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Efficient photocatalytic CO2 reduction coupled with the photosynthesis of pure H2O2 is a challenging and significant task. Herein, using classical CO2 photoreduction site iron porphyrinate as the linker, Ag(I) clusters were spatially separated and evenly distributed within a new metal–organic framework (MOF), namely Ag27TPyP‐Fe. With water as electron donors, Ag27TPyP‐Fe exhibited remarkable performances in artificial photosynthetic overall reaction with CO yield of 36.5 μmol g−1 h−1 and ca. 100 % selectivity, as well as H2O2 evolution rate of 35.9 μmol g−1 h−1. Since H2O2 in the liquid phase can be more readily separated from the gaseous products of CO2 photoreduction, high‐purity H2O2 with a concentration up to 0.1 mM was obtained. Confirmed by theoretical calculations and the established energy level diagram, the reductive iron(II) porphyrinates and oxidative Ag(I) clusters within an integrated framework functioned synergistically to achieve artificial photosynthesis. Furthermore, photoluminescence spectroscopy and photoelectrochemical measurements revealed that the robust connection of Ag(I) clusters and iron porphyrinate ligands facilitated efficient charge separation and rapid electron transfer, thereby enhancing the photocatalytic activity. [ABSTRACT FROM AUTHOR]

Efficient photocatalytic CO2 reduction coupled with the photosynthesis of pure H2O2 is a challenging and significant task. Herein, using classical CO2 photoreduction site iron porphyrinate as the linker, Ag(I) clusters were spatially separated and evenly distributed within a new metal–organic framework (MOF), namely Ag27TPyP‐Fe. With water as electron donors, Ag27TPyP‐Fe exhibited remarkable performances in artificial photosynthetic overall reaction with CO yield of 36.5 μmol g−1 h−1 and ca. 100 % selectivity, as well as H2O2 evolution rate of 35.9 μmol g−1 h−1. Since H2O2 in the liquid phase can be more readily separated from the gaseous products of CO2 photoreduction, high‐purity H2O2 with a concentration up to 0.1 mM was obtained. Confirmed by theoretical calculations and the established energy level diagram, the reductive iron(II) porphyrinates and oxidative Ag(I) clusters within an integrated framework functioned synergistically to achieve artificial photosynthesis. Furthermore, photoluminescence spectroscopy and photoelectrochemical measurements revealed that the robust connection of Ag(I) clusters and iron porphyrinate ligands facilitated efficient charge separation and rapid electron transfer, thereby enhancing the photocatalytic activity. [ABSTRACT FROM AUTHOR]

Molecular sieving is an ideal separation mechanism, but controlling pore size, restricting framework flexibility, and avoiding strong adsorption are all very challenging. Here, we report a flexible adsorbent showing molecular sieving at ambient temperature and high pressure, even under high humidity. While typical guest‐induced transformations are observed, a high transition pressure of 16.6 atm is observed for C2H4 at 298 K because of very weak C2H4 adsorption (~16 kJ mol−1). Also, C2H6 is completely excluded below the pore‐opening pressure of 7.7 atm, giving single‐component selectivity of ca. 300. Quantitative high‐pressure column breakthrough experiments using 1 : 1 C2H4/C2H6 mixtures at 10 atm as input confirm molecular sieving with C2H4 adsorption of 0.73 mmol g−1 or 32 cm3(STP) cm−3 and negligible C2H6 adsorption of 0.001(2) mmol g−1, and the adsorbent can be completely regenerated by inert gas purging. Furthermore, it is highly hydrophobic with negligible water adsorption, and the C2H4/C2H6 separation performance is unaffected at high humidity. [ABSTRACT FROM AUTHOR]

Supported metal catalysts with appropriate metal‐support interactions (MSIs) hold a great promise for heterogeneous catalysis. However, ensuring tight immobilization of metal clusters/nanoparticles on the support while maximizing the exposure of surface active sites remains a huge challenge. Herein, we report an Ir/WO3 catalyst with a new enrooted‐type MSI in which Ir clusters are, unprecedentedly, atomically enrooted into the WO3 lattice. The enrooted Ir atoms decrease the electron density of the constructed interface compared to the adhered (root‐free) type, thereby achieving appropriate adsorption toward oxygen intermediates, ultimately leading to high activity and stability for oxygen evolution in acidic media. Importantly, this work provides a new enrooted‐type supported metal catalyst, which endows suitable MSI and maximizes the exposure of surface active sites in contrast to the conventional adhered, embedded, and encapsulated types. [ABSTRACT FROM AUTHOR]

