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1.
Angew Chem Int Ed Engl ; 63(22): e202403051, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38499468

RESUMEN

High open-circuit voltage (Voc) organic solar cells (OSCs) have received increasing attention because of their promising application in tandem devices and indoor photovoltaics. However, the lack of a precise correlation between molecular structure and stacking behaviors of wide band gap electron acceptors has greatly limited its development. Here, we adopted an asymmetric halogenation strategy (AHS) and synthesized two completely non-fused ring electron acceptors (NFREAs), HF-BTA33 and HCl-BTA33. The results show that AHS significantly enhances the molecular dipoles and suppresses electron-phonon coupling, resulting in enhanced intramolecular/intermolecular interactions and decreased nonradiative decay. As a result, PTQ10 : HF-BTA33 realizes a power conversion efficiency (PCE) of 11.42 % with a Voc of 1.232 V, higher than that of symmetric analogue F-BTA33 (PCE=10.02 %, Voc=1.197 V). Notably, PTQ10 : HCl-BTA33 achieves the highest PCE of 12.54 % with a Voc of 1.201 V due to the long-range ordered π-π packing and enhanced surface electrostatic interactions thereby facilitating exciton dissociation and charge transport. This work not only proves that asymmetric halogenation of completely NFREAs is a simple and effective strategy for achieving both high PCE and Voc, but also provides deeper insights for the precise molecular design of low cost completely NFREAs.

2.
Inorg Chem ; 62(46): 18809-18813, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37943673

RESUMEN

The design of a highly and photomodulated proton conductor is important for advanced potential applications in chemical sensors and bioionic functions. In this work, a metal-organic framework (MOF; Gd-NO2) with high proton conductivity is synthesized with a photosensitive ligand of 5-nitroisophthalic acid (BDC-NO2), and it provides remote-control photomodulated proton-conducting behavior. The proton conduction of Gd-NO2 reaches 3.66 × 10-2 S cm-1 at 98% relative humidity (RH) and 25 °C, while it decreases by ∼400 times after irradiation with a 355 nm laser. The newly generated and disappearing FT-IR characteristic peaks reveal that this photomodulated process is realized by the photoinduced transformation from BDC-NO2 to 5-nitroso-isophthalic acid (BDC-NO). According to density functional theory, the smaller electronegativity of the -NO group, the longer distance of the hydrogen bond between BDC-NO and H2O molecules, and the lower water adsorption energy of BDC-NO indicate that the irradiated sample possesses a poorer hydrophilicity and has difficulty forming rich hydrogen-bonded networks, which results in the remarkable decrease of proton conductivity.

3.
Inorg Chem ; 61(23): 8662-8669, 2022 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-35617168

RESUMEN

Cluster-based framework metal iodides have diverse structures and excellent luminescence properties, and show promising applications in sensing and solid-state lighting. However, the design and synthesis of these materials remain great challenges because excess I- ions introduced into the synthesis systems decrease the condensation degree of M-I units. In this work, a new strategy is developed to control the condensation behavior of Ag-I units, and a new silver-rich cluster-based framework iodide [DabcoAg8I6(SPh)2]n (1) (Dabco = 1,4-diazabicyclo [2.2.2] octane) has been synthesized under solvothermal conditions in the presence of silver thiophenolate (AgSPh)n. Compound 1 features a three-dimensional (3-D) cluster-based framework with a pillared layer structure composed of cationic [Ag8I6]2+ clusters bridged by SPh- and Dabco, and displays low-temperature dual emission and luminescence thermochromism.

4.
Biochem Biophys Res Commun ; 510(1): 97-103, 2019 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-30661787

RESUMEN

SRPIN340, a selective serine-arginine protein kinase 1/2 (SRPK1/2) inhibitor, has been shown to have antiviral and anti-angiogenesis effects. However, its role in the heart is unknown. The present study explored the role of SRPIN340 in myocardial protection and the related mechanisms. During challenge with H2O2, cardiomyocytes (CMs) pretreated with SRPIN340 showed strikingly more injury tolerance, which was manifested as reduced lactate dehydrogenase (LDH) release and lower apoptotic index. Further research showed that SRPIN340 activated AKT under basal conditions, and AKT inhibition abolished the protective effects of SRPIN340 treatment during H2O2 stress. The protective effect of SRPIN340 was also demonstrated in perfused rat hearts subjected to ischemia/reperfusion (I/R). Collectively, our results reveal the beneficial effects of SRPIN340 against H2O2-induced oxidative damage in CMs and I/R-induced injury in a Langendorff heart model, supporting a potential application of SRPIN340 in the clinically relevant context of reperfusion. The effectiveness of SRPIN340 may be attributed to AKT signal activation.


