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G-quadruplexes (G4s) are peculiar nucleic acid secondary structures formed by DNA or RNA and are considered as fundamental features of the genome. Many proteins can specifically bind to G4 structures. There is increasing evidence that G4-protein interactions involve in the regulation of important cellular processes, such as DNA replication, transcription, RNA splicing, and translation. Additionally, G4-protein interactions have been demonstrated to be potential targets for disease treatment. In order to unravel the detailed regulatory mechanisms of G4-binding proteins (G4BPs), biochemical methods for detecting G4-protein interactions with high specificity and sensitivity are highly demanded. Here, we review recent advances in screening and validation of new G4BPs and highlight both their features and limitations.
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Quadruplex G , DNA/química , Replicação do DNA , RNA/químicaRESUMO
Recent studies have suggested that dogs were domesticated during the Last Glacial Maximum (LGM) in Siberia, which contrasts with previous proposed domestication centers (e.g. Europe, the Middle East, and East Asia). Ancient DNA provides a powerful resource for the study of mammalian evolution and has been widely used to understand the genetic history of domestic animals. To understand the maternal genetic history of East Asian dogs, we have made a complete mitogenome dataset of 120 East Asian canids from 38 archaeological sites, including 102 newly sequenced from 12.9 to 1â ka BP (1,000â years before present). The majority (112/119, 94.12%) belonged to haplogroup A, and half of these (55/112, 49.11%) belonged to sub-haplogroup A1b. Most existing mitochondrial haplogroups were present in ancient East Asian dogs. However, mitochondrial lineages in ancient northern dogs (northeastern Eurasia and northern East Asia) were deeper and older than those in southern East Asian dogs. Results suggests that East Asian dogs originated from northeastern Eurasian populations after the LGM, dispersing in two possible directions after domestication. Western Eurasian (Europe and the Middle East) dog maternal ancestries genetically influenced East Asian dogs from approximately 4â ka BP, dramatically increasing after 3â ka BP, and afterwards largely replaced most primary maternal lineages in northern East Asia. Additionally, at least three major mitogenome sub-haplogroups of haplogroup A (A1a, A1b, and A3) reveal at least two major dispersal waves onto the Qinghai-Tibet Plateau in ancient times, indicating eastern (A1b and A3) and western (A1a) Eurasian origins.
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Genoma Mitocondrial , Animais , Cães , Animais Domésticos/genética , Ásia Oriental , DNA Mitocondrial/genética , Variação Genética , Haplótipos , Mamíferos/genética , FilogeniaRESUMO
Central metal exchange can innovatively open the cavity of metal-organic frameworks (MOFs) by alternating the framework topology. Here, the single-crystal-to-single-crystal (SC-SC) transformation is reported from a Co-based MOF {[Co1.25 (HL)0.5 (Pz-NH2 )0.25 (µ3 -O)0.25 (µ2 -OH)0.25 (H2 O)]·0.125 Co·0.125 L·10.25H2 O}n (Co-MOF, L = 5,5'-(1H-2,3,5-triazole-1,4-diyl)diisophthalic acid) into two novel MOF materials, {[Cu1.75 L0.75 (Pz-NH2 )0.125 (µ3 -O)0.125 (µ2 -OH)0.25 (H2 O)0.375 ]â¢3CH3 CN}n (Cu-MOF) and {[Zn1.75 L0.625 (Pz-NH2 )0.25 (µ3 -O)0.25 (µ2 -O)0.25 (H2 O)1.25 ]â¢4CH3 CN}n (Zn-MOF), through exchanging the Co2+ in the MOF into Cu2+ or Zn2+ , respectively. The free Co2+ and L4- in the Co-MOF channels fuse with the skeleton during the CoâCu and CoâZn exchange processes, leading to the expansion of the channel space and the transformation of the secondary building units (SBUs) to form an adjustable skeleton. The nonlinear optical response results show that the MOFs generated by the exchange of the central metal exhibit different saturable absorption and the self-focusing effect. In addition, loading polypyrrole (PPy) into the MOFs can not only improve the stability of the MOFs but also further optimize the nonlinear optical behavior. This work suggests that SC-SC central metal exchange and the introduction of polymer molecules can tune the nonlinear optical response, which provides a new perspective for the future study of nonlinear optical materials.
