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Using solar energy through green and simple artificial photosynthesis systems are considered as a promising way to solve the energy and environmental crisis. However, one of the important primary steps of photosynthesis, i.e., energy transfer, is long being ignored especially in inorganic semiconducting systems due to the small exciton binding energies. Herein, the simultaneous interrogation of the charge transfer and energy transfer steps in a photoexcitation process is proposed by utilizing few‐layered nanosheet‐assembled hierarchical BiOBr nanotubes with rich oxygen vacancies (OVs) as efficient multifunctional photocatalysts. Benefiting from the integrated 1D/2D structure and abundant OV defects, the excitonic effect strikes a delicate balance in the optimized BiOBr photocatalyst, showing not only improved charge carrier separation and transfer but also enhanced exciton generation. As a result, the hierarchical BiOBr nanotubes exhibit high efficiency toward photocatalytic CO2 reduction with an impressive CO evolution rate of 135.6 µmol g−1 h−1 without cocatalyst or photosensitizer. The dominant reactive oxygen species of singlet oxygen (1O2) are discriminated for the first time, which originated from an energy transfer process, with electrophilic character, whereas the minor effect of superoxide anion radical (•O2−) with a nucleophilic rate‐determining step in the photocatalytic aerobic oxidation of sulfides. [ABSTRACT FROM AUTHOR]

Non‐noble metal‐based bifunctional electrocatalysts are highly desired for water electrolysis. However, constructing a water electrolyzer using a sole catalyst without compromising either its oxygen evolution reaction (OER) or hydrogen evolution reaction (HER) performance is still challenging. In this study, a simple strategy is developed to integrate 2 D and 0 D CoP in the same metal–organic framework precursor‐derived hollow N‐doped carbon nanotube‐assembled polyhedron (HNCNP). The unique hierarchical structure endows the resulting nanocomposite with both the advantages of more exposed active sites for 2 D and large surface‐to‐volume ratio for 0 D materials, whereas the hollow interior could benefit the charge and mass transfer properties. Thus, CoP/HNCNP@2 D CoP exhibits outstanding OER and HER activity and a low cell voltage when employed as both the anode and cathode in a two‐electrode water electrolyzer. The approach of integrating the same metal phosphide phase with diverse dimensions may inspire new ways to design hierarchical nanostructures for advanced energy conversion applications. [ABSTRACT FROM AUTHOR]

The effective deposition of metal–organic frameworks on kinds of biomaterials is still challenging and highly desirable. Using polydopamine as the effective nucleation center, HKUST‐1 is successfully prepared on three kinds of inert biomaterials, i.e., titanium oxide film (Ti–O), 316L stainless steel (316L SS), and poly(vinyl chloride) (PVC). Characterization of the surfaces by powder X‐ray diffraction confirm the oriented crystal growth of HKUST‐1 on the polydopamine coated substrates. There are no significant difference in catalytical NO generation and surface copper content of the three samples with HKUST‐1 deposition. All keep a NO release speed of ≈2.5 × 10−10 mol cm−2 min−1, thus platelet activation on the HKUST‐1 modified surfaces are inhibited compared to that of the unmodified ones. Ex vivo test shows thrombi formation is dramatically reduced. The HKUST‐1 coated surfaces elicit 95% reduction in the bacterial attachment of both Staphylococcus aureus and Escherichia coli. The endothelial cells and macrophages culture results support good biocompatibility of the modified surfaces. It provides a promising, facile, and effective approach for surface modification of blood contact biomaterials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Yolk-shelled Co-CeO 2 -H 2 octahedrons with rich vacancy defects are prepared by sequential calcinating the Co-incorporated Ce-UiO-66 precursor. • Defect engineering on the catalyst surface promotes efficient carrier separation and transfer and reduces the energy barrier for CO 2 activation and transformation. • Co-incorporation with CeO 2 is responsible for extended light absorption. • 1%–Co-CeO 2 -H 2 exhibits significantly enhanced photocatalytic CO 2 reduction activity. Solar-driven photocatalytic CO 2 conversion is considered as the most promising approach to eliminating atmospheric CO 2 emissions. However, great challenges lie in the utilization of visible-infrared light and the activation of the inert CO 2 molecule. Herein, we report the preparation of a yolk-shell Co-CeO 2 octahedron and the strategy for surface defect engineering to optimize the photocatalyst by two-step calcination of a Ce-based metal–organic framework (Ce-UiO-66). As a result of the synergistic effect of incorporating the Co atom and rich oxygen vacancies, the energy barrier of activating and transforming the adsorbed CO 2 to *COOH is significantly reduced. Benefiting from the structure with high surface area, cavity, and abundant defects, the optimized Co-CeO 2 photocatalyst not only provides more exposed active sites and enhanced photoabsorption but also improves charge separation and transfer. Accordingly, 1%–Co-CeO 2 -H 2 exhibits much higher photocatalytic activity in CO 2 reduction under visible light irradiation with a CO generation rate of 46.9 μmol/h, which is 4.6 times than that of less defective 1%–Co-CeO 2 , and far more than that of pure CeO 2. [ABSTRACT FROM AUTHOR]

