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1.
Molecules ; 29(7)2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38611758

RESUMEN

Alzheimer's disease (AD) is a complex degenerative disease of the central nervous system that is clinically characterized by a progressive decline in memory and cognitive function. The pathogenesis of AD is intricate and not yet fully understood. Neuroinflammation, particularly microglial activation-mediated neuroinflammation, is believed to play a crucial role in increasing the risk, triggering the onset, and hastening the progression of AD. Modulating microglial activation and regulating microglial energy metabolic disorder are seen as promising strategies to intervene in AD. The application of anti-inflammatory drugs and the targeting of microglia for the prevention and treatment of AD has emerged as a new area of research interest. This article provides a comprehensive review of the role of neuroinflammation of microglial regulation in the development of AD, exploring the connection between microglial energy metabolic disorder, neuroinflammation, and AD development. Additionally, the advancements in anti-inflammatory and microglia-regulating therapies for AD are discussed.


Asunto(s)
Enfermedad de Alzheimer , Humanos , Enfermedad de Alzheimer/tratamiento farmacológico , Microglía , Enfermedades Neuroinflamatorias , Sistema Nervioso Central , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico
2.
ACS Nano ; 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38319748

RESUMEN

Fluoride-based solid electrolytes (SEs) have emerged as a promising component for high-energy-density rechargeable solid-state batteries (SSBs) in view of their wide electrochemical window, high air stability, and interface compatibility, but they still face the challenge of low ion conductivity and the lack of a desired structure for sodium metal SSBs. Here, we report a sodium-rich heterostructure fluoride SE, Na3GaF6-Ga2O3-NaCl (NGFOC-G), synthesized via in situ oxidation of liquid metal gallium and in situ chlorination using low-melting GaCl3. The distinctive features of NGFOC-G include single-crystal Na3GaF6 domains within an open-framework structure, composite interface decoration of Ga2O3 and NaCl with a concentration gradient, exceptional air stability, and high electrochemical oxidation stability. By leveraging the penetration of gallium at NaF grain boundaries and the in situ self-oxidation to form Ga2O3 nanodomains, the solid-phase reaction kinetics of NaF and GaF3 is activated for facilitating the synthesis of main component Na3GaF6. The introduction of a small amount of a chlorine source during synthesis further softens and modifies the boundaries of Na3GaF6 along with Ga2O3. Benefiting from the enhanced interface ion transport, the optimized NGFOC-G exhibits an ionic conductivity up to 10-4 S/cm at 40 °C, which is the highest level reported among fluoride-based sodium-ion SEs. This SE demonstrates a "self-protection" mechanism, where the formation of a high Young's modulus transition layer rich in NaF and Na2O under electrochemical driving prevents the dendrite growth of sodium metal. The corresponding Na/Na symmetric cells show minimal voltage hysteresis and stable cycling performance for at least 1000 h. The Na/NGFOC-G/Na3V2(PO4)3 cell demonstrates stable capacity release around 100 mAh/g at room temperature. The Na/NGFOC-G/FeF3 cell delivers a high capacity of 461 mAh/g with an excellent stability of conversion reaction cycling.

3.
Nano Lett ; 24(5): 1792-1800, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38278136

RESUMEN

A comprehensive approach for the construction of NIR-I/NIR-II nanofluorophores with exceptional brightness and excellent chemo- and photostability has been developed. This study first confirmed that the amphiphilic molecules with stronger hydrophobic moieties and weaker hydrophilic moieties are superior candidates for constructing brighter nanofluorophores, which are attributed to its higher efficiency in suppressing the intramolecular charge transfer/aggregation-caused fluorescence quenching of donor-acceptor-donor type fluorophores. The prepared nanofluorophore demonstrates a fluorescence quantum yield exceeding 4.5% in aqueous solution and exhibits a strong NIR-II tail emission up to 1300 nm. The superior performance of the nanofluorophore enabled the achievement of high-resolution whole-body vessel imaging and brain vessel imaging, as well as high-contrast fluorescence imaging of the lymphatic system in vivo. Furthermore, their potential for highly sensitive fluorescence detection of tiny tumors in vivo has been successfully confirmed, thus supporting their future applications in precise fluorescence imaging-guided surgery in the early stages of cancer.


