Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 37
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Chem Asian J ; : e202400436, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38753576

RESUMEN

Prolonging the lifetime of SAPO-34 catalysts and enhancing their olefin selectivity in methanol-to-olefin (MTO) reactions are critical yet challenging objectives. Here, a series of hierarchical SAPO-34 catalysts were synthesized using a straightforward recrystallization method. The incorporation of triethylamine into the recrystallization mother liquor facilitated the formation of mesopores, achieving a high solid yield of up to 90%. Notably, the addition of phosphoric acid and ammonium polyvinyl phosphate alcohol during the recrystallization process significantly enhanced the crystallinity and regularity of the hierarchical SAPO-34 crystals, consequently increasing the mesopore size. Due to the substantially improved mass transfer efficiency and moderated acidity, the SP34-0.14P-0.06R catalysts exhibited a prolonged operational life of 344 min and 80.3% selectivity of ethylene and propylene at a WHSV of 2h-1. This performance markedly surpasses that of the parent SP34 catalyst, which demonstrated a lifetime of 136 min and a selectivity of 78.0%. Remarkably, the SP34-0.14P-0.06R maintained a lifetime of 166 minutes even at a high WHSV of 10h-1, which is more than 5-fold greater than that of the original microporous SP34. This research offers valuable insights into the design and development of hierarchically porous zeolites with high yields, enhancing the efficiency of MTO reactions and other applications.

2.
Mol Divers ; 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38709458

RESUMEN

Nitric oxide (NO), the smallest signaling molecule known, can be excessively produced by overexpressed inducible nitric oxide synthase (iNOS), and eventually leads to multiple inflammatory related diseases. Thus, reducing the overexpression of NO represents as very potential anti-inflammatory strategy. In current study, a series of compounds were designed and synthesized based on the hybridization of 7H-pyrrolo[2,3-d]pyrimidine and cinnamamide fragments in order to develop novel NO production inhibitors. Among them, compound S2h displayed a vigorous inhibitory activity on NO production with an IC50 value of 3.21 ± 0.67 µM, which was much lower than that of the positive control Nω-nitro-L-arginine (L-NNA, IC50 = 28.36 ± 3.13 µM). Due to its obeying Lipinski's and Veber's rules that guarantee compounds with good oral bioavailability, S2h effectively suppressed the paw swelling in carrageenan-induced mice. Additionally, compound S2h formed clear interactions with iNOS protein according to the docking analysis. Therefore, compounds S2h is a promising lead compound for further development of potent iNOS inhibitors or anti-inflammatory agents.

3.
Bioorg Chem ; 149: 107499, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38815476

RESUMEN

Janus Kinase 3 (JAK3) is important for the signaling transduction of cytokines in immune cells and is identified as potential target for treatment of rheumatoid arthritis (RA). Recently, we designed and synthesized two JAK3 inhibitors J1b and J1f, which featured with high selectivity but mild bioactivity. Therefore, in present study the structure was optimized to increase the potency. As shown in the results, most of the compounds synthesized showed stronger inhibitory activities against JAK3 in contrast to the lead compounds, among which 9a was the most promising candidate because it had the most potent effect in ameliorating carrageenan-induced inflammation of mice and exhibited low acute in vivo toxicity (MTD > 2 g/kg). Further analysis revealed that 9a was highly selective to JAK3 (IC50 = 0.29 nM) with only minimal effect on other JAK members (>3300-fold) and those kinases bearing a thiol in a position analogous to that of Cys909 in JAK3 (>150-fold). Meanwhile, the selectivity of JAK3 was also confirmed by PBMC stimulation assay, in which 9a irreversibly bound to JAK3 and robustly inhibited the signaling transduction with mild suppression on other JAKs. Moreover, it was showed that 9a could remarkably inhibited the proliferation of lymphocytes in response to concanavalin A and significantly mitigate disease severity in collagen induced arthritis. Therefore, present data indicate that compound 9a is a selective JAK3 inhibitor and could be a promising candidate for clinical treatment of RA.