Considering that CO2 reduction is mostly a multielectron reaction, it is necessary for the photocatalysts to integrate multiple catalytic sites and cooperate synergistically to achieve efficient photocatalytic CO2 reduction to various products, such as C2 hydrocarbons. Herein, through crystal engineering, we designed and constructed a metal–organic framework‐derived Zr/Ti bimetallic oxide solid solution support, which was confirmed by X‐ray diffraction, electron microscopy and X‐ray absorption spectroscopy. After anchoring Au nanoparticles, the composite photocatalyst exhibited excellent performances toward photocatalytic CO2 reduction to syngas (H2 and CO production rates of 271.6 and 260.6 μmol g−1 h−1) and even C2 hydrocarbons (C2H4 and C2H6 production rates of 6.80 and 4.05 μmol g−1 h−1). According to the control experiments and theoretical calculations, the strong interaction between bimetallic oxide solid solution support and Au nanoparticles was found to be beneficial for binding intermediates and reducing CO2 reduction, highlighting the synergy effect of the catalytic system with multiple active sites. [ABSTRACT FROM AUTHOR]

Neuropathic pain (NeP) is a major health concern. Due to the complex pathological mechanisms, management of NeP is challenging. Emodin, a natural anthraquinone derivative, exerts excellent analgesic effects. However, its mechanisms of action are still poorly understood. In this study, we investigated the mechanisms underlying pain‐relief effects of emodin in the cerebral cortex using proteomic and metabolomic approaches. After 15 days of emodin administration, the mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) values in the emodin groups were significantly higher than those in the chronic constriction injury (CCI) group (p <.05), suggesting emodin treatment could reverse CCI‐induced hyperalgesia. Emodin treatment evoked the expression alteration of 402 proteins (153 up‐regulated and 249 down‐regulated) in the CCI models, which were primarily involved in PI3K/AKT signaling pathway, gamma‐aminobutyric acid (GABA) receptor signaling, complement and coagulation cascades, cGMP/PKG signaling pathway, MAPK signaling pathway, and calcium signaling pathway. In parallel, emodin intervention regulated the abundance alteration of 27 brain metabolites (20 up‐regulated and 7 down‐regulated) in the CCI rats, which were primarily implicated in carbon metabolism, biosynthesis of amino acids, pentose phosphate pathway, and glucagon signaling pathway. After a comprehensive analysis and western blot validation, we demonstrated that emodin alleviated NeP mainly through regulating GABAergic pathway and PI3K/AKT/NF‐κB pathway. [ABSTRACT FROM AUTHOR]

Heterogeneous Catalysis. Metal‐support interactions between embedded Ir clusters and their WO3 support boost the oxygen evolution reaction in acidic media, as reported by Xin Xiao, Lei Li, Meng Danny Gu, Qiang Xu in their Research Article (e202406947)...By Wenjuan Wang; Cheng Li; Chuan Zhou; Xin Xiao; Fayan Li; Ning‐Yu Huang; Lei Li; Meng Gu and Qiang XuReported by Author; Author; Author; Author; Author; Author; Author; Author; Author [Extracted from the article]

In a recent article published in Angewandte Chemie, researchers Lei Li, Qiang Xu, and their team discuss their findings on achieving efficient photocatalytic CO2 reduction. The researchers utilized crystal engineering and derivation techniques to create a metal-organic framework-derived Zr/Ti bimetallic oxide solid solution anchored with Au nanoparticles. This innovative approach resulted in the successful reduction of CO2 to syngas and C2 hydrocarbons under simulated solar light irradiation. The study highlights the importance of integrating multiple catalytic sites and cooperation between them for effective CO2 reduction. [Extracted from the article]

A Journal of the German Chemical Society AngewandteChemie www. angewandte. org International Edition 2024– 63/ 21 I. ntegrating multiple catalytic sites … … and cooperating synergistically are the keys to achieve efficient photocatalytic CO2 reduction. In their Research Article ( e202319177), Lei Li, Qiang Xu et al. report a metal- organic framework- derived Zr/ Ti bimetallic oxide solid solution anchored with Au nanoparticles through crystal engineering and derivation, achieving photocatalytic CO2 reduction to syngas and eventually C2 hydrocarbons under simulated solar light irradiation. [Extracted from the article]

