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1.
J Am Chem Soc ; 146(13): 9465-9475, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38507822

RESUMO

Dry reforming of methane (DRM) is a promising technique for converting greenhouse gases (namely, CH4 and CO2) into syngas. However, traditional thermocatalytic processes require high temperatures and suffer from low selectivity and coke-induced instability. Here, we report high-entropy alloys loaded on SrTiO3 as highly efficient and coke-resistant catalysts for light-driven DRM without a secondary source of heating. This process involves carbon exchange between reactants (i.e., CO2 and CH4) and oxygen exchange between CO2 and the lattice oxygen of supports, during which CO and H2 are gradually produced and released. Such a mechanism deeply suppresses the undesired side reactions such as reverse water-gas shift reaction and methane deep dissociation. Impressively, the optimized CoNiRuRhPd/SrTiO3 catalyst achieves ultrahigh activity (15.6/16.0 mol gmetal-1 h-1 for H2/CO production), long-term stability (∼150 h), and remarkable selectivity (∼0.96). This work opens a new avenue for future energy-efficient industrial applications.

2.
Small ; 17(21): e2100428, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33887127

RESUMO

Mesoporous metal sulfides (MMSs) with high surface areas and large pore volumes show great potential in many applications such as gas sensing, photodetection, and catalysis. However, the synthesis of MMSs is still challenging due to the uncontrollable fast precipitation between metal ions and S2- ions and the large volume contraction during the conversion of metal precursors to sulfides. Here, a general polymer-oriented acid-mediated self-assembly method to synthesize highly crystalline MMSs (e.g., ZnS, CdS, Ni3 S4 , CuS, and Znx Cd1- x S) by using polyethylenimine (PEI) as pore-forming agent is reported. In this method, acetic acid is designed as pH regulator and coordination agent to control the interactions between inorganic precursors and PEI, and adjust the reaction kinetics of metal ions and thioacetamide. This method endows a high degree of control over crystal structure and porous structure of MMSs. The surface areas and pore volumes of obtained MMSs are as high as 157 m2 g-1 and 1.149 cm3 g-1 , respectively. Benefiting from the abundant mesopores and homojunctions, mesoporous Zn0.56 Cd0.44 S shows a superior photocatalytic H2 generation rate of 14.3 mmol h-1 g-1 .

3.
Chemistry ; 27(60): 14790-14799, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34378261

RESUMO

Na3 V2 (PO4 )3 (NVP) has been regarded as a potential cathode material for sodium-ion batteries (SIBs) due to its excellent structural stability and rapid Na+ conductivity. However, its electrochemical performances are restricted by the large bulk structure and poor electronic conductivity. The construction of porous NVP materials is a powerful method to improve the electrochemical properties. This concept aims to provide an overview of recent progress of porous NVP materials for SIBs. Herein, the synthetic strategies and formation mechanisms of porous NVP materials as well as the relationship between the porous structures and electrochemical performances of NVP materials are reviewed. Furthermore, the challenges and prospects for the preparation of porous NVP materials in this field are outlined.

4.
Angew Chem Int Ed Engl ; 60(18): 10334-10341, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33591606

RESUMO

Na3 V2 (PO4 )3 (NVP) is regarded as a potential cathode material for sodium-ion batteries, whereas, its performance is usually limited by inherent low electronic conductivity and dense bulk structure. Herein, we develop a facile polymer stabilized droplet template strategy to synthesize porous single crystal structured NVP. The pore structures (macrostructures, hierarchically meso/macrostructures, and mesostructures), pore sizes (5-2000 nm), and specific surface areas (26-158 m2 g-1 ) of the samples can be readily controlled by tuning the sizes of droplet templates. The resultant hierarchically meso/macropores NVP demonstrates superior sodium storage performances, because its porous single crystal structure owns solid-liquid Na+ transmission mode, shortens ion diffusion distance and provides large electrode-electrolyte contact area, greatly facilitating fast ionic transport. We believe the presented method will supply a novel avenue to prepare porous single crystal structured materials for anticipative applications.