Asunto(s)
Miocardio , Niacinamida/análogos & derivados , Estrés Oxidativo/efectos de los fármacos , Piperidinas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Animales , Corazón/efectos de los fármacos , Peróxido de Hidrógeno/farmacología , Daño por Reperfusión Miocárdica/prevención & control , Niacinamida/farmacología , Niacinamida/uso terapéutico , Piperidinas/uso terapéutico , Sustancias Protectoras/farmacología , Sustancias Protectoras/uso terapéutico , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Transducción de Señal
5.
J Nanosci Nanotechnol ; 19(9): 5707-5712, 2019 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-30961728

RESUMEN

Porous photocatalysts have attracted significant attention for their large specific surface area, numerous surface catalytic active sites, and high photocatalytic activity. In this study, porous SrTiO3/TiO2 composites were successfully fabricated through a hydrothermal approach utilizing porous TiO2 as a substrate. The as-synthesized SrTiO3/TiO2 composites were then characterized by X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy, Brunauer-Emmett-Teller (BET), and ultraviolet-visible spectroscopy (UV-Vis) analysis. The results of SEM and BET indicate that such composites have a porous structure and large surface area. Compared to unadulterated TiO2, SrTiO3 /TiO2 composites exhibit higher photocatalytic performance for the photodegradation of rhodamine B under UV-Vis irradiation. Additionally, it was found that when the content of SrTiO3 reaches 20%, it achieves the maximum photodegradation efficiency of 98.6% under UV-Vis irradiation over 60 min. These results demonstrate that SrTiO3/TiO2 composites are a promising material in terms of environmental cleanliness.

6.
Adv Mater ; : e2404660, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38890789

RESUMEN

In the recent advances of organic solar cells (OSCs), quinoxaline (Qx)-based nonfullerene acceptors (QxNFAs) have attracted lots of attention and enabled the recorded power conversion efficiency approaching 20%. As an excellent electron-withdrawing unit, Qx possesses advantages of many modifiable sites, wide absorption range, low reorganization energy, and so on. To develop promising QxNFAs to further enhance the photovoltaic performance of OSCs, it is necessary to systematically summarize the QxNFAs reported so far. In this review, all the focused QxNFAs are classified into five categories as following: SM-Qx, YQx, fused-YQx, giant-YQx, and polymer-Qx according to the molecular skeletons. The molecular design concepts, relationships between the molecular structure and optoelectronic properties, intrinsic mechanisms of device performance are discussed in detail. At the end, the advantages of this kind of materials are summed up, the molecular develop direction is prospected, the challenges faced by QxNFAs are given, and constructive solutions to the existing problems are advised. Overall, this review presents unique viewpoints to conquer the challenge of QxNFAs and thus boost OSCs development further toward commercial applications.

7.
RSC Adv ; 14(7): 4568-4574, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38312728

RESUMEN

Photoelectrochemical water splitting (PEC-WS) has attracted considerable attention owing to its low energy consumption and sustainable nature. Constructing semiconductor heterojunctions with controllable band structure can effectively facilitate photogenerated carrier separation. In this study, a FTO/ZnO/Cu2O/Ag@SiO2 photoanode with a Cu2O/ZnO p-n heterojunction and Ag@SiO2 nanoparticles is constructed to investigate its PEC-WS performance. Compared with a bare ZnO photoanode, the photocurrent density of the FTO/ZnO/Cu2O/Ag@SiO2 photoanode (0.77 mA cm-2) at 1.23 VRHE exhibits an increment of 88%, and a cathodic shift of 0.1 V for the on-set potential (0.4 VRHE). Detailed photoelectrochemical analyses reveal that the Cu2O/ZnO p-n heterojunction formed between Cu2O and ZnO can effectively promote photogenerated carrier separation. The surface plasmonic effect of the Ag@SiO2 nanoparticles can further promote the photogenerated carrier transfer efficiency, which synergistically improves the PEC-WS performance.