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The directional arrangement of H2O molecules can effectively regulate the ordered protons transfer to improve transport efficiency, which can be controlled by the interaction between materials and H2O. Herein, a strategy to build a stable hydration layer in metal-organic framework (MOF) platforms, in which hydrophilic centers that can manipulate H2O molecules are implanted into MOF cavities is presented. The rigid grid-Ni-MOF is selected as the supporting material due to the uniformly distributed cavities and rigid structures. The Ag0 possesses potential combination ability with the hydrophilic substances, so it is introduced into the MOF as hydration layer centers. Relying on the strong interaction between Ag0 and H2O, the H2O molecules can rearrange around Ag0 in the cavity, which is intuitively verified by DFT calculation and molecular dynamics simulation. The establishment of a hydration layer in Ag@Ni-MOF regulates the chemical properties of the material and gives the material excellent proton conduction performance, with a proton conductivity of 4.86 × 10-2 S cm-1.
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Heterophylly is a phenomenon whereby an individual plant dramatically changes leaf shape in response to the surroundings. Hygrophila difformis (Acanthaceae; water wisteria), has recently emerged as a model plant to study heterophylly because of its striking leaf shape variation in response to various environmental factors. When submerged, H. difformis often develops complex leaves, but on land it develops simple leaves. Leaf complexity is also influenced by other factors, such as light density, humidity, and temperature. Here, we sequenced and assembled the H. difformis chromosome-level genome (scaffold N50: 60.43 Mb, genome size: 871.92 Mb), which revealed 36 099 predicted protein-coding genes distributed over 15 pseudochromosomes. H. difformis diverged from its relatives during the Oligocene climate-change period and expanded gene families related to its amphibious habit. Genes related to environmental stimuli, leaf development, and other pathways were differentially expressed in submerged and terrestrial conditions, possibly modulating morphological and physiological acclimation to changing environments. We also found that auxin plays a role in H. difformis heterophylly. Finally, we discovered candidate genes that respond to different environmental conditions and elucidated the role of LATE MERISTEM IDENTITY 1 (LMI1) in heterophylly. We established H. difformis as a model for studying interconnections between environmental adaptation and morphogenesis.
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Heavy metal ion wastewater is a pressing and inescapable issue that is closely related to human health and ecological security due to its toxicity, carcinogenicity, and the unmanageable property of this type of wastewater. Metal-Organic Frameworks (MOFs) are a class of crystalline nanoporous materials with flexible designability and controllability, showing great potential in the field of adsorption and purification of heavy metals in wastewater. In this Perspective, we first discuss the harm of different heavy metal ions and briefly expound virtues of MOFs for pollutant adsorption. Then, we mainly summarize the recent advances in the construction of different metal-based MOFs (Zr-based, Zn-based, Co-based, Al-based, etc.) and their research progress in heavy metal ions adsorption. Furthermore, various types of MOF additives can often be effectively applied for heavy metal ion adsorption by functional modification or with other materials composition. Additionally, several commonly used adsorption kinetics and isotherm models are also detailed to help an in-depth understanding of the adsorption mechanism. Finally, the challenges and opportunities of MOFs for heavy metal ion adsorption are additionally discussed, and this review may provide new insight for other potential water purification applications.
