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A new single-step and green approach for the synthesis of microcrystalline Cs2AgxNa1−xBiyIn1−yCl6 (CANBIC) perovskites in ambient conditions is introduced. The CANBIC powders emit broadband self-trapped excitonic photoluminescence (PL) with a champion PL quantum yield (QY) of 98 ± 2% and a PL lifetime of ca. 2 μs observed for x = 0.40 and y = 0.01–0.02. The study focuses on the dependence of structural, spectral, and photophysical properties of CANBICs on Bi content. CANBICs are solid solutions with isomorphous In-to-Bi substitution with the bandgap and valence band edge energy decreasing gradually with increasing y. The PL QY and the rate constant of the radiative recombination showed volcano-shaped dependences on the Bi content, while the rate of the non-radiative recombination revealed a drastic growth by three orders of magnitude as the Bi fraction y was elevated from 0.01 to 1.0 indicating that BiCl6 units are responsible for non-radiative recombination.

Thermal deposition of halide perovskites as a universal and scalable route to transparent thin films becomes highly challenging in the case of lead-free double perovskites, requiring the evaporation dynamics of multiple metal halide sources to be balanced or a single-phase precursor preliminary synthesized to achieve a reliable control over the composition and the phase of the final films. In the present Letter, the feasibility of the single-source vacuum deposition of microcrystalline Cs2AgxNa1-xBiyIn1-yCl6 double perovskites into corresponding transparent nanocrystalline films while preserving the bulk spectral and structural properties is shown. The perovskite films produced from the most emissive powders with x = 0.40 and y = 0.01 revealed a photoluminescence quantum yield of 85%, highlighting thermal evaporation as a promising approach to functional perovskite-based optical materials.

The long-term stability of perovskite solar cells remains a challenge. Both the perovskite layer and the device architecture need to endure long-term operation. Here we first use a self-constructed high-throughput screening platform to find perovskite compositions stable under heat and light. Then, we use the most stable perovskite composition to investigate the stability of contact layers in solar cells. We report on the thermal degradation mechanism of transition metal oxide contact (for example, Ta-WOx/NiOx) and propose a bilayer structure consisting of acid-doped polymer stacked on dopant-free polymer as an alternative. The dopant-free polymer provides an acid barrier between the perovskite and the acid-doped polymer. The bilayer structure exhibits stable ohmic contact at elevated temperatures and buffers iodine vapours. The unencapsulated device based on the bilayer contact (with a MgF2 capping layer) retains 99% of its peak efficiency after 1,450 h of continuous operation at 65 °C in a N2 atmosphere under metal-halide lamps. The device also shows negligible hysteresis during the entire ageing period.

Perovskite materials have a great variety of applications, such as X‐ray detection, lasing and piezoelectric, or solar energy harvesting. While achieving record efficiencies, perovskite solar cells suffer from the presence of toxic lead in their crystal structure. One possibility to circumvent this issue is via the family of vacancy‐ordered double‐perovskites, where lead atoms are replaced alternatingly by a tetravalent atom and a vacant lattice site. From this material family, Cs2TiBr6 has recently emerged as a promising candidate due to its favorable reported properties for photovoltaic applications specifically. This paper presents a novel and facile synthesis route to obtain phase‐pure Cs2TiBr6 and its lesser‐studied iodine‐based relatives Cs2TiBr4I2, Cs2TiBr2I4, and Cs2TiI6 via high‐energy mechanochemical ball milling. The materials are characterized with structural, microscopic, and photophysical techniques to reveal indirect bandgaps with values of 1.88, 1.13, 1.04, and 1.02 eV but also a distinct lack of any significant photoluminescence (PL) and a high instability under ambient conditions. These findings enable us to clarify the previously controversial properties of Cs2TiBr6 and establish its role in the vast landscape of perovskite photovoltaics.