4.
Adv Sci (Weinh) ; : e2400730, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654621

RESUMEN

Metal-enzyme integrated catalysts (MEICs) that combine metal and enzyme offer great potential for sustainable chemoenzymatic cascade catalysis. However, rational design and construction of optimal microenvironments and accessible active sites for metal and enzyme in individual nanostructures are necessary but still challenging. Herein, Pd nanoparticles (NPs) and Candida antarctica lipase B (CALB) are co-immobilized into the pores and surfaces of covalent organic frameworks (COFs) with tunable functional groups, affording Pd/COF-X/CALB (X = ONa, OH, OMe) MEICs. This strategy can regulate the microenvironment around Pd NPs and CALB, and their interactions with substrates. As a result, the activity of the COF-based MEICs in catalyzing dynamic kinetic resolution of primary amines is enhanced and followed COF-OMe > COF-OH > COF-ONa. The experimental and simulation results demonstrated that functional groups of COFs modulated the conformation of CALB, the electronic states of Pd NPs, and the affinity of the integrated catalysts to the substrate, which contributed to the improvement of the catalytic activity of MEICs. Further, the MEICs are prepared using COF with hollow structure as support material, which increased accessible active sites and mass transfer efficiency, thus improving catalytic performance. This work provides a blueprint for rational design and preparation of highly active MEICs.

5.
Small ; : e2401914, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38593297

RESUMEN

Metal halide perovskite quantum dots (QDs) are widely studied in the field of photocatalytic CO2 due to their strong light absorption and long carrier migration length. However, it can not exhibit high catalytic performance because of the radiative recombination and the lack of effective catalytic sites. Metal organic frameworks (MOFs) encapsulated QDs can not only solve the aforementioned problems, but also maintain their own unique characteristics with ultra-high specific surfaces area and abundant metal sites. In this work, lead-free bismuth-based halide perovskite QDs are encapsulated into Zr-based MOF (UiO-66), which combines the advantages with high power conversion efficiency of QDs and the high surface area and porosity of UiO-66. In addition, benefiting from the close contact between the Cs3Bi2Br9 QDs and the UiO-66 enables the photogenerated electrons in the QDs to be rapidly transferred to the MOF. As a result, the Cs3Bi2Br9@UiO-66 composite exhibits a higher yield for photocatalytic CO2 reduction than that of the prepared large-sized composite of Cs3Bi2Br9 and UiO-66.

6.
ChemSusChem ; : e202301868, 2024 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-38342756

RESUMEN

Photocatalysis is an eco-friendly method to regenerate nicotinamide (NADH) cofactors, which is essential for biotransformation over oxidoreductases. Organic polymers exhibit high stability, biocompatibility and functional designability as photocatalysts, but still suffering from rapid charge recombination. Herewith the heteroatom structural engineering of donor-π-acceptor (D-π-A) conjugated porous polymers were conducted to promote charge transfer and photocatalytic NADH regeneration. The electron delocalization of polymer photocatalysts can be readily tuned by changing the electron density of the donor unit, leading to faster charge separation and better photocatalytic performance. The optimum sulfur-doped polymer exhibits the highest NADH regeneration yield of 47.4 % in 30 min and 94.1 % in 4 h, which can drive the biocatalytic C=C bond reduction of 2-cyclohexen-1-one by ene-reductase, giving the corresponding cyclohexanone yield of 96.7 % in 10 h. Moreover, the oxygen-doped polymer, from biomass derived 2,5-diformylfuran, exhibits comparable photocatalytic activity to the sulfur-doped CPP, suggesting the potential of furan as alternative donor unit to thiophene.

7.
Small ; 20(13): e2308767, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37949814

RESUMEN

Dual single-atom catalysts (DSACs) are promising for breaking the scaling relationships and ensuring synergistic effects compared with conventional single-atom catalysts (SACs). Nevertheless, precise synthesis and optimization of DSACs with specific locations and functions remain challenging. Herein, dual single-atoms are specifically incorporated into the layer-stacked bulk-like carbon nitride, featuring in-plane three-coordinated Pd and interplanar four-coordinated Cu (Pd1-Cu1/b-CN) atomic sites, from both experimental results and DFT simulations. Using femtosecond time-resolved transient absorption (fs-TA) spectroscopy, it is found that the in-plane Pd features a charge decay lifetime of 95.6 ps which is much longer than that of the interplanar Cu (3.07 ps). This finding indicates that the in-plane Pd can provide electrons for the reaction as the catalytically active site in both structurally and dynamically favorable manners. Such a well-defined bi-functional cascade system ensures a 3.47-fold increase in CO yield compared to that of bulk-like CN (b-CN), while also exceeding the effects of single Pd1/b-CN and Cu1/b-CN sites. Furthermore, DFT calculations reveal that the inherent transformation from s-p coupling to d-p hybridization between the Pd site and CO2 molecule occurs during the initial CO2 adsorption and hydrogenation processes and stimulates the preferred CO2-to-CO reaction pathway.