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Defect engineering plays a pivotal role in regulating electronic structure and facilitating charge transfer, yielding captivating effects on third-order nonlinear optical (NLO) properties. In this work, we utilized a mixed-linker strategy to intentionally disrupt the initial periodic arrangement of UiO-66 and construct defects. Specifically, we incorporated tetrakis(4-carboxyphenyl)porphyrin (TCPP) with an exceptionally electron-rich delocalization system into the framework of UiO-66 using a one-pot solvothermal method, ingeniously occupying the partial distribution sites of the Zr6 clusters. Compared to UiO-66, the NLO absorption and refraction performance of TCPP/UiO-66 were significantly improved. Additionally, due to the presence of nitrogen-rich sites that can accommodate metal ions in the porphyrin ring of TCPP, Co(II), Ni(II), Cu(II), and Zn(II) are introduced into TCPP/UiO-66, extending the d-π conjugation effect to further regulate the defects. The NLO absorption behavior transforms saturation absorption (SA) to reverse saturation absorption (RSA), while the refraction behavior shifts from self-defocusing to self-focusing. This work shows that defects can effectively regulate the electronic structure, while TCPP plays a crucial role in significantly enhancing electron delocalization.
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Bimetallic metal-organic frameworks (MOFs) capable of sensing external stimuli will provide more possibilities for further regulating third-order nonlinear optical (NLO) properties. In this work, we synthesized bimetallic MOFs (ZnCu-MOF and ZnCd-MOF) through central metal exchange using a photoresponsive Zn-MOF as a precursor. Compared with Zn-MOF, both ZnCu-MOF and ZnCd-MOF exhibit significantly enhanced third-order NLO absorption properties. This is mainly attributed to the introduction of metal ions with different electron configurations that can adjust the bandgap of MOFs and enhance electron delocalization, thus promoting electron transfer. Interestingly, the bimetallic MOFs show a transition from reverse saturation absorption (RSA) to saturation absorption (SA) after exposure to ultraviolet irradiation, as they retain the properties of directional photogenerated electron transfer. Photoresponsive bimetallic MOFs not only have the effect of bimetallic modulation of electronic structures but also have the characteristics of photoinduced electron transfer, exhibiting diversified optical properties. These findings provide a novel method for the development of multifunctional NLO materials.
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Phosphonate-based nerve agents, as a kind of deadly chemical warfare agent, are a persistent and evolving threat to humanity. Zirconium-based metal-organic frameworks (Zr-MOFs) are a kind of highly porous crystalline material that includes Zr-OH-Zr sites and imitates the active sites of the phosphotriesterase enzyme, representing significant potential for the adsorption and catalytic hydrolysis of phosphonate-based nerve agents. In this work, we present a new Zr-MOF, UiO-66-2I, which attaches two iodine atoms in the micropore of the MOF and exhibits excellent catalytic activity on the degradation of a nerve agent simulant, dimethyl 4-nitrophenyl phosphate (DMNP), as the result of the formation of halogen bonds between the phosphate ester bonds and iodine groups. Furthermore, various morphologies of UiO-66-2I, such as blocky-shaped nanoparticles (NPs), two-dimensional (2D) nanosheets, hexahedral NPs, stick-like NPs, colloidal microspheres, and colloidal NPs, have been obtained by adding acetic acid (AA), formic acid (FA), propionic acid (PA), valeric acid (VA), benzoic acid (BA), and trifluoroacetic acid (TFA) as modulators, respectively, and show different catalytic hydrolysis activities. Specifically, the catalytic activities follow the trend UiO-66-2I-FA (t1/2 = 1 min) > UiO-66-2I-AA-NP (t1/2 = 4 min) ≈ UiO-66-2I-VA (t1/2 = 4 min) > UiO-66-2I-BA (t1/2 = 5 min) > UiO-66-2I-PA (t1/2 = 15 min) > UiO-66-2I-TFA (t1/2 = 18 min). The experimental results show that the catalytic hydrolysis activity of Zr-MOF is regulated by the crystallinity, defect quantity, morphologies, and hydrophilicity of these samples, which synergistically affect the accessibility of catalytic sites and the diffusion of phosphate in the pores of Zr-MOFs.
