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The black phase of formamidinium lead iodide (FAPbI3) perovskite shows huge promise as an efficient photovoltaic, but it is not favoured energetically at room temperature, meaning that the undesirable yellow phases are always present alongside it during crystallization1-4. This problem has made it difficult to formulate the fast crystallization process of perovskite and develop guidelines governing the formation of black-phase FAPbI3 (refs. 5,6). Here we use in situ monitoring of the perovskite crystallization process to report an oriented nucleation mechanism that can help to avoid the presence of undesirable phases and improve the performance of photovoltaic devices in different film-processing scenarios. The resulting device has a demonstrated power-conversion efficiency of 25.4% (certified 25.0%) and the module, which has an area of 27.83 cm2, has achieved an impressive certified aperture efficiency of 21.4%.

The high toxicity, volatility, and dispersion of the light aromatics, benzene, toluene, and xylene (BTX) pose a serious threat to the environment and human health. Compared to incineration, catalytic oxidation technologies for BTX removal offer benefits such as low energy consumption, high efficiency, and low pollution. ABO3–type perovskite catalysts (ABO3–PCs) are particularly promising materials for the catalytic oxidation of BTX due to their high activity and thermal stability, as well as their adjustable elemental composition and flexible structure allowing their properties to be improved. Nonetheless, the full potential of ABO3–PCs for the oxidation of BTX has yet to be reached. This review systematically and critically analyses progress in the catalytic oxidation of BTX by ABO3–PCs. Catalytic performance is assessed for each category of perovskite, including non–doped, doped (A–, B–, or A/B–site doped), and loading type (noble metal, metal oxide, and matrix composite), with structure–activity relationships are established. A kinetic model and proposed mechanism for the catalytic oxidation of BTX are also presented. Finally, the challenges and opportunities of ABO3–PCs applied to BTX oxidation and other reactions are highlighted. [ABSTRACT FROM AUTHOR]

Exploitation of drug-drug synergism and allostery could yield superior therapies by capitalizing on the immensely diverse, but highly specific, potential associated with the biological macromolecular landscape. Here we describe a drug-drug synergy mediated by allosteric cross-talk in chromatin, whereby the binding of one drug alters the activity of the second. We found two unrelated drugs, RAPTA-T and auranofin, that yield a synergistic activity in killing cancer cells, which coincides with a substantially greater number of chromatin adducts formed by one of the compounds when adducts from the other agent are also present. We show that this occurs through an allosteric mechanism within the nucleosome, whereby defined histone adducts of one drug promote reaction of the other drug at a distant, specific histone site. This opens up possibilities for epigenetic targeting and suggests that allosteric modulation in nucleosomes may have biological relevance and potential for therapeutic interventions.

Tris(pyrazolyl)methane (tpm), 2,2,2-tris(pyrazolyl)ethanol (tpmOH) and its esterification derivatives with ibuprofen and flurbiprofen (tpmIBU and tpmFLU) were used as ligands to obtain complexes of the type [Fe(tpmX)2]Cl2 (1–4). The tpmIBU and tpmFLU ligands and corresponding complexes 3 and 4 were characterized by IR and multinuclear NMR spectroscopy, and the structure of tpmIBU was elucidated by single crystal X-ray diffraction. Complexes 1–4 were also assessed for their behaviour in aqueous media (solubility in D2O, octanol/water partition coefficient, stability in physiological-like conditions). The antiproliferative activity of ligands and complexes was determined on A2780, A2780cis and A549 cancer cell lines and the non-cancerous HEK 293T and BJ cell lines. The ligands and complexes were investigated for their ability to inhibit COX-2 (cyclooxygenase) and HNE (4-hydroxynonenal) enzymes. Complexes 3 and 4 exhibited cytotoxicity that may be attributed predominantly to their bioactive fragments, while DNA binding and enhancement of ROS production do not appear to play any significant role. [ABSTRACT FROM AUTHOR]