Asunto(s)
Neoplasias , Humanos , Neoplasias/patología , Colorantes Fluorescentes/química , Imagen Óptica/métodos , Espectroscopía Infrarroja Corta/métodos
4.
J Mater Chem B ; 11(47): 11217-11221, 2023 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-37843833

RESUMEN

A polymeric engineering design principle is proposed for the construction of small-sized (∼20 nm) NIR-II AIEgen-doped nanodots (AIEdots) with high brightness and prolonged circulation time in blood vessels. With the utilization of the as-designed NIR-II AIEdots, the successful achievement of high-resolution NIR-II fluorescence imaging of tumor vessels and precise detection of abdominal metastases of ovarian cancer has been attained.


Asunto(s)
Colorantes Fluorescentes , Neoplasias Ováricas , Humanos , Femenino , Neoplasias Ováricas/diagnóstico por imagen , Neoplasias Ováricas/patología , Imagen Óptica , Polímeros
5.
Adv Mater ; 35(44): e2305472, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37437082

RESUMEN

Thermochromic fluorescent materials (TFMs) exhibit great potential in information encryption applications but are limited by low thermosensitivity, poor color tunability, and a wide temperature-responsive range. Herein, a novel strategy for constructing highly sensitive TFMs with tunable emission (450-650 nm) toward multilevel information encryption is proposed, which employs polarity-sensitive fluorophores with donor-acceptor-donor (D-A-D) type structures as emitters and long-chain alkanes as thermosensitive loading matrixes. The structure-function relationships between the performance of TFMs and the structures of both fluorescent emitters and phase-change molecules are systematically studied. Benefiting from the above design, the obtained TFMs exhibit over 9500-fold fluorescence enhancement toward the temperature change, as well as ultrahigh relative temperature sensitivity up to 80% K-1 , which are first confirmed. Thanks to the superior transducing performance, the above-prepared TFMs can be further developed as information-storage platforms within a relatively narrow interval of temperature variation, including temperature-dominated multicolored information display and multilevel information encryption. This work will not only provide a novel perspective for designing superior TFMs for information encryption but also bring inspiration to the design and preparation of other response-switching-type fluorescent probes with ultrahigh conversion efficiency.

6.
Front Microbiol ; 13: 1009689, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36386647

RESUMEN

Rhizosphere microbes play a vital role in plant health and defense against soil-borne diseases. Previous studies showed that maize-soybean relay strip intercropping altered the diversity and composition of pathogenic Fusarium species and biocontrol fungal communities in the soybean rhizosphere, and significantly suppressed soybean root rot. However, whether the rhizosphere bacterial community participates in the regulation of this intercropping on soybean root rot is not clear. In this study, the rhizosphere soil of soybean healthy plants was collected in the continuous cropping of maize-soybean relay strip intercropping and soybean monoculture in the fields, and the integrated methods of microbial profiling, dual culture assays in vitro, and pot experiments were employed to systematically investigate the diversity, composition, and function of rhizosphere bacteria related to soybean root rot in two cropping patterns. We found that intercropping reshaped the rhizosphere bacterial community and increased microbial community diversity, and meanwhile, it also recruited much richer and more diverse species of Pseudomonas sp., Bacillus sp., Streptomyces sp., and Microbacterium sp. in soybean rhizosphere when compared with monoculture. From the intercropping, nine species of rhizosphere bacteria displayed good antagonism against the pathogen Fusarium oxysporum B3S1 of soybean root rot, and among them, IRHB3 (Pseudomonas chlororaphis), IRHB6 (Streptomyces), and IRHB9 (Bacillus) were the dominant bacteria and extraordinarily rich. In contrast, MRHB108 (Streptomyces virginiae) and MRHB205 (Bacillus subtilis) were the only antagonistic bacteria from monoculture, which were relatively poor in abundance. Interestingly, introducing IRHB3 into the cultured substrates not only significantly promoted the growth and development of soybean roots but also improved the survival rate of seedlings that suffered from F. oxysporum infection. Thus, this study proves that maize-soybean relay strip intercropping could help the host resist soil-borne Fusarium root rot by reshaping the rhizosphere bacterial community and driving more beneficial microorganisms to accumulate in the soybean rhizosphere.

