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Subnanometric metal species (single atoms and clusters) have been demonstrated to be unique compared with their nanoparticulate counterparts. However, the poor stabilization of subnanometric metal species towards sintering at high temperature (>500 °C) under oxidative or reductive reaction conditions limits their catalytic application. Zeolites can serve as an ideal support to stabilize subnanometric metal catalysts, but it is challenging to localize subnanometric metal species on specific sites and modulate their reactivity. We have achieved a very high preference for localization of highly stable subnanometric Pt and PtSn clusters in the sinusoidal channels of purely siliceous MFI zeolite, as revealed by atomically resolved electron microscopy combining high-angle annular dark-field and integrated differential phase contrast imaging techniques. These catalysts show very high stability, selectivity and activity for the industrially important dehydrogenation of propane to form propylene. This stabilization strategy could be extended to other crystalline porous materials.

Modulating the structures of subnanometric metal clusters at the atomic level is a great synthetic and characterization challenge in catalysis. Here, we show how the catalytic properties of subnanometric platinum clusters (0.5–0.6 nm) confined in the sinusoidal 10R channels of purely siliceous MFI zeolite are modulated upon introduction of partially reduced tin species that interact with the noble metal at the metal/support interface. The platinum–tin clusters are stable in H 2 over an extended period of time (>6 h), even at high temperatures (for example, 600 °C), which is determined by only a few additional tin atoms added to the platinum clusters. The structural features of platinum–tin clusters, which are not immediately visible by conventional characterization techniques but can be established after combination of in situ extended X-ray absorption fine structure, high-angle annular dark-field scanning transmission electron microscopy and CO infrared data, are key to providing a one-order of magnitude lower deactivation rate in the propane dehydrogenation reaction while maintaining high intrinsic (initial) catalytic activity. Tuning the structures of subnanometric metal clusters is challenging but can unlock unexpected catalytic properties. Here, the authors show that changing the composition of MFI zeolite-encapsulated PtSn subnanometric clusters by adding just a few tin atoms can lead to a remarkable stability enhancement in propane dehydrogenation.

Zeolites containing Rh single sites stabilized by phosphorous were prepared through a one-pot synthesis method and are shown to have superior activity and selectivity for ethylene hydroformylation at low temperature (50 °C). Catalytic activity is ascribed to confined Rh 2 O 3 clusters in the zeolite which evolve under reaction conditions into single Rh 3+ sites. These Rh 3+ sites are effectively stabilized in a Rh-(O)-P structure by using tetraethylphosphonium hydroxide as a template, which generates in situ phosphate species after H 2 activation. In contrast to Rh 2 O 3 , confined Rh 0 clusters appear less active in propanal production and ultimately transform into Rh(I)(CO) 2 under similar reaction conditions. As a result, we show that it is possible to reduce the temperature of ethylene hydroformylation with a solid catalyst down to 50 °C, with good activity and high selectivity, by controlling the electronic and morphological properties of Rh species and the reaction conditions. Isolated Rh 3+ sites are stabilized inside the MFI zeolite channels with phosphorous which is added during zeolite synthesis in the form of a phosphonium zeolite template. This Rh 3+ shows high activity in the low-temperature ethylene hydroformylation.

The rational design of robust nanocatalysts containing the suitable active sites for building relevant organic compounds, such as lactams, is a desired approximation towards the development of a sustainable fine chemistry field. In that sense, the design of a proper nanomaterial able to mediate the selective hydrodeoxygenation of cyclic imides to lactams with high tolerance to the preservation of aromatic rings remains rather unexplored. Here, we show the design of a bimetallic AgRe nanomaterial with notable activity and selectivity to mediate this transformation affording more than 60 lactams from the corresponding imides. Interestingly, in this work we disclose that the optimal AgRe nanocatalyst is constituted by AgReO 4 nanoaggregates that undergo an in situ hydrogenative dispersion to form the active centers composed by Ag 0 nanoparticles and ReO x species. Deep characterization, together with kinetic and mechanistic studies, have revealed that the intimate Ag-Re contact intrinsic to AgReO 4 species is key for the formation of the most active catalytic sites and the proper bimetallic cooperation required for mediating the desired process. Sustainable synthesis of valuable organic compounds like lactams relies on efficient catalysts. Here, the authors report a bimetallic silver–rhenium catalyst that selectively converts cyclic imides to lactams with high efficiency, with close silver–rhenium contact being key to its performance.