8.
Heliyon ; 9(12): e22873, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38125480

RESUMEN

Objectives: The spread of SARS-Cov-2 remains a global concern along with the emergence of variants. This study aims to characterize the epidemiological and clinical features of hospitalized patients who were dragonized with five different variants of SARS-CoV-2 during the past 3 years. Methods: This retrospective study recruited 432 COVID-19 patients who were hospitalized in the First Hospital of Changsha from January 2020 to August 2022. Clinical records on clinical symptoms, laboratory profiles, and chest CT images was collected. The epidemiological and clinical features were compared between COVID-19 patients infected with either the wild-type, Omicron variant or pre- Omicron variants (e.g., Alpha, Beta, Delta). Results: A total of 432 laboratory-confirmed COVID-19 inpatients were dialogized during three waves, including 247 cases during the wild-type transmission period, 65 cases during the transmission period of pre-Omicron variants, and 119 cases during the transmission period of Omicron variants. The proportion of moderately or severely ill inpatients showed a gradual decline from the wild-type transmission period to the Omicron transmission period. The common symptoms of inpatients infected with SARS-CoV-2 wildtype strains included fever (67.61 %), cough (57.89 %), fatigue (33.60 %), and shortness of breath (12.15 %). In contrast, patients infected with other variants mostly showed upper respiratory symptoms. Based on chest CT images, a lower degree of acute pulmonary infection was observed among inpatients infected with the Omicron variants than those infected with the wild-type strain (31.09 % vs 93.12 %, p-value<0.01). Conclusions: Compared with the wild-type strain, SARS-CoV-2 variants of concern, especially the Omicron variant, mostly caused a lower degree of acute pulmonary infection, indicating the reduced disease severity and mortality among hospitalized COVID-19 patients.

9.
Front Immunol ; 14: 1196116, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37720234

RESUMEN

Introduction: Natural products have been shown to an important source of therapeutics for human disease. In this study, we aimed to identify natural compounds as potential therapeutics for epidermolysis bullosa acquisita (EBA), an autoimmune disease caused by autoantibodies to type VII collagen (COL7). Methods: Utilizing an in vitro experimental system, we screened a natural product library composed of 800 pure compounds for their inhibitory effect on COL7-anti-COL7 IgG immune complex (IC)-mediated neutrophil activation and on neutrophil-mediated tissue damage. Results: Three natural compounds, namely luteolin peracetate, gossypol, and gossypolone were capable in inhibiting the IC-induced neutrophil adhesion and oxygen burst in vitro. Furthermore, luteolin peracetate and gossypolone were able to inhibit the anti-COL7 IgG induced dermal-epidermal separation in an ex vivo model for EBA. Discussion: In summary, this study demonstrates that luteolin peracetate and gossypolone are potential therapeutics for experimental EBA, which deserves further investigation.


Asunto(s)
Productos Biológicos , Epidermólisis Ampollosa Adquirida , Gosipol , Humanos , Complejo Antígeno-Anticuerpo , Epidermólisis Ampollosa Adquirida/tratamiento farmacológico , Luteolina , Activación Neutrófila , Inmunoglobulina G
10.
Nat Commun ; 14(1): 3901, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37400443

RESUMEN

Understanding charge transfer dynamics and carrier separation pathway is challenging due to the lack of appropriate characterization strategies. In this work, a crystalline triazine/heptazine carbon nitride homojunction is selected as a model system to demonstrate the interfacial electron-transfer mechanism. Surface bimetallic cocatalysts are used as sensitive probes during in situ photoemission for tracing the S-scheme transfer of interfacial photogenerated electrons from triazine phase to the heptazine phase. Variation of the sample surface potential under light on/off confirms dynamic S-scheme charge transfer. Further theoretical calculations demonstrate an interesting reversal of interfacial electron-transfer path under light/dark conditions, which also supports the experimental evidence of S-scheme transport. Benefiting from the unique merit of S-scheme electron transfer, homojunction shows significantly enhanced activity for CO2 photoreduction. Our work thus provides a strategy to probe dynamic electron transfer mechanisms and to design delicate material structures towards efficient CO2 photoreduction.