7.
J Agric Food Chem ; 70(36): 11258-11273, 2022 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-36041062

RESUMEN

This study aimed to identify the effects of isomaltodextrin (IMD) on sustaining the gut integrity and microbiota composition in a high-fat diet (HFD) with a lipopolysaccharide (LPS)-induced low-grade inflammation mouse model. The homeostasis of the immune response is important to reduce the risk of developing metabolic syndromes. The results of this study showed that pre-treatment of IMD at 5% (w/v) suppressed the concentration of endotoxin and pro-inflammatory mediators TNF-α, MCP-1, and IL-6 while increasing the adiponectin level in the plasma. Subsequently, IMD supplementation maintained the structural integrity and intestinal permeability by upregulating the tight junction protein expressions, leading to reducing D-mannitol concentration in the blood. In addition, dysbiosis was observed in mice induced by HFD plus LPS, suggesting that unhealthy dietary factors elicit metabolic endotoxemia and associated dysbiosis to impair the barrier function. However, IMD supplementation was shown to restore the microbial diversity, promote the growth of Bacteroides-Prevotella, and upregulate the related d-glucarate and d-galactarate degradation pathways, together demonstrating the benefits of IMD as a prebiotic able to promote energy homeostasis. Our results also showed that the blood lipid profile and glucose level in the low-grade inflammation mouse model were modulated by IMD. Moreover, IMD supplementation effectively prevented the metabolic disorder and modulated immune responses in inflamed white adipose tissues by inhibiting the macrophage infiltration and restoring the adiponectin, PPAR-γ, and IRS-1 expression. These findings provide strong evidence for IMD to be a potential prebiotic that acts to sustain a healthy gut microbiota composition and barrier function. By protecting against an unhealthy diet-impaired metabolic balance and maintaining immune homeostasis, IMD may affect the development of metabolic disorders.


Asunto(s)
Dieta Alta en Grasa , Enfermedades Metabólicas , Adiponectina , Animales , Dextrinas , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Disbiosis/tratamiento farmacológico , Disbiosis/prevención & control , Inflamación/inducido químicamente , Lipopolisacáridos/efectos adversos , Maltosa/análogos & derivados , Ratones , Ratones Endogámicos C57BL , Obesidad/metabolismo , Prebióticos
8.
Chem Commun (Camb) ; 56(37): 5062-5065, 2020 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-32249861

RESUMEN

Facile hydrothermally synthesized PbSnS2 nanosheets with various morphologies were developed to obtain high performance electrode materials for supercapacitors. A precipitation-dissolution mechanism was proposed to demonstrate the growth process of PbSnS2. The as-prepared nanosheets exhibited superior capacitance (678.8 F g-1 at 50 mV s-1) and a long cycle life (95.5% capacitance retention after 100 000 cycles at 5 A g-1).

9.
J Agric Food Chem ; 68(15): 4374-4386, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32250610

RESUMEN

A long-term exposure to lipopolysaccharides results in the gut inflammation and its impaired barrier function, leading to the development of metabolic disorders. In this study, the role of dietary heat killed Lactobacillus pentosus S-PT84 on preventing endotoxemia to maintain metabolic homeostasis was studied. We demonstrated that the treatment of L. pentosus S-PT84 improved the gut integrity by maintaining tight-junction protein expression, in order to suppress the infiltration of endotoxin into plasma. The systemic inflammatory responses were inhibited via reducing the secretion of TNF-α and MCP-1. Furthermore, the blood lipid profile and glucose level as well as adiponectin in both plasma and white adipose tissues (WAT) were preserved by L. pentosus S-PT84 through upregulation of PPAR-γ and IRS-1 expression in WAT. The above findings suggest that the metabolic homeostasis in mice treated with HFD and LPS was sustained by L. pentosus S-PT84, leading to reducing the early risk for progression into metabolic disorders.