5.
Inorg Chem ; 59(7): 5063-5071, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32186863

RESUMO

The designed synthesis of nanotwin architectures and thus-induced phase junctions expresses huge significance for semiconductor photocatalysts. However, current methods of producing nanotwins mainly involve high-temperature thermal treatment and tedious reaction steps, generally resulting in large bulk structure with ill-defined morphology and low specific surface area. Here, we propose a mild ligand-assisted coordinative self-assembly method to synthesize uniform mesoporous ZnxCd1-xS nanospheres with ultrahigh surface areas (148-312 m2 g-1) and controllable diameter (90-370 nm). Moreover, the sample possesses abundant phase junctions induced by nanotwins containing both hexagonal and cubic segments. With the synergy of the twin-induced phase junctions and high surface area, the as-prepared mesoporous Zn0.82Cd0.18S nanospheres exhibit a remarkable photocatalytic H2 evolution rate of 13.46 mmol h-1 g-1 with free noble metal. The mechanism of photocarrier dynamics was studied by transient photovoltage spectroscopy, manifesting that the photocarrier lifetime of Zn0.82Cd0.18S is largely prolonged and therefore improves the charge separation efficiency and photocatalytic activity.

6.
Angew Chem Int Ed Engl ; 59(27): 11053-11060, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32173989

RESUMO

Mesoporous metal oxides (MMOs) have been demonstrated great potential in various applications. Up to now, the direct synthesis of MMOs is still limited to the solvent induced inorganic-organic self-assembly process. Here, we develop a facile, general, and high throughput solvent-free self-assembly strategy to synthesize a series of MMOs including single-component MMOs and multi-component MMOs (e.g., doped MMOs, composite MMOs, and polymetallic oxide) with high crystallinity and remarkable porous properties by grinding and heating raw materials. Compared with the traditional solution self-assembly process, the avoidance of solvents in this method not only greatly increases the yield of target products and synthesis efficiency, but also reduces the environmental pollution and the consumption of cost and energy. We believe the presented approach will pave a new avenue for scalable production of advanced mesoporous materials for various applications.

7.
Inorg Chem ; 57(20): 12953-12960, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30277383

RESUMO

Here, we present a series of experimental studies to encapsulate ultrasmall gold nanoparticles into mesoporous metal oxide via an in situ self-assembly method. Notably, the 2.0Au@mZnO catalyst (∼2.0 nm gold nanoparticles loading on mesoporous ZnO nanospheres) shows excellent catalytic activity for indane oxidation (120 °C, conversion 88.5%) and affords much high turnover frequencies (9521 h-1). The catalytic activity of these gold-based catalysts was found to be correlated with the size of gold nanoparticles and the types of metal oxide supports. With a decrease in gold nanoparticle size, the catalytic conversion efficiency of indane oxidation increased. In addition, such catalysts possessed high thermal and chemical stability and could be reused more than 10 times without a remarkable loss of catalytic activity.

8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(6): 1671-4, 2014 Jun.
Artigo em Zh | MEDLINE | ID: mdl-25358185

RESUMO

The microwave plasma torch (MPT) was used as the emission light source. Aqueous samples were introduced with a nebulizer and a desolvation system. A method for the determination of Na, Mg, Ca, Li and Sr in natural mineral drinking water by argon microwave plasma torch spectrometer (ArMPT spectrometer) was established. The effects of microwave power, flow rate of carrier gas and support gas were investigated in detail and these parameters were optimized. Under the optimized condition, the experiments for the determination of Na, Mg, Ca, Li and Sr in 11 kinds of bottled mineral drinking water were carried out by ArMPT spectrometer. The limit-of-detection (LOD) of Na, Mg, Ca, Li and Sr was found to be 4.4, 21, 56, 11 and 84 µg x mL(-1), respectively. Relative standard deviation (n = 6) was in the range of 1.30%-5.45% and standard addition recoveries were in the range of 84.6%-98.5%. MPT spectrometer was simpler, more convenient and of lower cost as compared to ICP unit. MPT spectrometer demonstrated its rapid analysis speed, accuracy, sensitivity and simultaneous multi element analysis ability during the analysis process. The results showed that MPT spectrometer was suitable for metal elements detection for natural mineral drinking water. This approach provides not only one way for resisting the illegal dealings, but also a security for the quality of drinking water. Moreover, the usability of MPT spectrometer in the field of food security; drug safety; clinical diagnostic is promised.