8.
Adv Mater ; 36(21): e2313772, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38402409

RESUMEN

Fiber-shaped aqueous zinc-ion batteries (FAZIBs) with intrinsic safety, highcapacity, and superb omnidirectional flexibility hold promise for wearable energy-supply devices. However, the interfacial separation of fiber-shaped electrodes and electrolytes caused by Zinc (Zn) stripping process and severe Zn dendrites occurring at the folded area under bending condition seriously restricts FAZIBs' practical application. Here, an advanced confinement encapsulation strategy is originally reported to construct dual-layer gel electrolyte consisting of high-fluidity polyvinyl alcohol-Zn acetate inner layer and high-strength Zn alginate outer layer for fiber-shaped Zn anode. Benefiting from the synergistic effect of inner-outer gel electrolyte and the formation of solid electrolyte interphase on Zn anode surface by lysine additive, the resulting fiber-shaped Zn-Zn symmetric cell delivers long cycling life over 800 h at 1 mA cm-2 with dynamic bending frequency of 0.1 Hz. The finite element simulation further confirms that dual-layer gel electrolyte can effectively suppress the interfacial separation arising from the Zn stripping and bending process. More importantly, a robust twisted fiber-shaped Zn/zinc hexacyanoferrate battery based on dual-layer gel electrolyte is successfully assembled, achieving a remarkable capacity retention of 97.7% after bending 500 cycles. Therefore, such novel dual-layer gel electrolyte design paves the way for the development of long-life fiber-shaped aqueous metal batteries.

9.
Cardiovasc Res ; 120(8): 954-970, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38252884

RESUMEN

AIMS: Adiponectin is an adipocyte-derived circulating protein that exerts cardiovascular and metabolic protection. Due to the futile degradation of endogenous adiponectin and the challenges of exogenous administration, regulatory mechanisms of adiponectin biosynthesis are of significant pharmacological interest. METHODS AND RESULTS: Here, we report that 5-diphosphoinositol 1,2,3,4,6-pentakisphosphate (5-InsP7) generated by inositol hexakisphosphate kinase 1 (IP6K1) governed circulating adiponectin levels via thiol-mediated protein quality control in the secretory pathway. IP6K1 bound to adiponectin and DsbA-L and generated 5-InsP7 to stabilize adiponectin/ERp44 and DsbA-L/Ero1-Lα interactions, driving adiponectin intracellular degradation. Depleting 5-InsP7 by either IP6K1 deletion or pharmacological inhibition blocked intracellular adiponectin degradation. Whole-body and adipocyte-specific deletion of IP6K1 boosted plasma adiponectin levels, especially its high molecular weight forms, and activated AMPK-mediated protection against myocardial ischaemia-reperfusion injury. Pharmacological inhibition of 5-InsP7 biosynthesis in wild-type but not adiponectin knockout mice attenuated myocardial ischaemia-reperfusion injury. CONCLUSION: Our findings revealed that 5-InsP7 is a physiological regulator of adiponectin biosynthesis that is amenable to pharmacological intervention for cardioprotection.


Asunto(s)
Adiponectina , Ratones Endogámicos C57BL , Ratones Noqueados , Daño por Reperfusión Miocárdica , Animales , Adiponectina/metabolismo , Adiponectina/genética , Adiponectina/sangre , Daño por Reperfusión Miocárdica/prevención & control , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/patología , Daño por Reperfusión Miocárdica/genética , Daño por Reperfusión Miocárdica/sangre , Daño por Reperfusión Miocárdica/enzimología , Fosfotransferasas (Aceptor del Grupo Fosfato)/metabolismo , Fosfotransferasas (Aceptor del Grupo Fosfato)/genética , Fosfatos de Inositol/metabolismo , Adipocitos/metabolismo , Adipocitos/enzimología , Adipocitos/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/metabolismo , Proteínas Quinasas Activadas por AMP/genética , Masculino , Ratones , Modelos Animales de Enfermedad , Transducción de Señal , Proteolisis , Humanos
10.
Dalton Trans ; 52(36): 12869-12877, 2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37622489