Asunto(s)
Lactobacillus pentosus/fisiología , Enfermedades Metabólicas/tratamiento farmacológico , Probióticos/administración & dosificación , Animales , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Femenino , Humanos , Proteínas Sustrato del Receptor de Insulina/genética , Proteínas Sustrato del Receptor de Insulina/inmunología , Lipopolisacáridos/efectos adversos , Enfermedades Metabólicas/etiología , Enfermedades Metabólicas/inmunología , Enfermedades Metabólicas/microbiología , Ratones , Ratones Endogámicos C57BL , Receptores Activados del Proliferador del Peroxisoma/genética , Receptores Activados del Proliferador del Peroxisoma/inmunología , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/inmunología
10.
J Agric Food Chem ; 68(1): 138-146, 2020 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-31873011

RESUMEN

Chronic exposure to minute doses of endotoxin elicits intestinal inflammation and impairs the gut barrier function, potentially resulting in systemic inflammation with elevated concentrations of biomarkers associated with metabolic syndrome. This study aimed to investigate the preventive effects of the Rubus suavissimus S. Lee leaf extract in a model of low-grade systemic inflammation. The predominant compounds found in the leaf extract are gallic acids, ellagic acid, and rubusoside. Results of the present study showed that R. suavissimus leaf extract supplementation could help preserve intestinal barrier integrity by upregulating the expression of the tight junction proteins [e.g., zonula occluden-1 (ZO-1) and junctional adhesion molecule-1 (JAMA)] and mucin (MUC)-4 and also suppress the release of plasmatic proinflammatory cytokines, including tumor necrosis factor (TNF)-α, interleukin (IL)-6, and monocyte chemotactic protein (MCP)-1, while restoring the production of anti-inflammatory adiponectin. We subsequently determined that the leaf extract contributes to restoring glucose metabolic homeostasis through maintaining insulin sensitivity. Furthermore, our mechanistic finding demonstrated that the R. suavissimus leaf extract supplementation prevented systemic inflammation-driven impaired insulin sensitivity in white adipose tissues (WATs) by modulating the expression of peroxisome-proliferator-activated receptor-γ (PPAR-γ) and insulin receptor subset-1 (IRS-1). Altogether, our findings suggest that the above supplementation contributes to restoring immune and metabolic homeostasis to enhance the overall health of the host thereby preventing the early onset of metabolic disorders such as obesity and type 2 diabetes.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Inflamación/tratamiento farmacológico , Rubus/química , Animales , Citocinas/genética , Citocinas/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Modelos Animales de Enfermedad , Femenino , Humanos , Inflamación/inducido químicamente , Inflamación/genética , Inflamación/inmunología , Lipopolisacáridos/efectos adversos , Ratones , Ratones Endogámicos C57BL , PPAR gamma/genética , PPAR gamma/metabolismo , Hojas de la Planta/química , Proteínas de Uniones Estrechas/genética , Proteínas de Uniones Estrechas/metabolismo
11.
Nutrients ; 11(11)2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31731774

RESUMEN

:The purpose of this study was to identify the anti-inflammatory activity and mechanism of isomaltodextrin (IMD) in a C57BL/6NCrl mouse model with lipopolysaccharide (LPS)-induced systemic low-grade chronic inflammation and the effect on inflammation-induced potential risk of metabolic disorders. Pre-treatment of IMD decreased the production of pro-inflammatory mediators, TNF-α and MCP-1, and stimulated the production of the anti-inflammatory mediator, adiponectin by increasing the protein expression of peroxisome proliferator-activated receptor gamma (PPAR-γ) in the white adipose tissues. IMD administration reduced plasma concentrations of endotoxin, decreased macrophage infiltration into adipocytes, and increased expression of mucin 2, mucin 4, and the tight junction protein claudin 4. These results suggest that IMD administration exerted an anti-inflammatory effect on mice with LPS-induced inflammation, potentially by decreasing circulating endotoxin, suppressing pro-inflammatory mediators and macrophage infiltration, or by improving mucus or tight junction integrity. IMD exerted protein expression of insulin receptor subset-1 (IRS-1). IMD alleviated the disturbance of gut microflora in LPS-treated mice, as the number of B. bifidum, L. casei, and B. fragilis increased, and E. coli and C. difficile decreased, when compared to LPS-treated mice. The analysis of short chain fatty acids (SCFAs) further supported that the concentrations of acetic and butyric acids were positively correlated with IMD, as well as the number of beneficial bacteria. This study provides evidence that IMD possesses anti-inflammatory properties and exerts beneficial functions to prevent systemic low-grade chronic inflammation and reduces the risk of developing insulin resistance and associated metabolic diseases.


