BSA is prone to induce prominent perovskite chlorine loss owing to its intense deprotonation, while high‐pKa ABS significantly suppresses chlorine vacancy formation. Meanwhile, the adsorption energy of organic spacer onto perovskite is greatly reduced due to the strong intermolecular hydrogen bonding with ABS, contributing to a concentrated phase arrangement for smooth exciton energy transfer. Additionally, ABS modification further suppresses trap‐mediated nonradiative recombination by coordinating with the undercoordinated lead (II) ions at grain boundaries. This work provides valuable guidelines for optimizing additive screening toward high‐performance blue PeLEDs. [ABSTRACT FROM AUTHOR]

Blue perovskite light‐emitting diodes (PeLEDs) are crucial avenues for achieving full‐color displays and lighting based on perovskite materials. However, the relatively low external quantum efficiency (EQE) has hindered their progression towards commercial applications. Quasi‐two‐dimensional (quasi‐2D) perovskites stand out as promising candidates for blue PeLEDs, with optimized control over low‐dimensional phases contributing to enhanced radiative properties of excitons. Herein, the impact of organic molecular dopants on the crystallization of various n‐phase structures in quasi‐2D perovskite films. The results reveal that the highly reactive bis(4‐(trifluoromethyl)phenyl)phosphine oxide (BTF‐PPO) molecule could effectively restrain the formation of organic spacer cation‐ordered layered perovskite phases through chemical reactions, simultaneously passivate those uncoordinated Pb2+ defects. Consequently, the prepared PeLEDs exhibited a maximum EQE of 16.6 % (@ 490 nm). The finding provides a new route to design dopant molecules for phase modulation in quasi‐2D PeLEDs. [ABSTRACT FROM AUTHOR]

I. lactea var. chinensis is tolerant to and accumulates cadmium (Cd), lead (Pb) and salt. The purpose of the study was to disclose the chromium(VI) impact on I. lacteavar. chinensis, and it was treated with 25 and 100 mol Cr(VI) for 4 and 8 days, respectively. The dry weight and relative water content of shoots decreased gradually as chromium concentration increased. However, superoxide dismutase (SOD) activity, malondialdehyde (MDA) content, and proline content increased whereas there was a progressive drop in chlorophyll content in both chromium treatments under both concentrations. Using electron microscopy, we observed that chloroplast shape, starch grain number and grana arrangement were all changed by chromium. Our findings provided new insights into the mechanism of chromium tolerance in Iris plants. [ABSTRACT FROM AUTHOR]

Two species of Iris L., Iris halophila Pall and I. lactea var. chinensis (Fisch.) Koidz, are halophytes. The goal of this study was to disclose the salt tolerance mechanism of I. halophila and I. lactea var. chinensis. The results showed that the contents of chlorophyll and carotenoid of two species were not significantly changed under 1.5% NaCl stress, and the dry weights (DWs) of shoot and root were increased by 28 d treatment. Using tissue anatomy, we found that root cells epidermis and the inner cortical of I. lactea var. chinensis are thick and I. halophila has developed root aerenchyma which increased respiration of roots. Moreover, there were no obvious damage changes in the chloroplast morphology and subcellular structure of two species under salt treatment. The results indicated that I. halophila and I. lactea var. chinensis are promising halophytes for the improvement of saline land. [ABSTRACT FROM AUTHOR]

Iris. lactea var. chinensis (I. lactea var. chinensis) is highly tolerant of Cu, Pb, drought, NaCl and cold. To study the molecular mechanism of I. lactea var. chinensis under these stresses, it is necessary to select reliable reference genes for RT-qPCR study. In the present study, the expression stability of nine candidate reference genes, namely, beta-tubulin (TUBLIN6), ACTIN11, translation initiation factor 4A-1 (EIF4A1), cytosolic phosphoglycerate kinase (PGK), TIP41-like family protein (TIP41), glyceraldehyde-3-phosphate dehydrogenase (GAP), phosphatase 2A (PP2Acs), cyclophilin (CYP) and ubiquitin (UBQ), was assessed in I. lactea var. chinensis plants subjected to five abiotic stresses using GeNorm and NormFinder. A combination of GAP, ACTIN11, TIP41, EIF4A1 and PGK was identified as appropriate genes for normalization under PEG stress, whereas the combination of UBQ, PGK, TIP41 and PP2Acs was the most suitable under NaCl stress. PP2Acs, ACTIN11 and UBQ exhibited the most stable expression under Pb stress. For Cu-treated leaves, CYP, GAP and TIP41 were the most stably expressed, while GAP, PP2Acs and TIP41 for cold-treated leaves. Generally, the analyses found that TIP41, CYP, PGK, GAP and PP2Acs were the most stable genes under five abiotic stress conditions. These results would contribute the more accurate and widespread use of RT-qPCR in I. lactea var. chinensis gene analysis. [ABSTRACT FROM AUTHOR]