A biomimetic di-μ-oxo dimanganese complex bearing two triazole-binding tridentate ligands is successfully anchored inside a metal–organic framework (MOF) through a covalent-functionalization-assisted coordination strategy, exhibiting high activity and reliable durability in the chemical water oxidation reaction. [ABSTRACT FROM AUTHOR]

Given the shortage of sustainable resources and the increasingly serious environmental issues in recent decades, the demand for clean technologies and sustainable feedstocks is of great interest to researchers worldwide. With regard to the fields of energy saving and environmental remediation, the key point is the development of efficient catalysts, not only in terms of facile synthesis methods, but also the benign utilization of such catalysts. This work reviews the use of metal-organic frameworks (MOFs) and MOF-based materials in these fields. The definition of MOFs and MOF-based materials will be primarily introduced followed by a brief description of the characterization and stability of MOF-related materials under the applied conditions. The greening of MOF synthesis processes will then be discussed and catalogued by benign solvents and conditions and green precursors of MOFs. Furthermore, their suitable application in sustainable catalysis will be summarized, focusing on several typical atom-economic reactions, such as the direct introduction of H2 or O2 and C−C bond formation. Approaches towards reducing CO2 emission by MOF-based catalysts will be described with special emphasis on CO2 fixation and CO2 reduction. In addition, driven by the explosive growth of energy consumption in the last century, much research has gone into biomass, which represents a renewable alternative to fossil fuels and a sustainable carbon feedstock for chemical production. The advanced progress of biomass-related transformations is also illustrated herein. Fundamental insights into the nature of MOF-based materials as constitutionally easily recoverable heterogeneous catalysts and as supports for various active sites is thoroughly discussed. Finally, challenges facing the development of this field and the outlook for future research are presented. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs), which are known as a class of porous coordination polymers, have proven to be of great significance to manifold applications, owing to their fascinating topology, ultrahigh porosity, enormous internal surface area, and the combination of being as rigid as inorganic materials and as flexible as organic materials . In this review, we give a concise history of the development of MOFs as functional materials prior to our entry into this area in 2006, then a summary of our road to participate in and extend the outline of the research in MOFs chemistry, as well as the challenge in further designing applicable functional materials. We describe not only the road of evolution from the past, present, and future of this chemistry, but also the road to finalize a functional material from the desire to the design, synthesis, and postmodification of a MOF. Throughout the review, we particularly emphasize the improvements in the application of MOFs as heterogeneous catalysts, such as employing MOFs as one component for the construction of composites, and their extended scope in tough catalytic reactions. Examples of applications in gas storage and separation, small molecular sensing, and our perspectives for future applications triggered by MOFs, are also introduced. [ABSTRACT FROM AUTHOR]

