Efficient Semi-Transparent Wide-Bandgap Perovskite Solar Cells Enabled by Pure-Chloride 2D-Perovskite Passivation

Wide-bandgap (WBG) perovskite solar cells suffer from severe non-radiative recombination and exhibit relatively large open-circuit voltage (VOC) deficits, limiting their photovoltaic performance. Here, we address these issues by in-situ forming a well-defined 2D perovskite (PMA)2PbCl4 (phenmethylammonium is referred to as PMA) passivation layer on top of the WBG active layer. The 2D layer with highly pure dimensionality and halide components is realized by intentionally tailoring the side-chain substituent at the aryl ring of the post-treatment reagent. First-principle calculation and single-crystal X-ray diffraction results reveal that weak intermolecular interactions between bulky PMA cations and relatively low cation-halide hydrogen bonding strength are crucial in forming the well-defined 2D phase. The (PMA)2PbCl4 forms improved type-I energy level alignment with the WBG perovskite, reducing the electron recombination at the perovskite/hole-transport-layer interface. Applying this strategy in fabricating semi-transparent WBG perovskite solar cells (indium tin oxide as the back electrode), the VOC deficits can be reduced to 0.49 V, comparable with the reported state-of-the-art WBG perovskite solar cells using metal electrodes. Consequently, we obtain hysteresis-free 18.60%-efficient WBG perovskite solar cells with a high VOC of 1.23 V.

Unconventional Electrochemical Behaviors of Cu Underpotential Deposition in a Chloride-Based Deep Eutectic Solvent: High Underpotential Shift and Low Coverage

The (5 × 5) Moiré pattern resulting from coadsorption of Cu atoms and chloride ions on the Au(111) electrode is one of the most classical structures for underpotential deposition (UPD) in electrochemical surface science. Although two models have been proposed to describe the pattern, the details of the structure remain ambiguous and controversial, leading to a question that remains to be answered. In this work, we investigate the UPD behaviors of Cu on the Au(111) electrode in a chloride-based deep eutectic solvent ethaline by in situ scanning tunneling microscopy (STM). Benefiting from the properties of the ultraconcentrated electrolyte, we directly image not only Cu but also Cl adlayers by finely tuning tunneling conditions. The structure is unambiguously determined for both Cu and Cl adlayers, where an incommensurate Cu layer is adsorbed on the Au(111) surface with a Cu coverage of 0.64, while the Cl coverage is 0.32 (only half of the expected value); i.e., the atomic arrangement of the observed (5 × 5) Moiré pattern in ethaline matches neither of the models proposed in the literature. Meanwhile, STM results confirm the origin of the cathodic peak in the cyclic voltammogram, which indicates that the underpotential shift of Cu UPD in ethaline indeed increases by ca. 0.40 V compared to its counterpart in a sulfuric acid solution, resulting in a significant deviation from the linear relation between the underpotential shift and the difference in work functions proposed in the literature. The unconventional electrochemical behaviors of Cu UPD reveal the specialty of both the bulk and the interface in the chloride-based deep eutectic solvent.

Well-Defined Fullerene Bisadducts Enable High-Performance Tin-Based Perovskite Solar Cells

Tin-based perovskite solar cells (TPSCs) are attracting intense research interest due to their excellent optoelectric properties and eco-friendly features. To further improve the device performance, developing new fullerene derivatives as electron transporter layers (ETLs) is highly demanded. Four well-defined regioisomers (trans-2, trans-3, trans-4, and e) of diethylmalonate-C₆₀ bisadduct (DCBA) are isolated and well characterized. The well-defined molecular structure enables us to investigate the real structure-dependent effects on photovoltaic performance. It is found that the chemical structures of the regioisomers not only affect their energy levels, but also lead to significant differences in their molecular packings and interfacial contacts. As a result, the devices with trans-2, trans-3, trans-4, and e as ETLs yield efficiencies of 11.69%, 14.58%, 12.59%, and 10.55%, respectively, which are higher than that of the as-prepared DCBA-based (10.28%) device. Notably, the trans-3-based device also demonstrates a certified efficiency of 14.30%, representing one of the best-performing TPSCs.

Determination of Clopidol Residues in Chicken Tissues by Liquid Chromatography: Collaborative Study

Eighteen laboratories participated in a collaborative study on the determination of clopidol residues in chicken muscle tissues by liquid chromatography. Of these, results from 16 laboratories which rigorously followed the method were subjected to statistical analysis. The method performance was assessed by all participants using 14 samples of chicken muscle fortified at concentrations ranging from 0.1 to 5.0 mg/kg. In addition, 9 participants each reported results for 6 clopidol-incurred samples in chicken muscle. Test portions were extracted with acetonitrile, and the extracts were purified with alumina and anion exchange resin solid-phase extraction cartridges in sequence. Clopidol was separated by reversed-phase liquid chromatography and quantified at 270 nm. Average recoveries ranged from 81.8 to 85.4%, reproducibility relative standard deviation (RSDR) ranged from 11.9 to 22.6%, and repeatability relative standard deviation (RSDr) ranged from 9.9 to 15.1%. For clopidol-incurred samples at concentrations of 0.100–0.687 mg/kg, the mean determination value range was 0.099–0.659 mg/kg; RSDR was 12.6–19.8%, RSDr was 3.1–8.5%; and HORRAT values were 0.7–1.1. The accuracy and precision of the method are in conformity with the requirements specified by AOAC INTERNATIONAL. The method was adopted Official First Action in April 2003.

