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In natural photosynthesis, the architecture of multiproteins integrates more chromophores than redox centers and simultaneously creates a well‐controlled environment around the active site. Herein, we demonstrate that these features can be emulated in a prototype hydrogen‐bonded organic framework (HOF) through simply varying the proportion of metalated porphyrin in the structure. Further studies demonstrate that changing the metalloporphyrin content not only realizes a fine tuning of the photosensitizer/catalyst ratio, but also alters the microenvironment surrounding the active site and the charge separation efficiency. As a result, the obtained material achieves the challenging overall CO2 reduction with a high HCOOH production rate (29.8 μmol g−1 h−1, scavenger free), standing out from existing competitors. This work unveils that the degree of metalation is vital to the catalytic activity of the porphryinic framework, presenting as a new strategy to optimize the performance of heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

The construction of three dimensional macroporous architectures holds exciting implications for applications such as catalysis, sensing, tissue engineering and thermal insulation. Here, we report a general self-assembly process for inorganic sponges with hierarchical porosity of intrafibre micro-/meso-/macropores and interfibre macropores. The as-fabricated SiO 2 -TiO 2 sponge possesses a high porosity of >99.86%, ultralow bulk density of 2.9 mg cm−3 and enhanced compressibility (recovery from 50% compression). The self-assembly mechanism of the SiO 2 -TiO 2 sponge has been investigated in detail. The results confirmed that the hydrolysis and polycondensation of mixed inorganic alkoxides could affect the solidification process and the charge transpote during electrospinning, and plays an essential role on the hierarchical porosity and the self-assembly of the sponge macro-structure. The concerted effects of the solidification and electrostatic repulsion between fibres are responsible for the self-assembly process of the electrospun PVP-SiO 2 -TiO 2 sponge. When used as a thermal insulation material, the SiO 2 -TiO 2 sponge shows good fireproof performances. The current contribution may guide more construction of functional inorganic macroporous architectures for advance applications in future. [ABSTRACT FROM AUTHOR]

[Display omitted] Ethanol-induced acute gastric injury is a prevalent type of digestive tract ulcer, yet conventional treatments strategies frequently encounter several limitations, such as poor bioavailability, degradation of enzymes and adverse side effects. Gallic acid (GA), a natural compound extracted from dogwood, has demonstrated potential protective effects in mitigating acute gastric injury. However, its poor stability and limited bioavailability have restricted applications in vivo. To address these issues, we report a hydrogel constructed only by gallic acid with high bioavailability for alleviation of gastric injury. Molecular dynamic simulation studies revealed that the self-assembly of GA into hydrogel was predominantly attributed to π-π and hydrogen bonds. After assembling, the GA hydrogel exhibits superior anti-oxidative stress, anti-apoptosis and anti-inflammatory properties compared with free GA. As anticipated, in vitro experiments demonstrated that GA hydrogel possessed the remarkable ability to promote the proliferation of GES-1 cells, and alleviates apoptosis and inflammation caused by ethanol. Subsequent in vivo investigation further confirmed that GA hydrogel significantly alleviated ethanol-triggered acute gastric injury. Mechanistically, GA hydrogel treatment enhanced the antioxidant capacity, reduced oxidative stress while simultaneously suppressing the secretion of pro-inflammatory cytokines and reduced the production of pro-apoptotic proteins during the process of gastric injury. Our finding suggest that this multifunctional GA hydrogel is a promising candidate for gastric injury, particularly in cases of ethanol-induced acute gastric injury. [ABSTRACT FROM AUTHOR]

Back Cover: Partial Metalation of Porphyrin Moieties in Hydrogen-Bonded Organic Frameworks Provides Enhanced CO2 Photoreduction Activity (Angew. The combination of photosensitizers and redox centers in the structure not only allows for adequate photon input and efficient utilization of the photogenerated charge, but also changes the microenvironment surrounding the active sites. Hydrogen-Bonded Organic Frameworks, Metalation, Photocatalytic CO2 Reduction, Photosensitizers, Porphyrins, Self-Assembly. [Extracted from the article]

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In natural photosynthesis, the architecture of multiproteins integrates more chromophores than redox centers and simultaneously creates a well‐controlled environment around the active site. Herein, we demonstrate that these features can be emulated in a prototype hydrogen‐bonded organic framework (HOF) through simply varying the proportion of metalated porphyrin in the structure. Further studies demonstrate that changing the metalloporphyrin content not only realizes a fine tuning of the photosensitizer/catalyst ratio, but also alters the microenvironment surrounding the active site and the charge separation efficiency. As a result, the obtained material achieves the challenging overall CO2 reduction with a high HCOOH production rate (29.8 μmol g−1 h−1, scavenger free), standing out from existing competitors. This work unveils that the degree of metalation is vital to the catalytic activity of the porphryinic framework, presenting as a new strategy to optimize the performance of heterogeneous catalysts. [ABSTRACT FROM AUTHOR]