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INTRODUCTION: The distinctions in the biological impacts of distinct forms of nicotine have become a prominent subject of current research. However, relatively little research has been done on the addictive effects of different forms of nicotine. METHODS: The aerosol self-administration device was briefly characterized by determining aerosol concentration, particle size, and distributional diffusion of the aerosol. And the aerosol self-administration model was constructed at 1, 5, and 10 mg/mL of nicotine to select the appropriate nicotine concentration. Subsequently, the model was used to explore the differences in aerosol self-administration behavior of freebase nicotine and nicotine salts and the behavioral differences after withdrawal. RESULTS: We successfully constructed mouse aerosol self-administration models at 1, 5, and 10 mg/mL nicotine concentrations. In the study of the difference in addictive behaviors between freebase nicotine and nicotine salts, mice with freebase nicotine and different nicotine salts showed varying degrees of drug-seeking behavior, with nicotine benzoate showing the strongest reinforcement. During the withdrawal phase, nicotine salts mice showed more robust anxiety-like behaviors. CONCLUSIONS: These results confirm the successful development and stability of the nicotine aerosol self-administration model. Furthermore, they demonstrated that nicotine salts enhance drug-seeking behavior to a greater extent than freebase nicotine, with nicotine benzoate exhibiting the most significant effects. IMPLICATIONS: In this study, an aerosol self-administered model of mice was constructed, which can be used not only for comparing the effects of freebase nicotine and nicotine salts on the behavior, but also for other addictive drugs, such as fentanyl and cannabis. In addition, this study shows that nicotine salts may be more addictive compared to freebase nicotine, which is a reference for the future use of nicotine salts in tobacco products such as e-cigarettes.
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INTRODUCTION: Smoking is one of the most important predisposing factors of intestinal inflammatory diseases. Heated tobacco product (HTP) is a novel tobacco category that is claimed to deliver reduced chemicals to human those reported in combustible cigarette smoke (CS). However, the effect of HTP on intestine is still unknown. METHODS: In the framework of Organization for Economic Co-operation and Development guidelines 413 guidelines, Sprague-Dawley rats were exposed to HTP aerosol and CS for 13 weeks. The atmosphere was characterized and oxidative stress and inflammation of intestine were investigated after exposure. Furthermore, the faeces we performed with 16S sequencing and metabolomics analysis. RESULTS: HTP aerosol and CS led to obvious intestinal damage evidenced by increased intestinal pro-inflammatory cytokines and oxidative stress in male and female rats After HTP and CS exposure, the abundance that obviously changed were Lactobacillus and Turiciacter in male rats and Lactobacillus and Prevotella in female rats. HTP mainly induced the metabolism of amino acids and fatty acyls such as short-chain fatty acids and tryptophan, while CS involved into the main metabolism of bile acids, especially indole and derivatives. Although different metabolic pathways in the gut mediated by HTP and CS, both to inflammation and oxidative stress were ultimately induced. CONCLUSIONS: HTP aerosol and CS induced intestinal damage mediated by different gut microbiota and metabolites, while both lead to inflammation and oxidative stress. IMPLICATIONS: The concentration of various harmful components in heated tobacco product aerosol is reported lower than that of traditional cigarette smoke, however, its health risk impact on consumers remains to be studied. Our research findings indicate that heated tobacco product and cigarette smoke inhalation induced intestinal damage through different metabolic pathways mediated by gut microbiome, indicating the health risk of heated tobacco product in intestine.