Asunto(s)
Antiinflamatorios/farmacología , Inflamación/tratamiento farmacológico , Polisacáridos/farmacología , Animales , Modelos Animales de Enfermedad , Inflamación/sangre , Inflamación/inducido químicamente , Mediadores de Inflamación/sangre , Lipopolisacáridos , Ratones , Ratones Endogámicos C57BL
12.
Small ; 14(18): e1702945, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29226633

RESUMEN

Integration of dual-barrel membrane patch-ion channel probes (MP-ICPs) to scanning ion conductance microscopy (SICM) holds promise of providing a revolutionized approach of spatially resolved chemical sensing. A series of experiments are performed to further the understanding of the system and to answer some fundamental questions, in preparation for future developments of this approach. First, MP-ICPs are constructed that contain different types of ion channels including transient receptor potential vanilloid 1 and large conductance Ca2+ -activated K+ channels to establish the generalizability of the methods. Next, the capability of the MP-ICP platforms in single ion channel activity measurements is proved. In addition, the interplay between the SICM barrel and the ICP barrel is studied. For ion channels gated by uncharged ligands, channel activity at the ICP barrel is unaffected by the SICM barrel potential; whereas for ion channels that are gated by charged ligands, enhanced channel activity can be obtained by biasing the SICM barrel at potentials with opposite polarity to the charge of the ligand molecules. Finally, a proof-of-principle experiment is performed and site-specific molecular/ionic flux sensing is demonstrated at single-ion-channel level, which show that the MP-ICP platform can be used to quantify local molecular/ionic concentrations.


Asunto(s)
Canales Iónicos/química , Microscopía/métodos , Transporte Iónico , Porosidad
13.
Faraday Discuss ; 193: 81-97, 2016 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-27711908

RESUMEN

We describe dual-barrel ion channel probes (ICPs), which consist of an open barrel and a barrel with a membrane patch directly excised from a donor cell. When incorporated with scanning ion conductance microscopy (SICM), the open barrel (SICM barrel) serves to measure the distance-dependent ion current for non-invasive imaging and positioning of the probe in the same fashion of traditional SICM. The second barrel with the membrane patch supports ion channels of interest and was used to investigate ion channel activities. To demonstrate robust probe control with the dual-barrel ICP-SICM probe and verify that the two barrels are independently addressable, current-distance characteristics (approach curves) were obtained with the SICM barrel and simultaneous, current-time (I-T) traces were recorded with the ICP barrel. To study the influence that the distance between ligand-gated ion channels (i.e., large conductance Ca2+-activated K+ channels/BK channels) and the ligand source (i.e., Ca2+ source) has on channel activations, ion channel activities were recorded at two fixed probe-substrate distances (Dps) with the ICP barrel. The two fixed positions were determined from approach curves acquired with the SICM barrel. One position was defined as the "In-control" position, where the probe was in close proximity to the ligand source; the second position was defined as the "Far" position, where the probe was retracted far away from the ligand source. Our results confirm that channel activities increased dramatically with respect to both open channel probability and single channel current when the probe was near the ligand source, as opposed to when the probe was far away from the ligand source.

14.
Tissue Barriers ; 3(4): e1105907, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26716077

RESUMEN

Direct recording of tight junction permeability is of pivotal importance to many biologic fields. Previous approaches bear an intrinsic disadvantage due to the difficulty of separating tight junction conductance from nearby membrane conductance. Here, we propose the design of Double whole-cell Voltage Clamp - Ion Conductance Microscopy (DVC-ICM) based on previously demonstrated potentiometric scanning of local conductive pathways. As proposed, DVC-ICM utilizes two coordinated whole-cell patch-clamps to neutralize the apical membrane current during potentiometric scanning, which in models described here will profoundly enhance the specificity of tight junction recording. Several potential pitfalls are considered, evaluated and addressed with alternative countermeasures.