The effect of spontaneous alloying of non-stoichiometric aqueous Ag-In-S (AIS) and Cu-In-S (CIS) quantum dots (QDs) stabilized by surface glutathione (GSH) complexes was observed spectroscopically due to the phenomenon of band bowing typical for the solid-solution Cu(Ag)-In-S (CAIS) QDs. The alloying was found to occur even at room temperature and can be accelerated by a thermal treatment of colloidal mixtures at around 90 °C with no appreciable differences in the average size observed between alloyed and original individual QDs. An equilibrium between QDs and molecular and clustered metal-GSH complexes, which can serve as "building material" for the new mixed CAIS QDs, during the spontaneous alloying is assumed to be responsible for this behavior of GSH-capped ternary QDs. The alloying effect is expected to be of a general character for different In-based ternary chalcogenides.

Quasi-2D metal-halide perovskites with Ruddlesden−Popper structures have shown promising stability due to the protectiveeffects of the intercalating organic cations. However, a systematic studyof the effect of intercalating organic cations on stability has rarely beenreported. Here we use a high-throughput-robot platform to fabricateover 300 perovskite films and study the effect of cations and theirconcentrations on the thermal stability of perovskite films. We find thatapproximately 20−25 mol % of intercalating organic cations intoMAPbI3 (nominal n = 4/5) can maximize the film stability, whilehigher/lower concentrations lead to inferior stability, which is termedstability bowing in analogy to band-gap bowing. A model with twocompetitive effects of the intercalating organic cation (better protectionvs more defects) is proposed to rationalize this behavior. We anticipatethis work to provide new insights into the stability of quasi-2Dperovskites.

The feasibility of a high-throughput robot-assisted synthesis of complex Cu1-xAgxInSySe1-x (CAISSe) quantum dots (QDs) by spontaneous alloying of aqueous glutathione-capped Ag–In–S, Cu–In–S, Ag–In–Se, and Cu–In–Se QDs is demonstrated. Both colloidal and thin-film core CAISSe and core/shell CAISSe/ZnS QDs are produced and studied by high-throughput semiautomated photoluminescence (PL) spectroscopy. The silver-copper-mixed QDs reveal clear evidence of a band bowing effect in the PL spectra and higher average PL lifetimes compared to the counterparts containing silver or copper only. The photophysical analysis of CAISSe and CAISSe/ZnS QDs indicates a composition-dependent character of the nonradiative recombination in QDs. The rate of this process is found to be lower for mixed copper-silver-based QDs compared to Cu- or Ag-only QDs. The combination of the band bowing effect and the suppressed nonradiative recombination of CAISSe QDs is beneficial for their applications in photovoltaics and photochemistry. The synergy of high-throughput robotic synthesis and a high-throughput characterization in this study is expected to grow into a self-learning synthetic platform for the production of metal chalcogenide QDs for light-harvesting, light-sensing, and light-emitting applications.

Cruciform-cutting endonuclease 1 (CCE1) is an X-solvase from yeast Saccharomyces cerevisiae [Kleff, S., Kemper, B. & Sternglanz, R. (1992) EMBO J. 11, 699-704]. We report here the purification of the cloned enzyme CCE1 to near homogeneity from over-expressing Escherichia coli cells. The purified protein has a globular shape and an apparent molecular mass of 38 kDa. CCE1 reacts specifically with branched DNAs, preferably with four-armed cruciforms. The enzyme linearizes native supercoiled DNA by cutting at the base of cruciform structures as they occur in derivatives of phage M13. Supercoiling was not required for cleavage per se and a relaxed circular DNA hybrid with a stable cruciform was linearized with the same relative cleavage efficiency. Fully synthetic cruciforms (four-armed X-junctions) were also good substrates for CCE1, provided a symmetric 6-bp sequence (in our case an EcoRI restriction site) was maintained at the junction. Consequently, a synthetic cruciform made from fully randomized oligonucleotide sequences was not a substrate for CCE1. In general, cleavage sites were found clustered in a characteristic pattern in each arm of a cruciform structure. A synthetic three-armed Y-junction was also cleaved by CCE1, but with a lower efficiency than the related four-armed construct. CCE1 resolves efficiently branched synthetic DNAs in vitro. The function is consistent with the idea that CCE1 is responsible for a timely reversal of branched recombination intermediates preceding petite formation in mitochondrial DNA.