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Heavy metals (HMs) contamination of water bodies severely threatens human and ecosystem health. There is growing interest in the use of duckweeds for HMs biomonitoring and phytoremediation due to their fast growth, low cultivation costs, and excellent HM uptake efficiency. In this review, we summarize the current state of knowledge on duckweeds and their suitability for HM biomonitoring and phytoremediation. Duckweeds have been used for phytotoxicity assays since the 1930s. Some toxicity tests based on duckweeds have been listed in international guidelines. Duckweeds have also been recognized for their ability to facilitate HM phytoremediation in aquatic environments. Large-scale screening of duckweed germplasm optimized for HM biomonitoring and phytoremediation is still essential. We further discuss the morphological, physiological, and molecular effects of HMs on duckweeds. However, the existing data are clearly insufficient, especially in regard to dissection of the transcriptome, metabolome, proteome responses and molecular mechanisms of duckweeds under HM stresses. We also evaluate the influence of environmental factors, exogenous substances, duckweed community composition, and HM interactions on their HM sensitivity and HM accumulation, which need to be considered in practical application scenarios. Finally, we identify challenges and propose approaches for improving the effectiveness of duckweeds for bioremediation from the aspects of selection of duckweed strain, cultivation optimization, engineered duckweeds. We foresee great promise for duckweeds as phytoremediation agents, providing environmentally safe and economically efficient means for HM removal. However, the primary limiting issue is that so few researchers have recognized the outstanding advantages of duckweeds. We hope that this review can pique the interest and attention of more researchers.
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Metais Pesados , Poluentes do Solo , Humanos , Biodegradação Ambiental , Monitoramento Biológico , Ecossistema , Poluentes do Solo/análise , Metais Pesados/toxicidade , Metais Pesados/análise , SoloRESUMO
Site-specific imaging of target genes using CRISPR probes is essential for understanding the molecular mechanisms of gene function and engineering tools to modulate its downstream pathways. Herein, we develop CRISPR/Cas9-mediated signal amplification by exchange reaction (CasSABER) for programmable in situ imaging of low and nonrepetitive regions of the target gene in the cell nucleus. The presynthesized primer-exchange reaction (PER) probe is able to hybridize multiple fluorophore-bearing imager strands to specifically light up dCas9/sgRNA target-bound gene loci, enabling in situ imaging of fixed cellular gene loci with high specificity and signal-to-noise ratio. In combination with a multiround branching strategy, we successfully detected nonrepetitive gene regions using a single sgRNA. As an intensity-codable and orthogonal probe system, CasSABER enables the adjustable amplification of local signals in fixed cells, resulting in the simultaneous visualization of multicopy and single-copy gene loci with similar fluorescence intensity. Owing to avoiding the complexity of controlling in situ mutistep enzymatic reactions, CasSABER shows good reliability, sensitivity, and ease of implementation, providing a rapid and cost-effective molecular toolkit for studying multigene interaction in fundamental research and gene diagnosis.
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Loci Gênicos , RNA Guia de Sistemas CRISPR-Cas , Reprodutibilidade dos Testes , Sondas Moleculares , FluorescênciaRESUMO
Encapsulating photogenerated charge-hopping nodes and space transport bridges within metal-organic frameworks (MOFs) is a promising method of boosting the photocatalytic performance. Herein, this work embeds electron transfer media (9,10-bis(4-pyridyl)anthracene (BPAN)) in MOF cavities to build multi-level electron transfer paths. The MOF cavities are accurately regulated to investigate the significance of the multi-level electron transfer paths in the process of CO2 photoreduction by evaluating the difference in the number of guest media. The prepared MOFs, {[Co(BPAN)(1,4-dicarboxybenzene)(H2 O)2 ]·BPAN·2H2 O} and {[Co(BPAN)2 (4,4'-biphenyldicarboxylic acid)2 (H2 O)2 ]·2BPAN·2H2 O} (denoted as BPAN-Co-1 and BPAN-Co-2), exhibit efficient visible-light-driven CO2 conversion properties. The CO photoreduction efficacy of BPAN-Co-2 (5598 µmol g-1 h-1 ) is superior to that of most reported MOF-based catalysts. In addition, the enhanced CO2 photoreduction ability is supported by density functional theory (DFT). This work illustrates the feasibility of realizing charge separation characteristics in MOF catalysts at the molecular level, and provides new insight for designing high-performance MOFs for artificial photosynthesis.