15.
Nanoscale ; 7(45): 19080-91, 2015 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-26523891

RESUMEN

Nanopores have become a model system to understand transport properties at the nanoscale. We report experiments and modeling of ionic current in aprotic solvents with different dipole moments through conically shaped nanopores in a polycarbonate film and through glass nanopipettes. We focus on solutions of the salt LiClO4, which is of great importance in modeling lithium based batteries. Results presented suggest ion current rectification observed results from two effects: (i) adsorption of Li(+) ions to the pore walls, and (ii) a finite dipole moment rendered by adsorbed solvent molecules. Properties of surfaces in various solvents were probed by means of scanning ion conductance microscopy, which confirmed existence of an effectively positive surface potential in aprotic solvents with high dipole moments.

16.
Inorg Chem ; 54(15): 7388-401, 2015 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-26203675

RESUMEN

Manganese(II)-vanadate(V)/organic hybrids were prepared in high purity using four different N-donor organic ligands (2,6:2',2″-terpyridine = terpy, 2,2'-bipyrimidine = bpym, o-phenanthroline = o-phen, and 4,4'-bipyridine = 4,4'-bpy), and their crystalline structures, thermal stabilities, optical properties, photocatalytic activities and electronic structures were investigated as a function of the organic ligand. Hydrothermal reactions were employed that targeted a 1:2 molar ratio of Mn(II)/V(V), yielding four hybrid solids with the compositions of Mn(terpy)V2O6·H2O (I), Mn2(bpym)V4O12·0.6H2O (II), Mn(H2O)(o-phen)V2O6 (III), and Mn(4,4'-bpy)V2O6·1.16H2O (IV). The inorganic component within these hybrid compounds, that is, [MnV2O6], forms infinite chains in I and layers in II, III, and IV. In each case, the organic ligand preferentially coordinates to the Mn(II) cations within their respective structures, either as chelating and three-coordinate (mer isomer in I) or two-coordinate (cis isomers in II and III), or as bridging and two coordinate (trans isomer in IV). The terminating ligands in I (terpy) and III (o-phen) yield nonbridged "MnV2O6" chains and layers, respectively, while the bridging ligands in II (bpym) and IV (4,4'-bpy) result in three-dimensional, pillared hybrid networks. The coordination number of the ligand, that is, two- or three-coordinate, has the predominant effect on the dimensionality of the inorganic component, while the connectivity of the combined metal-oxide/organic network is determined by the chelating versus bridging ligand coordination modes. Each hybrid compound decomposes into crystalline MnV2O6 upon heating in air with specific surface areas from ∼7 m(2)/g for III to ∼41 m(2)/g for IV, depending on the extent of structural collapse as the lattice water is removed. All hybrid compounds exhibit visible-light bandgap sizes from ∼1.7 to ∼2.0 eV, decreasing with the increased dimensionality of the [MnV2O6] network in the order of I > II ≈ III > IV. These bandgap sizes are smaller by ∼0.1-0.4 eV in comparison to related vanadate hybrids, owing to the addition of the higher-energy 3d orbital contributions from the Mn(II) cations. Each compound also exhibits temperature-dependent photocatalytic activities for hydrogen production under visible-light irradiation in 20% methanol solutions, with threshold temperatures of ∼30 °C for III, ∼36 °C for I, and ∼40 °C for II, IV, and V4O10(o-phen)2. Hydrogen production rates are ∼142 µmol H2 g(-1)·h(-1), ∼673 µmol H2 g(-1)·h(-1), ∼91 µmol H2 g(-1)·h(-1), and ∼218 µmol H2 g(-1)·h(-1) at 40 °C, for I, II, III, and IV, respectively, increasing with the oxide/organic network connectivity. In contrast, the related V4O10(o-phen)2 exhibits a much lower photocatalytic rate of ∼36 H2 g(-1)·h(-1). Electronic structure calculations based on density-functional theory methods show that the valence band edges are primarily derived from the half-filled Mn 3d(5) orbitals in each, while the conduction band edges are primarily comprised of contributions from the empty V 3d(0) orbitals in I and II and from ligand π* orbitals in III. Thus, the coordinating organic ligands are shown to significantly affect the local and extended structural features, which has elucidated the underlying relationships to their photocatalytic activities, visible-light bandgap sizes, electronic structures, and thermal stabilities.

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