11.
Biomater Sci ; 11(15): 5232-5239, 2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37338183

RESUMEN

Piezoelectric polymer nanofibers are attracting increasing attention in the stimulation of cell growth and proliferation in tissue engineering and wound healing applications. However, their intrinsic non-biodegradability in vivo hinders widespread applications in the biological fields. Herein, we designed, synthesized and characterized composite materials of silk fibroin (SF)/LiNbO3 (LN) nanoparticles/MWCNTs by electrospinning technology, which displayed good biocompatibility and comparable piezoelectric properties with an output current of up to 15 nA and output voltage of up to 0.6 V under pressure stimulation, remaining stable after 200 cycles of pressure release without significant decay. Meanwhile, the mechanical properties of the LN/CNTs/SF-nanofiber scaffolds (SF-NFSs) are also enhanced, with a tensile strength reaching 12.84 MPa and an elongation at break reaching 80.07%. Importantly, in vitro cell proliferation experiments showed that the LN/CNTs/SF-NFSs promoted cell proliferation at a rate of 43%. Accordingly, the mouse wound healing experiments further indicated that they could accelerate the healing of skin wounds in mice that were continuously moving. Therefore, SF-based piezoelectric nanofibrous scaffolds exhibit potential for use in rapid wound healing and this sheds light on smart treatment for tissue engineering in biomedicine.


Asunto(s)
Fibroínas , Nanofibras , Ratones , Animales , Andamios del Tejido , Cicatrización de Heridas , Ingeniería de Tejidos , Seda
12.
Chemistry ; 29(23): e202203706, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-36606747

RESUMEN

Metal-organic frameworks (MOFs) materials have become a research forefront in the field of photocatalytic CO2 reduction attributed to their ultra-high specific surface area, adjustable structure, and abundant catalytic active sites. Particularly, MOFs can be facilely tuned to match CO2 photoreduction by utilizing post-modification of metal nodes, functionalization of organic linkers, and combination with other active materials. Herein, the recent advances in the construction strategy of MOF-based photocatalysts materials for CO2 reduction are highlighted. Some systematic modification strategies on MOF-based photocatalysts are also discussed, such as modification of metal sites and organic ligands, construction of heterojunction, introduction of single/dual-atom, and strain engineering. Finally, the future development directions of MOF-based photocatalysts in the field of CO2 reduction are presented.

13.
Carbohydr Res ; 522: 108675, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36182822

RESUMEN

We propose a new approach for the synergistically catalytic conversion of cellulose to levulinic acid (LA) in water by SO3H-functionalized ionic liquid (SFIL) and lanthanide chloride (LnCl3). Compared with using 1-methyl-3-(3-sulfopropyl)imidazolium chloride ([MIMPS]Cl) only, the LA yield using [MIMPS]Cl and ErCl3 increased by 14.4% and 13.6% at 50 mol% of IL and 30 mol% of IL, respectively. Moreover, the combined [MIMPS]Cl and ErCl3 system can tolerate high concentrations of substrates and maintain high activity at eleven runs. We also investigated the effects of the cation structure of ionic liquids (alkyl chain length, hydroxyl groups on the side chains, and aromatic properties) on LA production. The observations can provide useful information for designing efficient ionic liquid catalysts for biomass utilization.


Asunto(s)
Líquidos Iónicos , Líquidos Iónicos/química , Celulosa/química , Cloruros , Agua/química , Catálisis
14.
Front Med (Lausanne) ; 9: 897695, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36148455