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The greater duckweed (Spirodela polyrhiza 7498) exhibits trophic diversity (photoautotrophic, heterotrophic, photoheterotrophic, and mixotrophic growth) depending on the availability of exogenous organic carbon sources and light. Here, we show that the ability to transition between various trophic growth conditions is an advantageous trait, providing great phenotypic plasticity and metabolic flexibility in S. polyrhiza 7498. By comparing S. polyrhiza 7498 growth characteristics, metabolic acclimation, and cellular ultrastructure across these trophic modes, we show that mixotrophy decreases photosynthetic performance and relieves the CO2 limitation of photosynthesis by enhancing the CO2 supply through the active respiration pathway. Proteomic and metabolomic analyses corroborated that S. polyrhiza 7498 increases its intracellular CO2 and decreases reactive oxygen species under mixotrophic and heterotrophic conditions, which substantially suppressed the wasteful photorespiration and oxidative-damage pathways. As a consequence, mixotrophy resulted in a higher biomass yield than the sum of photoautotrophy and heterotrophy. Our work provides a basis for using trophic transitions in S. polyrhiza 7498 for the enhanced accumulation of value-added products.
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Adaptação Fisiológica , Araceae , Dióxido de Carbono/farmacologia , Dióxido de Carbono/metabolismo , Fotossíntese , ProteômicaRESUMO
In heterophyllous plants, leaf shape shows remarkable plasticity in response to environmental conditions. However, transgenic studies of heterophylly are lacking and the molecular mechanism remains unclear. Here, we cloned the KNOTTED1-LIKE HOMEOBOX family gene SHOOT MERISTEMLESS (STM) from the heterophyllous plant Hygrophila difformis (Acanthaceae). We used molecular, morphogenetic, and biochemical tools to explore its functions in heterophylly. HdSTM was detected in different organs of H. difformis, and its expression changed with environmental conditions. Heterologous, ectopic expression of HdSTM in Arabidopsis (Arabidopsis thaliana) increased leaf complexity and CUP-SHAPED COTYLEDON (CUC) transcript levels. However, overexpression of HdSTM in H. difformis did not induce the drastic leaf change in the terrestrial condition. Overexpression of HdSTM in H. difformis induced quick leaf variations in submergence, while knockdown of HdSTM led to disturbed leaf development and weakened heterophylly in H. difformis. HdCUC3 had the same spatiotemporal expression pattern as HdSTM. Biochemical analysis revealed a physical interaction between HdSTM and HdCUC3. Our results provide genetic evidence that HdSTM is involved in regulating heterophylly in H. difformis.
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Acanthaceae , Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Acanthaceae/metabolismo , Proteínas de Homeodomínio/metabolismo , Arabidopsis/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Meristema/genética , Meristema/metabolismoRESUMO
Pathogenic infection remains the primary threat to human health, such as the global COVID-19 pandemic. It is important to develop rapid, sensitive and multiplexed tools for detecting pathogens and their mutated variants, particularly the tailor-made strategies for point-of-care diagnosis allowing for use in resource-constrained settings. The rapidly evolving CRISPR/Cas systems have provided a powerful toolbox for pathogenic diagnostics via nucleic acid tests. In this review, we firstly describe the resultant promising class 2 (single, multidomain effector) and recently explored class 1 (multisubunit effector complexes) CRISPR tools. We present diverse engineering nucleic acid diagnostics based on CRISPR/Cas systems for pathogenic viruses, bacteria and fungi, and highlight the application for detecting viral variants and drug-resistant bacteria enabled by CRISPR-based mutation profiling. Finally, we discuss the challenges involved in on-site diagnostic assays and present emerging CRISPR systems and CRISPR cascade that potentially enable multiplexed and preamplification-free pathogenic diagnostics.