Mercury (Hg) pollution in agricultural soils and its potential pathway to the human food chain can pose a serious health concern. Understanding the pathway of Hg in plants and how the speciation may change upon interaction with other elements used for biofortification can be critical to assess the real implications for the final plant-based product. In that respect, selenium (Se) biofortification of crops grown in Se-poor soil regions is becoming a common practice to overcome Se deficient diets. Therefore, it is important to assess the interplay between these two elements since Se may form complexes with Hg reducing its bioavailability and toxicity. In this work, the speciation of Hg in wheat plants grown hydroponically under the presence of Hg (HgCl 2 ) and biofortified with Se (selenite, selenate, or a 1:1 mixture of both) has been investigated by X-ray absorption spectroscopy at the Hg L 3 -edge. The main Hg species found in wheat grains was the highly toxic methylmercury. It was found that the Se-biofortification of wheat did not prevent, in general, the Hg translocation to grains. Only the 1:1 mixture treatment seemed to have an effect in reducing the levels of Hg and the presence of methylmercury in grains.

We report on the microscopic structure of water at sub- and supercritical conditions studied using X-ray Raman spectroscopy, ab initio molecular dynamics simulations, and density functional theory. Systematic changes in the X-ray Raman spectra with increasing pressure and temperature are observed. Throughout the studied thermodynamic range, the experimental spectra can be interpreted with a structural model obtained from the molecular dynamics simulations. A spatial statistical analysis using Ripley’s K-function shows that this model is homogeneous on the nanometer length scale. According to the simulations, distortions of the hydrogen-bond network increase dramatically when temperature and pressure increase to the supercritical regime. In particular, the average number of hydrogen bonds per molecule decreases to ≈0.6 at 600 °C and p = 134 MPa.

N‐donor ligands such as n‐Pr‐BTP [2,6‐bis(5,6‐dipropyl‐1,2,4‐triazin‐3‐yl)pyridine] preferentially bind trivalent actinides (An3+) over trivalent lanthanides (Ln3+) in liquid–liquid separation. However, the chemical and physical processes responsible for this selectivity are not yet well understood. Here, an explorative comparative X‐ray spectroscopy and computational (L3‐edge) study for the An/Ln L3‐edge and the N K‐edge of [An/Ln(n‐Pr‐BTP)3](NO3)3, [Ln(n‐Pr‐BTP)3](CF3SO3)3 and [Ln(n‐Pr‐BTP)3](ClO4)3 complexes is presented. High‐resolution X‐ray absorption near‐edge structure (HR‐XANES) L3‐edge data reveal additional features in the pre‐ and post‐edge range of the spectra that are investigated using the quantum chemical codes FEFF and FDMNES. X‐ray Raman spectroscopy studies demonstrate the applicability of this novel technique for investigations of liquid samples of partitioning systems at the N K‐edge. Exploring the opportunities and challenges when studying actinide and lanthanide N‐donor ligand systems relevant for separation technologies from the metal and ligand point of view using X‐ray spectroscopy techniques and computations.