RESUMEN

Background: In-vitro models of differentiated primary human airway epithelial cells are a valuable tool to study severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Through the use of these models, it has been shown that the expression of SARS-CoV-2 entry genes in human airway epithelia is influenced by various factors such as age, sex, smoking status, and pathogenic conditions. In this study, we aimed to determine the effects of cell culture conditions and donor demographic and clinical characteristics on the expression of SARS-CoV-2 entry genes including angiotensin converting enzyme 2 (ACE2), transmembrane serine protease 2 (TMPRSS2), cathepsin L (CTSL), and tyrosine protein kinase receptor UFO (AXL) in primary airway epithelial cells. Methods: Eleven lung cancer patients with or without chronic obstructive pulmonary disease (COPD) or asthma were recruited. Human bronchial epithelial cells (HBEC) or small airway epithelial cells (SAEC) isolated from submerged or air-liquid interface (ALI) cultures were analyzed by quantitative real-time PCR. We also tested for correlations with clinical data. Results: In ALI cultures, the expression of AXL was significantly higher in HBEC than in SAEC. In addition, the expression of ACE2, TMPRSS2, and CTSL was significantly increased in both HBEC and SAEC differentiated under ALI conditions compared with the submerged culture. Negligible association was found between the expression of SARS-CoV-2 entry genes in SAEC and the age, sex, smoking status, and complication of COPD, asthma or hypertension of the cell donors. Conclusion: These results demonstrate that the expression of SARS-CoV-2 entry genes in differentiated primary airway epithelial cells in-vitro is much more influenced by individual culture conditions than by specific characteristics of individual donors.

15.
Angew Chem Int Ed Engl ; 61(40): e202208414, 2022 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-35920387

RESUMEN

Herein, using as-designed surface-mounted Bismuth-based metal-organic framework (Bi-MOF) on two-dimensional BiOBr support, as an operable platform for site-specific strain engineering to tailor the intermediate adsorption/desorption capability in CO2 photocatalytic conversion is proposed. Giant compressive strain up to 7.85 % is successfully induced on the surface-mounted Bi-MOF revealed by HRTEM images and geometric phase analysis as well as in situ Raman characterization, which largely downshifts the p band center of Bi nodes and intensifies their unsaturated state. In-depth explorations are put onto p-p (Bi 6p and CO2 /CO 2p) orbital hybridization. Taking the adsorption process as an example, the 1π and 7σ frontier molecule orbitals of CO2 2p for both the strain-free and strained models shift downwards the Fermi level, indicative of fast adsorption of CO2 . Meanwhile, strain engineering further induces new non-degenerate orbital overlapping near 1π and intensified overlapping of 7σ orbitals, stimulating the fast activation of absorbed CO2 molecules.

16.
Arthritis Res Ther ; 24(1): 209, 2022 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-36008863

RESUMEN

BACKGROUND: Recently, a novel humanized mouse model for systemic sclerosis (SSc) was established by transferring peripheral blood mononuclear cells (PBMC) from patients with SSc to Rag2-/-Il2rg-/- immunodeficient mice. Here, we aimed to investigate the role of T and B cells in this humanized mouse model. METHODS: T and B cells were depleted in vitro from freshly isolated PBMC using anti-CD3 and anti-CD19 magnetic microbeads, respectively. Subsequently, PBMC and T or B cell-depleted PBMC were transferred into Rag2-/-/Il2rg-/- mice via intraperitoneal injection. Twelve weeks after the transfer, mice were sacrificed and evaluated. RESULTS: Mice transferred with whole PBMC from SSc patients developed systemic inflammation in the lungs, kidneys, and liver, and 6 out of 11 mice died or had to be sacrificed during the experiment. By contrast, such inflammation and death were not observed in mice transferred with corresponding T or B cell-depleted PBMC. In line with this finding, transfer with whole PBMC restored the splenic white pulp composing of human T, B, and plasma cells and led to the production of a considerable amount of human autoantibodies in recipient mice, while those immunological features were rarely observed in mice that received T or B cell-depleted PBMC. In contrast to our previous findings demonstrating a transfer of the protective effect of a B cell therapy into the mouse, treatment of SSc patients with chemical immunosuppressive drugs did not affect the pathogenicity of PBMC. CONCLUSIONS: This study demonstrates that both T and B cells are indispensable for the pathogenesis of the PBMC transfer-induced mouse model for SSc.


Asunto(s)
Leucocitos Mononucleares , Esclerodermia Sistémica , Animales , Linfocitos B , Modelos Animales de Enfermedad , Humanos , Inflamación , Ratones
17.
ChemSusChem ; 15(13): e202201009, 2022 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-35723187

RESUMEN

Invited for this month's cover is the group of Yves Queneau at the University of Lyon. The cover image shows superb natural architectures with spherical symmetrical shapes evoking that of organized systems, micelles, and bubbles symbolizing creativity and imagination in the molecular design of biobased surfactants. The Review highlights the emerging use of 5-hydroxymethylfurfural and other biobased furans as scaffolds toward novel amphiphiles. The Review itself is available at 10.1002/cssc.202102660.