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RATIONALE: "Tobacco-free" or synthetic nicotine products have appeared in some markets, increasing potential health risks and regulatory compliance challenges. Currently, there are few reliable methods for the determination of authenticity of natural and synthetic nicotine. Analytical techniques based on stable isotopes have broad application prospects in the traceability and identification of agricultural products. METHODS: Tobacco leaves from four main tobacco production regions in China and different types of tobacco products were extracted with n-hexane and 5% sodium hydroxide to obtain nicotine extracts. Subsequent stable isotope mass spectrometry was performed by analyzing δ2 H, δ13 C, and δ15 N values of nicotine. RESULTS: Firstly, results from a batch of 233 samples indicated stable isotopes were closely related to climate and geographical locations and provide a basis for a determination of the origin of tobacco leaves. In addition, the δ2 H values had significant differences between natural and synthetic nicotine and the results indicate a δ2 H value of -163.0 could be the threshold for assessing synthetic and natural nicotine. Finally, a total of 239 results further validated the δ2 H value as a metric for source authentication of commercial tobacco products. CONCLUSIONS: Synthetic (S)-(-)-nicotine could be accurately and quickly identified using the method developed by measuring δ2 H values in a qualitative manner. To our knowledge, this is the first time a stable isotope mass spectrometry technique has been used for distinguishing the source of nicotine. This technique will aid in the accurate identification, labelling, and regulation of synthetic nicotine-based tobacco products.
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Nicotina , Produtos do Tabaco , Nicotiana , Isótopos/análise , Espectrometria de Massas , Isótopos de Carbono/análiseRESUMO
The incorporation of Lewis acid-base sites in catalysts has been considered as a significant approach to fabricating bifunctional catalysts with efficient catalytic activity for CO2 fixation. In this paper, a series of Hafnium-based metal-organic frameworks (Hf-MOFs), NU-912(Hf) and NU-912-X(Hf)-X (X = -NH2, -Br, -CN, and -I) derivatives assembled by Lewis acidic Hf6(µ3-O)4(µ3-OH)4(H2O)4(OH)4 (Hf6) clusters and Lewis base-attached organic linkers, are successfully synthesized by a facile ligand functionalization method. These isostructural Hf-MOFs, which exhibit diamond channels of 1.3 nm diameter, great chemical stability, and CO2 adsorption capacity, have been evaluated as catalysts for the CO2 cycloaddition reaction with epoxides. Catalytic experiments reveal that the micropore environments of these MOFs have an outstanding impact on catalytic activity. Remarkably, NU-912(Hf)-I serves as an efficient heterogeneous catalyst for this catalytic reaction under mild conditions due to the high density of Lewis acid Hf6 cluster centers and strong Lewis base functional groups, surpassing most of the reported MOF-based catalysts.
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Photocatalytic reduction of CO2 to value-added chemicals is known to be a promising approach for CO2 conversion. The design and preparation of ideal photocatalysts for CO2 conversion are of pivotal significance for the sustainable development of the whole society. In this work, we integrated two functional organic linkers to prepare a novel metal organic framework (MOF) photocatalyst {[Co(9,10-bis(4-pyridyl)anthracene)0.5(bpda)]·4DMF} (Co-MOF). The existence of anthryl and amino groups leads to a wide range of visible light absorption and efficient separation of photogenerated electrons. To extend the lifetime of photogenerated electrons in the photocatalytic system, we modified Co-MOF particles onto g-C3N4. As expected, Co-MOF/g-C3N4 composites exhibited an ultrahigh selectivity (more than 97%) in the photocatalytic process, and the highest CO production rate (1824 µmol/g/h) was 7.1 and 27.2 times of Co-MOFs and g-C3N4, respectively. What's more, we also discussed the reaction mechanism of the Co-MOF/g-C3N4 photocatalytic CO2 reduction, and this work paves the pathway for designing photocatalysts with ideal CO2 reduction performance.