Porous molecular crystals sustained by hydrogen bonds and/or weaker connections are an intriguing type of adsorbents, but they rarely demonstrate efficient adsorptive separation because of poor structural robustness and tailorability. Herein, we report a porous molecular crystal based on hydrogen‐bonded cyclic dinuclear AgI complex, which exhibits exceptional hydrophobicity with a water contact angle of 134°, and high chemical stability in water at pH 2–13. The seemingly rigid adsorbent shows a pore‐opening or nonporous‐to‐porous type butane adsorption isotherm and complete exclusion of isobutane, indicating potential molecular sieving. Quantitative column breakthrough experiments show slight co‐adsorption of isobutane with an experimental butane/isobutane selectivity of 23, and isobutane can be purified more efficiently than for butane. In situ powder/single‐crystal X‐ray diffraction and computational simulations reveal that a trivial guest‐induced structural transformation plays a critical role. [ABSTRACT FROM AUTHOR]

Efficient adsorptive separation of propylene/propane (C3H6/C3H8) is highly desired and challenging. Known strategies focus on either the thermodynamic or the kinetic mechanism. Here, we report an interesting reactivity of a metal–organic framework that improves thermodynamic and kinetic adsorption selectivity simultaneously. When the metal–organic framework is heated under oxygen flow, half of the soft methylene bridges of the organic ligands are selectively oxidized to form the more polar and rigid carbonyl bridges. Mixture breakthrough experiments showed drastic increase of C3H6/C3H8 selectivity from 1.5 to 15. For comparison, the C3H6/C3H8 selectivities of the best‐performing metal–organic frameworks Co‐MOF‐74 and KAUST‐7 were experimentally determined to be 6.5 and 12, respectively. Gas adsorption isotherms/kinetics, single‐crystal X‐ray diffraction, and computational simulations revealed that the oxidation gives additional guest recognition sites, which improve thermodynamic selectivity, and reduces the framework flexibility, which generate kinetic selectivity. [ABSTRACT FROM AUTHOR]

Efficient photocatalytic CO2 reduction coupled with the photosynthesis of pure H2O2 is a challenging and significant task. Herein, using classical CO2 photoreduction site iron porphyrinate as the linker, Ag(I) clusters were spatially separated and evenly distributed within a new metal–organic framework (MOF), namely Ag27TPyP‐Fe. With water as electron donors, Ag27TPyP‐Fe exhibited remarkable performances in artificial photosynthetic overall reaction with CO yield of 36.5 μmol g−1 h−1 and ca. 100 % selectivity, as well as H2O2 evolution rate of 35.9 μmol g−1 h−1. Since H2O2 in the liquid phase can be more readily separated from the gaseous products of CO2 photoreduction, high‐purity H2O2 with a concentration up to 0.1 mM was obtained. Confirmed by theoretical calculations and the established energy level diagram, the reductive iron(II) porphyrinates and oxidative Ag(I) clusters within an integrated framework functioned synergistically to achieve artificial photosynthesis. Furthermore, photoluminescence spectroscopy and photoelectrochemical measurements revealed that the robust connection of Ag(I) clusters and iron porphyrinate ligands facilitated efficient charge separation and rapid electron transfer, thereby enhancing the photocatalytic activity. [ABSTRACT FROM AUTHOR]

Efficient photocatalytic CO2 reduction coupled with the photosynthesis of pure H2O2 is a challenging and significant task. Herein, using classical CO2 photoreduction site iron porphyrinate as the linker, Ag(I) clusters were spatially separated and evenly distributed within a new metal–organic framework (MOF), namely Ag27TPyP‐Fe. With water as electron donors, Ag27TPyP‐Fe exhibited remarkable performances in artificial photosynthetic overall reaction with CO yield of 36.5 μmol g−1 h−1 and ca. 100 % selectivity, as well as H2O2 evolution rate of 35.9 μmol g−1 h−1. Since H2O2 in the liquid phase can be more readily separated from the gaseous products of CO2 photoreduction, high‐purity H2O2 with a concentration up to 0.1 mM was obtained. Confirmed by theoretical calculations and the established energy level diagram, the reductive iron(II) porphyrinates and oxidative Ag(I) clusters within an integrated framework functioned synergistically to achieve artificial photosynthesis. Furthermore, photoluminescence spectroscopy and photoelectrochemical measurements revealed that the robust connection of Ag(I) clusters and iron porphyrinate ligands facilitated efficient charge separation and rapid electron transfer, thereby enhancing the photocatalytic activity. [ABSTRACT FROM AUTHOR]