Asunto(s)
Furaldehído , Tensoactivos , Furaldehído/análogos & derivados , Furanos
18.
Ann Rheum Dis ; 2022 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35595388

RESUMEN

OBJECTIVE: To determine contributions and functions of autoantibodies (Abs) directed to the angiotensin receptor type 1 (AT1R), which are suggested to be involved in the pathogenesis of AT1R Abs-related diseases such as systemic sclerosis (SSc). METHODS: C57BL/6J mice were immunised with membrane-embedded human AT1R or empty membrane as control. Mice deficient for CD4+ or CD8+ T cells and B cells were immunised with membrane-embedded AT1R or an AT1R peptide proposed to be a dominant T cell epitope. A monoclonal (m)AT1R Ab was generated by hybridoma technique and transferred into C57BL/6J and AT1Ra/b knockout mice. The induced phenotype was examined by histology, immunohistochemistry, immunofluorescence, apoptosis assay and ELISA. In vitro, Abs responses towards AT1R were measured in cells of different origins and species. RESULTS: AT1R-immunised mice developed perivascular skin and lung inflammation, lymphocytic alveolitis, weak lung endothelial apoptosis and skin fibrosis accompanied by Smad2/3 signalling, not present in controls or mice deficient for CD4+ T and B cells. The AT1R peptide 149-172 provoked lung inflammation. Application of the mAT1R Ab induced skin and lung inflammation, not observed in AT1Ra/b knockout mice. In vitro, AT1R Abs activated rat cardiomyocytes and human monocytes, enhanced angiotensin II-mediated AT1R activation in AT1R-transfected HEK293 cells via AT1R binding and mAT1R Ab-activated monocytes mediated the induction of profibrotic markers in dermal fibroblasts. CONCLUSION: Our immunisation strategy successfully induced AT1R Abs, contributing to inflammation and, possibly, to fibrosis via activation of AT1R. Therefore, AT1R Abs are valuable targets for future therapies of SSc and other AT1R Ab-related diseases.

19.
Adv Mater ; 34(27): e2200929, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35476265

RESUMEN

Photoexcited dynamic modulation, maximizing the effective utilization of photoinduced electron-hole pairs, dominates the multiple electrons-involving reduction pathways for terminal CH4 evolution during CO2 photoreduction. Yet, the site-specific regulation of directional charge transfer by modification of an S-scheme heterojunction has seldom been discussed. Herein, an atomic-level tailoring strategy by anchoring single-atomic Co into CeO2 co-catalyst rather than carbon nitride supports, which can selectively favor CO2 -to-CH4 photoreduction, is reported. Through in situ dynamic tracking investigations, this study identifies that surface Co-embedded bimetallic CeCo conjunction is the key feature driving a strong interconnection of dynamical charge states through S-scheme heterojunctions. The Co-embedded modification into CeO2 co-catalysts is demonstrated to have a critical effect on directional charge control, accelerating the driving of electrons from the carbon nitride donations to site-specific Co hubs, which thereby promotes electronic transferability for electrons-involving CH4 formation. As a result, an unprecedented CH4 yield (181.7 µmol g-1 ) is obtained with a high turnover number (411.4) through a fully gas-solid reaction, demonstrating its potential toward targeted CH4 formation without adding any sacrificial agent.

20.
ChemSusChem ; 15(13): e202102660, 2022 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-35015340

RESUMEN

The use of 5-hydroxymethylfurfural (HMF), furfural, and furan as scaffolds for designing alternative surfactants is a rapidly developing research area. This Review gathers recent examples highlighting the variety of methods for grafting the necessary polar and non-polar appendages, exploiting the specific chemical reactivity of each of these platform molecules. While the furan (or tetrahydrofuran) backbone is maintained in some targeted amphiphiles, alternatives using rearranged HMF or furfural such as cyclopentanols or furanones have also been reported. This topic is an illustration of the diversification of the use of HMF and other biobased furanic platform molecules in the field of fine and specialty chemicals. The surfactants sector, which concerns some of the most largely consumed chemicals in everyday life, and still mostly produced from fossil resources, will benefit from such alternatives enabling increased renewable carbon content and structural innovation.


Asunto(s)
Furaldehído , Tensoactivos , Furaldehído/análogos & derivados , Furanos/química
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...