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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]

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]

Photocatalytic organic reactions, harvesting solar energy to produce high value-added organic chemicals, have attracted increasing attention as a sustainable approach to address the global energy crisis and environmental issues. Reticular framework materials, including metal–organic frameworks (MOFs) and covalent organic frameworks (COFs), are widely considered as promising candidates for photocatalysis owing to their high crystallinity, tailorable pore environment and extensive structural diversity. Although the design and synthesis of MOFs and COFs have been intensively developed in the last 20 years, their applications in photocatalytic organic transformations are still in the preliminary stage, making their systematic summary necessary. Thus, this review aims to provide a comprehensive understanding and useful guidelines for the exploration of suitable MOF and COF photocatalysts towards appropriate photocatalytic organic reactions. The commonly used reactions are categorized to facilitate the identification of suitable reaction types. From a practical viewpoint, the fundamentals of experimental design, including active species, performance evaluation and external reaction conditions, are discussed in detail for easy experimentation. Furthermore, the latest advances in photocatalytic organic reactions of MOFs and COFs, including their composites, are comprehensively summarized according to the actual active sites, together with the discussion of their structure–property relationship. We believe that this study will be helpful for researchers to design novel reticular framework photocatalysts for various organic synthetic applications. [ABSTRACT FROM AUTHOR]

Two-dimensional metal-organic frameworks (2D MOFs), as a new type of 2D materials, have been widely applied in various applications because of their unique structures and exposed active sites. Herein, we reported two low-cost 2D MOFs constructed by a raw chemical succinic acid (SA), M-SA (M = Ni or Co), which served as efficient photocatalysts for the reduction of CO2 to CO. Taking advantage of the thinness and open metal sites, the ultrathin Ni-SA nanosheets (ca. 3.6 nm) exhibited excellent CO production of 6.96(7) mmol·g−1h−1 and CO selectivity of 96.6%. Photoelectrochemical tests and theoretical calculations further confirmed the higher charge transfer efficiency and unsaturated metal sites for promoting photocatalytic performances. More importantly, Ni-SA can also be synthesized in large-scale by an energy-saving method under room temperature, strongly suggesting its promising future and potential for practical applications. [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]

Here, we report an improved tandem catalytic mechanism for electroreduction of CO2 to C2H4. Cu(111) nanoparticles with an average size of 5.5 ± 0.9 nm were anchored on a conductive Cu-based metal–organic framework (Cu-THQ) by in situ electrochemical synthesis. Compared to Cu(111) nanoparticles, the C2H4 faradaic efficiency of the tandem catalyst Cu(111)@Cu-THQ was increased doubly. [ABSTRACT FROM AUTHOR]

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]

The methylene groups surrounding the metal center in a metal–organic framework provide hydrophobic repulsive forces to H2O, resulting in a high catalytic activity (TOF = 73.8 h−1, selectivity of 96%) for photodriven CO2 reduction into CO. [ABSTRACT FROM AUTHOR]

Porous materials bearing free aliphatic amine groups are powerful adsorbents for carbon dioxide but generally have to be synthesized by complicated, multi-step post-synthetic modification methods due to the high activity of these functional groups. We report a crystal-engineering strategy for such metal–organic frameworks. Reactions of Zn(ii) ion with diversified coordination modes and bis(4-carboxy-benzyl)amine (H2bcba) with a secondary aliphatic amine bridge at different temperatures yielded a pair of isomeric frameworks with very similar framework structures but distinctly different local structures, namely α-[Zn(bcba)] (MCF-51 or α-Zn) with all amino groups coordinated and β-[Zn(bcba)] (MCF-52 or β-Zn) with uncoordinated amino groups. Single-component gas adsorption and CO2/CH4 mixture breakthrough experiments at ambient conditions showed that, the CO2 adsorption ability and CH4 purification performances of β-Zn, in terms of CO2 adsorption enthalpy (42 kJ mol−1), CO2/CH4 selectivity (32) and CH4 purity/productivity (1.49 mmol g−1 at 99.999%+), are much higher than those of α-Zn (CO2 adsorption enthalpy of 17 kJ mol−1, CO2/CH4 selectivity of 2.9 and CH4 purity/productivity of 0.088 mmol g−1 at 99%+). [ABSTRACT FROM AUTHOR]

Converting CO2 into fuels via photochemical reactions relies on highly efficient and selective catalysts. We demonstrate that the catalytic active metal center can cooperate with neighboring hydroxide ligands to boost the photocatalytic CO2 reduction. Six cobalt-based metal-organic frameworks (MOFs) with different coordination environments are studied at the same reaction condition (photosensitizer, electron donor, water/organic mixed solvent, and visible light). In pure CO2 at 1.0 atm, the MOFs bearing μ-OH- ligands neighboring the open Co centers showed CO selectivities and turnover frequencies (TOFs) up to 98.2% and 0.059 s-1, respectively. More importantly, their TOFs reduced only ca. 20% when the CO2 partial pressure was reduced to 0.1 atm, while other MOFs reduced by at least 90%. Periodic density functional theory calculations and isotope tracing experiments showed that the μ-OH-ligands serve not only as strong hydrogen-bonding donors to stabilize the initial Co-CO2 adduct but also local proton sources to facilitate the C-O bond breaking. [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]