Healing of chronic wounds has been critically limited by prolonged inflammation. Carbon monoxide (CO) is a biologically active molecule with high potential based on its efficacy in modulating inflammation, promoting wound healing and tissue remodeling. Strategies to use CO as a gaseous drug to chronic wounds have emerged, but controlling the sustained release of CO at the wound site remains a major challenge. In this work, a porphyrin-Fe based metal organic frameworks, TPyP-FeMOFs was prepared. The synthesized TPyP-FeMOFs was high-temperature vacuum activated (AcTPyP-FeMOFs) and AcTPyP-FeMOFs had a relatively high Fe (II) content. CO sorption isotherms showed that AcTPyP-FeMOFs chemisorbed CO and thus CO release was sustained and prolonged. In vitro evaluation results showed that CO@TPyP-FeMOFs reduced the inflammatory level of lipopolysaccharide (LPS) activated macrophages, polarized macrophages to M2 anti-inflammatory phenotype, and promoted the proliferation of fibroblasts by altering the pathological microenvironment. In vivo study confirmed CO@TPyP-FeMOFs promoted healing in a LPS model of delayed cutaneous wound repair and reduced macrophages and neutrophils recruitment. Both in vitro and in vivo studies verified that CO@TPyP-FeMOFs acted on macrophages by modulating phenotype and inflammatory factor expression. Thus, CO release targeting macrophages and pathological microenvironment modulation presented a promising strategy for wound healing. [Display omitted] • A new CO donor CO@TPyP-FeMOFs was developed and used for macrophage phenotypic polarization regulating. • It reduced the inflammatory level of lipopolysaccharide (LPS) activated macrophages, polarized macrophages to M2 anti-inflammatory phenotype. • Paracrine microenvironment altering by polarizing macrophage from M1 to M2 is beneficial for fibroblast growth and proliferation. • It promoted healing in a LPS model of delayed cutaneous wound repair. [ABSTRACT FROM AUTHOR]

Review: [59 refs. [ABSTRACT FROM AUTHOR]

To explore efficient non-noble metal-based electrocatalysts for oxygen reduction reaction (ORR), herein we developed a facile bottom-up approach for the fabrication of a hollow porous carbon sphere codoped with ultra-small Co nanoparticles and uniform nitrogen distribution (Co-HNCS) via one-step pyrolysis of a core-shell type precursor composing of polystyrene (PS) core and bimetallic ZIF (zeolite imidazolate framework) shell. The bimetallic Co-Zn-ZIFs (BMZIFs) was selected as the sacrifice template due to not only its high nitrogen content and regular porosity but also the superiority that Zn species in BMZIFs can both spatially separate Co species to suppress the aggregation of ultra-small Co NPs and be evaporated to afford extra pores during high-temperature pyrolysis. As expected, by adjusting the starting molar ratio of Zn to Co, we were able to prepare Co-HNCS- x ( x represent the molar ratio of Co to total starting metal feeding) that exhibited unique hollow structure with large surface areas, enhanced mass transport, high porosities, tunable particle sizes and graphitization degrees, abundant highly active CoN x sites, and thus significantly improved ORR performance. Particularly, the optimal Co-HNCS-0.2 exhibited the remarkable ORR activity (the onset and half-wave potentials were 0.94 and 0.82 V vs. RHE, respectively) via an efficient four-electron-dominant ORR process in alkaline medium, which outperformed that of commercial Pt/C (20 wt%, the onset and half-wave potentials were 0.93 and 0.80 V vs. RHE, respectively) and most of previously reported Co-based catalysts. Moreover, it also displayed much superior stability and tolerance to methanol as compared to Pt/C, further highlighting the merit of this facile synthesis approach. Our findings might inspire new thoughts on the development of precious-metal-free, highly-efficient and cost-effective ORR electrocatalysts derived from MOF. [ABSTRACT FROM AUTHOR]

Review: 199 refs. [ABSTRACT FROM AUTHOR]