[This study takes a fresh look at the wilderness narratives Ex 15:22-17:7 and Num 11:1-20:13 from a reception theory perspective. A detailed description of the interaction between the text and a ‘co-operative reader’ is followed by a systematic depiction of how the reader is guided. Die komplexen Wustenerzahlungen Ex. 15:22-17:7 und Num. 11:1-20:13 werden in einer rezeptionsasthetisch gepragten Exegese neu untersucht. Nach einer ausfuhrlichen Beschreibung der Interaktion der Texte mit einem `kooperierenden Leser´ wird die Lenkung des Lesers in einem weiteren Hauptteil systematisch beschrieben., This study takes a fresh look at the wilderness narratives Ex 15:22-17:7 and Num 11:1-20:13 from a reception theory perspective. A detailed description of the interaction between the text and a ‘co-operative reader’ is followed by a systematic depiction of how the reader is guided. Die komplexen Wustenerzahlungen Ex. 15:22-17:7 und Num. 11:1-20:13 werden in einer rezeptionsasthetisch gepragten Exegese neu untersucht. Nach einer ausfuhrlichen Beschreibung der Interaktion der Texte mit einem `kooperierenden Leser´ wird die Lenkung des Lesers in einem weiteren Hauptteil systematisch beschrieben.]

[This study takes a fresh look at the wilderness narratives Ex 15:22-17:7 and Num 11:1-20:13 from a reception theory perspective. A detailed description of the interaction between the text and a ‘co-operative reader’ is followed by a systematic depiction of how the reader is guided. Die komplexen Wustenerzahlungen Ex. 15:22-17:7 und Num. 11:1-20:13 werden in einer rezeptionsasthetisch gepragten Exegese neu untersucht. Nach einer ausfuhrlichen Beschreibung der Interaktion der Texte mit einem `kooperierenden Leser´ wird die Lenkung des Lesers in einem weiteren Hauptteil systematisch beschrieben., This study takes a fresh look at the wilderness narratives Ex 15:22-17:7 and Num 11:1-20:13 from a reception theory perspective. A detailed description of the interaction between the text and a ‘co-operative reader’ is followed by a systematic depiction of how the reader is guided. Die komplexen Wustenerzahlungen Ex. 15:22-17:7 und Num. 11:1-20:13 werden in einer rezeptionsasthetisch gepragten Exegese neu untersucht. Nach einer ausfuhrlichen Beschreibung der Interaktion der Texte mit einem `kooperierenden Leser´ wird die Lenkung des Lesers in einem weiteren Hauptteil systematisch beschrieben.]

[This study takes a fresh look at the wilderness narratives Ex 15:22-17:7 and Num 11:1-20:13 from a reception theory perspective. A detailed description of the interaction between the text and a ‘co-operative reader’ is followed by a systematic depiction of how the reader is guided. Die komplexen Wustenerzahlungen Ex. 15:22-17:7 und Num. 11:1-20:13 werden in einer rezeptionsasthetisch gepragten Exegese neu untersucht. Nach einer ausfuhrlichen Beschreibung der Interaktion der Texte mit einem `kooperierenden Leser´ wird die Lenkung des Lesers in einem weiteren Hauptteil systematisch beschrieben., This study takes a fresh look at the wilderness narratives Ex 15:22-17:7 and Num 11:1-20:13 from a reception theory perspective. A detailed description of the interaction between the text and a ‘co-operative reader’ is followed by a systematic depiction of how the reader is guided. Die komplexen Wustenerzahlungen Ex. 15:22-17:7 und Num. 11:1-20:13 werden in einer rezeptionsasthetisch gepragten Exegese neu untersucht. Nach einer ausfuhrlichen Beschreibung der Interaktion der Texte mit einem `kooperierenden Leser´ wird die Lenkung des Lesers in einem weiteren Hauptteil systematisch beschrieben.]

The binding of Holliday structure resolving endonuclease VII to cruciform DNA was studied in the electron microscope. The protein was found to bind either to the junction or to one of the arms or an end of one of the arms of the construct. The amount of bound protein was determined by measuring the size of the complexes. On average, one complex containing three dimers was found per one molecule of cruciform DNA.