Assuntos
Água Potável/análise , Águas Minerais/análise , Cálcio , Lítio , Magnésio , Micro-Ondas , Sódio , Análise Espectral , Estrôncio
9.
J Pharm Pharmacol ; 75(7): 940-950, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37185938

RESUMO

OBJECTIVE: To study the effect of borneol combined with astragaloside IV and Panax notoginseng saponins (BAP) on promoting neurogenesis by regulating microglia polarization after cerebral ischaemia-reperfusion(CI/R) in rats. METHODS: A focal CI/R injury model was established. Evaluated the effects of BAP on ischaemic brain injury, on promoting neurogenesis, on inhibiting Inflammatory microenvironment and TLR4/MyD88/NFκB signalling pathway. A microglia oxygen-glucose deprivation reoxygenation (OGD/R) model was established that evaluated the effects of BAP on regulating the polarization of microglia and inflammatory microenvironment. RESULTS: BAP can inhibit the expression of TLR4, MyD88 and NFκB proteins, reduce IL-1ß and increase IL-10, reduce M1 type microglia and increase M2 microglia. The proliferation of neural stem cells increased, synaptic gap decreased, synaptic interface curvature increased, expression of SYN and PSD95 proteins increased, which improved the neurological dysfunction and reduced the volume of cerebellar infarction and nerve cell injury. CONCLUSION: BAP can reduce CI/R injury and promote neurogenesis, the effect is related to inhibition of the activation of TLR4/MyD88/NFκB, regulating the polarization of microglia from M1 type to M2 type and inhibition of inflammatory response.


Assuntos
Isquemia Encefálica , Panax notoginseng , Traumatismo por Reperfusão , Saponinas , Ratos , Animais , Microglia , Panax notoginseng/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Receptor 4 Toll-Like/metabolismo , Saponinas/farmacologia , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , NF-kappa B/metabolismo , Neurogênese , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo
10.
J Phys Chem Lett ; 13(5): 1272-1282, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35099983

RESUMO

Photocatalytic CO2 reduction into solar fuels is a promising technology for addressing energy and CO2 emission issues. Because of the superior properties in CO2 adsorption and activation, molecular diffusion, light absorption, and charge separation and transfer, porous materials have been developed into a multifunctional platform for photocatalytic CO2 reduction. In this Perspective, we first discuss the emerging trends of CO2 reduction in major inorganic porous materials-based photocatalysts, such as mesoporous materials, macroporous materials, hollow materials, hierarchically porous materials, and zeolites. Prospects and challenges in the development of porous materials-based photocatalysts are then outlined. Finally, we envision feasible solutions for the deployment of porous materials to enhance photocatalytic CO2 reduction performance.

11.
ChemSusChem ; 14(20): 4353, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34590789

RESUMO

Invited for this month's cover is the group of Zhen-An Qiao at the Jilin University. The image shows the application of 2D ordered mesoporous carbon/MXene heterostructures in supercapacitors. The Full Paper itself is available at 10.1002/cssc.202101374.

12.
Adv Sci (Weinh) ; 8(11): e2004943, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34105293

RESUMO

A general polymer-assisted spinodal decomposition strategy is used to prepare hierarchically porous sodium super ionic conductor (NASICON)-structured polyanion-type materials (e.g., Na3 V2 (PO4 )3 , Li3 V2 (PO4 )3 , K3 V2 (PO4 )3 , Na4 MnV(PO4 )3 , and Na2 TiV(PO4 )3 ) in a tetrahydrofuran/ethanol/H2 O synthesis system. Depending on the boiling point of solvents, the selective evaporation of the solvents induces both macrophase separation via spinodal decomposition and mesophase separation via self-assembly of inorganic precursors and amphiphilic block copolymers, leading to the formation of hierarchically porous structures. The resulting hierarchically porous Na3 V2 (PO4 )3 possessing large specific surface area (≈77 m2 g-1 ) and pore volume (≈0.272 cm3 g-1 ) shows a high specific capacity of 117.6 mAh g-1 at 0.1 C achieving the theoretical value and a long cycling life with 77% capacity retention over 1000 cycles at 5 C. This method presented here can open a facile avenue to synthesize other hierarchically porous polyanion-type materials.

13.
ChemSusChem ; 14(20): 4422-4430, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34350723

RESUMO

Two-dimensional transition metal carbonitrides (MXene) have demonstrated great potential in many fields. However, the serious aggregation and poor thermodynamic stability of MXene greatly hinder their applications. Here, an interface-induced self-assembly strategy to synthesize ordered mesoporous carbon/Ti3 C2 Tx heterostructures (OMCTs) was developed. In this method, the composite monomicelles formed by Pluronic F127 and low-molecular-weight phenolic resol self-assembled on the surface of Ti3 C2 Tx to prevent the restacking of Ti3 C2 Tx and maintain its thermostability. The obtained OMCTs possessed high specific surface areas (259-544 m2 g-1 ), large pore volumes (0.296-0.481 cm3 g-1 ), and excellent thermodynamic stability (up to 600 °C). Benefiting from these advantages, OMCTs serving as the electrode materials for supercapacitor exhibited superior supercapacitor performances, including high capacitance of 247 F g-1 at 0.2 A g-1 , satisfactory rate performance of 190 F g-1 at 5 A g-1 , and cyclability.