Arbuscular mycorrhizal fungus alleviates alfalfa leaf spots caused by Phoma medicaginis revealed by RNA-seq analysis

AIMS

One of the major limitations to the production of alfalfa (Medicago sativa) is the fungus Phoma medicaginis, which infects alfalfa and causes leaf spots. This study aims to understand alfalfa's response to P. medicaginis infection, the colonization of arbuscular mycorrhizal fungus (AMF) and the effect of AMF on plant-pathogen interactions.

METHODS AND RESULTS

Transcriptome analysis (RNA-seq) was used to identify differentially expressed genes (DEGs) in alfalfa infected by P. medicaginis and colonized by AMF Rhizophagus intraradices. AMF ameliorated the effects of P. medicaginis infection on alfalfa by reducing leaf spot incidence and disease index by 39·48 and 56·18% respectively. Inoculation with pathogen and AMF induced the activity of defence pathways, including peroxidase (POD), polyphenol oxidase activities and jasmonic acid (JA), salicylic acid concentration. Plants showed differential expression of P. medicaginis resistance-related genes, including genes belonging to pathogenesis-related (PR) proteins, chitinase activity, flavonoid biosynthesis, phenylpropanoid biosynthesis, glutathione metabolism, phenylalanine metabolism and photosynthesis. Inoculation with AMF led to changes in the expression of genes involved in PR proteins, chitinase activity, phenylalanine metabolism and photosynthesis.

CONCLUSION

The physiological and transcriptional changes caused by P. medicaginis infection in non-mycorrhizal and mycorrhizal alfalfa provides crucial information for understanding AMF's association with pathogenic systems.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study showed that AMF alleviated alfalfa leaf spots demonstrating that AMF can serve as a biocontrol strategy for alfalfa disease management.

Fullerene derivative with a branched alkyl chain exhibits enhanced charge extraction and stability in inverted planar perovskite solar cells

Devices based on PC₆₁BEH showed an improved overall performance compared to those with PC₆₁BM as the electron transporting material.

Increased longevity and metabolic correction following syngeneic BMT in a murine model of mucopolysaccharidosis type I

Mucopolysaccharidosis type I (MPS I) is an autosomal recessive inherited disease caused by deficiency of the glycosidase α-L-iduronidase (IDUA). Deficiency of IDUA leads to lysosomal accumulation of the glycosaminoglycans (GAG) heparan and dermatan sulfate and associated multi-systemic disease, the most severe form known as Hurler syndrome. Since 1981, the treatment of Hurler patients has often included allogeneic bone marrow transplantation (BMT) from a matched donor. However, mouse models of the disease were not developed until 1997. To further characterize the MPS I mouse model and to study the effectiveness of BMT in these animals, we engrafted a cohort (n=33) of 4–8 week-old Idua^−/− animals with high levels (88.4 ± 10.3%) of wild-type donor marrow. Engrafted animals displayed an increased lifespan, preserved cardiac function, partially restored IDUA activity in peripheral organs, and decreased GAG accumulation in both peripheral organs and in the brain. However, levels of GAG and GM3 ganglioside in the brain remained elevated in comparison to unaffected animals. Since these results are similar to those observed in Hurler patients following BMT, this murine transplantation model can be used to evaluate the effects of novel, more effective methods of delivering IDUA to the brain as an adjunct to BMT.

The effects of classic antipsychotic haloperidol plus the extract of ginkgo biloba on superoxide dismutase in patients with chronic refractory schizophrenia

OBJECTIVES

To explore the association between schizophrenic symptoms and superoxide dismutase (SOD), and to investigate the effect of classic antipsychotic haloperidol plus the extract of Ginkgo biloba (EGb) on SOD.

METHODS

In 54 patients with chronic refractory schizophrenia, 27 were treated with haloperidol plus EGb (group 1), and the rest received haloperidol plus placebo (group 2). Superoxide dismutase (SOD) levels of these patients were measured before and after treatment and compared with the levels of 25 healthy volunteers. Therapeutic efficacy was equated with a change in clinical rating scores assessed by standardized measurement tools including the Scale for Assessment of Positive Symptoms (SAPS) and the Scale for Assessment of Negative Symptoms (SANS).

RESULTS

Patients in group 1 improved significantly as demonstrated by scores from both SAPS and SANS, while those in group 2 only by scores from SANS. Assessed by SAPS, the response of patients receiving haloperidol plus EGb was more significant than those receiving haloperidol only. SOD levels before treatment in all patients were significantly higher than those in normal controls. After treatment, SOD levels decreased significantly in group 1 but not in group 2. In addition, before treatment, SOD levels in all patients correlated significantly with SAPS score. The levels of SOD measured before treatment were also correlated with the improvement of patients as measured by SAPS and SANS after 12 weeks.

CONCLUSIONS

EGb may enhance the efficacy of classic antipsychotic haloperidol on schizophrenia, especially on positive symptoms. It may work through an antioxidant efficacy that is involved in the therapeutic mechanism.

Rapid and selective chelatometric titration of aluminium in non-ferrous alloys

A rapid chelatometric method for the determination of Al (4-20%) in magnesium, copper and chromium-aluminium-iron alloys is proposed. HEDTA is used as titrant and Zn solution as back-titrant, with hydrazidazol as indicator. Mn(II), Cu(II), Cd, Zn, Pb, Co(II), Ni, Hg(II), Fe(III), Bi, Cr(III), Sb(III), Ce(III), La, Sn(IV), Ti(IV), Zr and Mo(VI) do not interfere. High selectivity is achieved by a combination of group separation, masking and interference correction. The coefficient of variation varies from 0.2 to 1%.