The use of lithium–sulfur batteries under high sulfur loading and low electrolyte concentrations is severely restricted by the detrimental shuttling behavior of polysulfides and the sluggish kinetics in redox processes. Two‐dimensional (2D) few layered black phosphorus with fully exposed atoms and high sulfur affinity can be potential lithium–sulfur battery electrocatalysts, which, however, have limitations of restricted catalytic activity and poor electrochemical/chemical stability. To resolve these issues, we developed a multifunctional metal‐free catalyst by covalently bonding few layered black phosphorus nanosheets with nitrogen‐doped carbon‐coated multiwalled carbon nanotubes (denoted c‐FBP‐NC). The experimental characterizations and theoretical calculations show that the formed polarized P–N covalent bonds in c‐FBP‐NC can efficiently regulate electron transfer from NC to FBP and significantly promote the capture and catalysis of lithium polysulfides, thus alleviating the shuttle effect. Meanwhile, the robust 1D‐2D interwoven structure with large surface area and high porosity allows strong physical confinement and fast mass transfer. Impressively, with c‐FBP‐NC as the sulfur host, the battery shows a high areal capacity of 7.69 mAh cm−2 under high sulfur loading of 8.74 mg cm−2 and a low electrolyte/sulfur ratio of 5.7 μL mg−1. Moreover, the assembled pouch cell with sulfur loading of 4 mg cm−2 and an electrolyte/sulfur ratio of 3.5 μL mg−1 shows good rate capability and outstanding cyclability. This work proposes an interfacial and electronic structure engineering strategy for fast and durable sulfur electrochemistry, demonstrating great potential in lithium–sulfur batteries. A two‐dimensional phosphorene‐based metal‐free catalytic sulfur cathode was developed by covalently bonding phosphorene with N‐doped carbon‐coated multiwalled carbon nanotubes. The porous interwoven structure and electronic engineering facilitate fast ion transfer and strengthen the adsorption for polysulfides, resulting in superior sulfur confinement and promoting polysulfide conversion significantly.

Selenium (Se) is an essential micronutrient, yet its deficiency remains a global concern. This study investigates the biofortification of alfalfa (Medicago sativa cv. ProINTA Super Monarca GR9) via foliar Se application to enhance Se accumulation and transformation into bioavailable organic forms. A controlled environment experiment in a plant growth chamber and a one-season open-field trial (January 2023, Argentina) were conducted. Treatments included sodium selenate (Se(VI)), sodium selenite (Se(IV)), and a 1:1 mixture, applied at 45 and 90 g Se ha−1, with and without the biostimulant BIOFORGE®. Treated plants exhibited increased Se content, correlating with the applied doses. X-ray absorption spectroscopy (XAS) confirmed that most inorganic Se was transformed into organic Se forms, with Se(IV) treatments yielding the highest concentrations of organic Se species such as selenocysteine (SeCys) and selenomethionine (SeMet). Open-field trials showed a complete conversion of Se, though total Se accumulation was lower than in controlled conditions. Se treatments did not affect forage quality or biomass production. The biostimulant slightly reduced Se uptake but did not compromise biofortification. These results highlight Se(IV) as the optimal treatment for alfalfa biofortification, presenting a sustainable strategy to enhance dietary Se intake through functional foods.

Background Continuing symptoms and poor health following cancer treatments may alter meaning in life for cancer survivors. Gynecologic cancer survivors are particularly troubled with physical sequelae. In addition, for the most common sites of disease, such as breast and gynecologic cancers, the prevalence of depression is also high. Purpose This study tests meaning in life as a mechanism for the relationship between physical symptoms and depressive symptoms. Methods Gynecologic cancer survivors ( N  = 260) participated. Measures of physical sequelae (nurse rated symptoms/signs, patient-reported gynecologic symptoms), meaning in life (harmony, life purpose, spirituality, and conversely, confusion and loss), and depressive symptoms were obtained at the time of a routine clinical follow-up visit 2–10 years following the completion of treatment. Latent variables were defined, and structural equation modeling tested a mediator model. Results Analyses support partial mediation. That is, survivors with more physical sequelae also reported lower levels of meaning in life, which was associated with higher levels of depressive symptoms. Conclusions Gynecologic cancer patients have been neglected in psychosocial research, and findings highlight the importance of existential issues in their lives. While many adjust well, those with persistent physical functioning deficits may experience depressive symptoms. By appreciating the role of meaning in their experience, we may help survivors foster their own growth and perspectives important for their future.