14.
Ann Transl Med ; 8(6): 319, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32355763

RESUMO

BACKGROUND: Clear cell renal cell carcinoma (ccRCC), characterized by high mortality, invasion, metastasis, recurrence and drug resistance, is the most common malignant tumor of the urinary system. A clear understanding of the underlying molecular mechanisms and its role during tumorigenesis of RCC can contribute to development of prognostic and targeted therapies. METHODS: We analyzed datasets from the public database, TCGA, Oncomine, for differential expression of ubiquitin-specific protease 2 (USP2), and further investigated its relationship with the clinical stage, pathological grade and prognosis of renal cancer. We used real-time quantitative PCR and western blot analysis to validate USP2 expression in clinical samples and renal cancer cell lines. Finally, we used CCK-8 and transwell assays to determine its effects on biological functions in cells. RESULTS: We observed significantly lower levels of USP2 mRNA in renal cancer, relative to normal, tissues across the four datasets from the Oncomine database (P<0.001), 533 cases from TCGA database (P<0.0001) and 30 pairs of clinical samples (P<0.0001). Similarly, a decreased USP2 protein expression in ccRCC was detected following immunohistochemical (IHC) and western blot analyses. Furthermore, the aberrant expression of USP2 resulted in significant relationship with clinical stage, pathological grade and lower USP2 mRNA expression was interrelated to poor prognosis of renal cell carcinoma. USP2 acted as an independent factor for ccRCC diagnosis, with an AUC of 0.8888 (95% CI: 0.8529 to 0.9246; P<0.0001). Exogenous restoration of USP2 in ccRCC cells resulted in repression of cell proliferation, migration, and invasion. CONCLUSIONS: Overall, these results show that USP2 acts as an anti-oncogene and an independent factor for ccRCC prognosis. Positive modulation of USP2 might lead to development of a novel strategy for ccRCC treatment.

15.
ACS Appl Mater Interfaces ; 11(49): 46205-46211, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31730328

RESUMO

Two-dimensional (2D) porous polymers have demonstrated great potential in gas capture and surface catalysis as well as energy storage and conversion. Current synthesis of 2D porous polymers strongly depends on the usage of templates or an additional exfoliation process. The resultant products have uncontrollable morphology and structure, low structure integrity, and relatively low yield. Herein, a facile and high-throughput solvent-induced polymerization strategy to prepare ultrathin free-standing 2D porous hyper-cross-linked polymer nanosheets with large surface area and high sulfur content by cross-linking steric hexakis(benzylthio)benzene and thiophene is reported. Using this approach, the morphologies (nanosheets and nanotubes) and specific surface areas (658-1150 m2 g-1) of porous hyper-cross-linked polymers can be simply tailored by adjusting the cross-linking degree between monomers. The as-synthesized porous hyper-cross-linked polymer nanotubes exhibit promising iodine capture performance, including a superior iodine uptake capacity (∼270 wt %) and a rapid equilibrium adsorption (within 60 min). This method will pave a new avenue for the synthesis of advanced 2D porous polymers for various applications.

16.
Adv Sci (Weinh) ; 6(6): 1801543, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30937257

RESUMO

Mesoporous metal oxides (MMOs) have attracted comprehensive attention in many fields, including energy storage, catalysis, and separation. Current synthesis of MMOs mainly involve use of surfactants as templates to generate mesopores and organic reagents as solvents to hinder hydrolysis and condensation of inorganic precursors, which is adverse to adjusting the interactions between surfactants and inorganic precursors. The resulting products have uncontrollable pore structure, crystallinity, and relatively lower surface areas. Here, a facile and general polymer-oriented self-assembly strategy to synthesize a series of MMOs (e.g., TiO2, ZrO2, NbO5, Al2O3, Ta2O5, HfO2, and SnO2) by using cationic polymers as porogens and metal alkoxides as metal oxide precursors in a robust aqueous synthesis system are reported. Nitrogen adsorption analysis and transmission electron microscopy confirm that the obtained MMOs have ultrahigh specific surface areas and large pore volumes (i.e., 733 m2 g-1 and 0.485 cm3 g-1 for mesoporous TiO2). Moreover, the structural parameters (surface area, pore size, and pore volume) and crystallinity can be readily controlled by tuning the interactions between cationic polymers and precursors. The as-synthesized crystalline mesoporous TiO2 exhibits promising performance in photocatalytic water splitting of hydrogen production and a high hydrogen production rate of 3.68 mol h-1 g-1.

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