As a leading contender to replace lead halide perovskites, tin‐based perovskites have demonstrated ever increasing performance in solar cells and light‐emitting diodes (LEDs). They tend to be processed with dimethyl sulfoxide (DMSO) solvent, which has been identified as a major contributor to the Sn(II) oxidation during film fabrication, posing a challenge to the further improvement of Sn‐based perovskites. Herein, we use NMR spectroscopy to investigate the kinetics of the oxidation of SnI2, revealing that autoamplification takes place, accelerating the oxidation as the reaction progresses. We propose a mechanism consistent with these observations involving water participation and HI generation. Building upon these insights, we have developed low‐temperature Sn‐based perovskite LEDs (PeLEDs) processed at 60 °C, achieving enhanced external quantum efficiencies (EQEs). Our research underscores the substantial potential of low‐temperature DMSO solvent processes and DMSO‐free solvent systems for fabricating oxidation‐free Sn‐based perovskites, shaping the future direction in processing Sn‐containing perovskite materials and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Rigorous comparisons between single site-and nanoparticle (NP)-dispersed catalysts featuring the same composition, in terms of activity, selectivity, and reaction mechanism, are limited. This limitation is partly due to the tendency of single metal atoms to sinter into aggregated NPs at high loadings and elevated temperatures, driven by a decrease in metal surface free energy. Here, we have developed a unique two-step method for the synthesis of single Cu sites on ZSM-5 (termed CuS/ZSM-5) with high thermal stability. The atomic-level dispersion of single Cu sites was confirmed through scanning transmission electron microscopy, X-ray absorption fine structure (XAFS), and electron paramagnetic resonance spectroscopy. The CuS/ZSM-5 catalyst was compared to a CuO NP-based catalyst (termed CuN/ZSM-5) in the oxidation of NH3 to N2, with the former exhibiting superior activity and selectivity. Furthermore, operando XAFS and diffuse reflectance infrared Fourier transform spectroscopy studies were conducted to simultaneously assess the fate of the Cu and the surface adsorbates, providing a comprehensive understanding of the mechanism of the two catalysts. The study shows that the facile redox behavior exhibited by single Cu sites correlates with the enhanced activity observed for the CuS/ZSM-5 catalyst. [ABSTRACT FROM AUTHOR]

Hole‐transporting materials (HTMs) are indispensable for realizing efficient and stable perovskite solar cells (PSCs). Herein, a novel dibenzo[g,p]chrysene‐based HTM, termed FTPE‐OSMe, is synthesized with peripheral methoxy‐ and methylthio‐groups, which contrasts with most other small molecule HTMs that feature only methoxy‐groups. The presence of methoxy‐ and methylthio‐groups endows FTPE‐OSMe with appropriate energy levels, high‐hole mobility and enhanced interfacial interactions. PSCs employing Li‐TFSI and 4‐tert‐butylpyridine‐doped FTPE‐OSMe demonstrate a remarkable power conversion efficiency (PCE) of 24.94% (certified 24.89%). The larger‐scale PSC (1.0 cm2) and module (29.0 cm2) yield PCEs of 23.57 and 20.22%, respectively. In addition, the dopant‐free FTPE‐OSMe‐based PSCs exhibit a respectable PCE of 22.40% and excellent stability. [ABSTRACT FROM AUTHOR]

Hybrid perovskites have attracted enormous attention in the next generation resistive switching (RS) memristor for the artificial synapses, owing to their ambipolar charge transport, long diffusion length, and tunable visible bandgap. However, the variable switch, limited reproducibility, and poor endurance are the obstacles to the practical application of the perovskite memristors. Herein, we reported a multilevel RS nonvolatile memory based on a 3D trigonal HC(NH2)2PbI3 (α‐FAPbI3) perovskite layer modified by 1‐cyanobutyl‐3‐methylimidazolium chloride ([CNBmim]Cl) and sandwiched between ITO and Au electrodes (Au/[CNBmim]Cl/α‐FAPbI3/SnO2/ITO). In contrast to the bare memristor with failure switching from low resistance state (LRS) to high resistance state (HRS), the memristor device based on the α‐FAPbI3 modified with [CNBmim]Cl (Target device) shows the retention time over 104 s with On/Off ratio (>102) and endurance up to 550 cycles. The stable RS cycle benefits from the accelerated electrons de‐trapping from the reduced defects and fast charge separation in the interface of α‐FAPbI3/electrode, leading to the rupture of conductive filaments and transition of LRS to HRS. As a two‐terminal analog synaptic device, the target device can realize random handwritten digit recognition with an impressive accuracy of 89.3% on the condition of low learning phases (500 training cycles). [ABSTRACT FROM AUTHOR]