RESUMEN

Aqueous rechargeable zinc ion batteries (ARZIBs) are ideal for massive and longstanding energy storage applications because of their excellent security and low operation cost. Nevertheless, ARZIBs are subject to the severe corrosion reaction of zinc metal anodes that is derived from the thermodynamic unsteadiness of the zinc anodes in aqueous solution, as well as zinc dendrite growth originating from uncontrolled zinc deposition. Herein, we created a separator by coating a thin piece of polypropylene (PP) with a compound consisting of zinc trifluoromethanesulfonate [Zn(OTf)2] and poly(vinylidene fluoride-hexafluoropropylene (PVDF-HFP). Consequently, the severe corrosion reaction of the zinc metal anodes and the profuse formation of zinc dendrites were effectively mitigated by the novel PP separator, which prolonged the lifetime of the zinc metal anodes. When a zinc metal plating layer was used with preferential (002) crystallographic orientation, the cyclic performance over 1100 h of the symmetrical Zn∥Zn battery based on the novel separator was steady. Additionally, the Zn∥MnO2 batteries exhibited an impressive specific capacity and competitive long durability of 75.5% over 500 cycles at a current density of 0.1 A g-1. With this work, we intend to set the standard for designing novel separators in the construction of advanced zinc anodes for high-performance ARZIBs.

11.
Dalton Trans ; 52(32): 11203-11212, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37522640

RESUMEN

As one of the most popular photoanode materials, hematite (α-Fe2O3) has obvious advantages in the field of photoelectrochemical water splitting (PEC-WS). However, it is difficult to achieve excellent PEC-WS performance without loading a cocatalyst serving as an electron/hole collector to promote photogenerated carrier separation. In this work, FTO/Sn@α-Fe2O3 photoanodes are modified with ZnCo-ZIF and ZnCoOOH bimetallic catalysts to obtain FTO/Sn@α-Fe2O3/Zn0.5Co0.5-ZIF and FTO/Sn@α-Fe2O3/Zn0.46Co0.54OOH photoanodes. Their photocurrent densities reach 2.6 mA cm-2 and 2.3 mA cm-2 at 1.23 VRHE, respectively. The detailed mechanism studies demonstrate that both ZnCoOOH and ZnCo-ZIF can effectively decrease the transfer resistance, increase the Fe2+/Fe3+ ratio and reduce the charge recombination of the α-Fe2O3 film, which synergistically improves the PEC-WS performance. Compared with ZnCoOOH, the ZnCo-ZIF exhibits better photogenerated carrier transfer efficiency and catalytic performance, which mainly can be attributed to the improved binding energy between the ZnCo-ZIF catalyst and the α-Fe2O3 film. This work provides a simple and feasible strategy for constructing bimetallic catalysts and deepens the understanding of different types of bimetallic catalysts for high-performance PEC-WS systems.

12.
Dalton Trans ; 52(35): 12308-12317, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37591825

RESUMEN

Surface catalyst engineering can effectively improve the photoelectrochemical water splitting (PEC-WS) performance of semiconductor photoelectrodes. In situ surface functional treatments can effectively reduce interface defects and improve photogenerated carrier transport. In this study, FTO/Sn@α-Fe2O3/FeOOH photoanodes were modified with in situ sulfide/nitride/phosphide treatments to improve their PEC-WS performance. Compared with the pure α-Fe2O3 photoanode, the photocurrent densities of FTO/Sn@α-Fe2O3/FeOOH photoanodes after sulfide/nitride/phosphide treatments increased from 0.88 to 3.38 mA cm-2 at 1.23 VRHE. The onset potential showed a cathode shift of 0.1 V. Photoelectrochemical analyses and theoretical calculation demonstrated that the surface engineering by sulfide/nitride/phosphide treatments can significantly reduce surface defects, enhance electrical conductivity and promote photogenerated carrier separation and transfer efficiency by regulating interface charge transfer, binding energy and internal electric field. The formation of an FeSx catalyst and N/P coordination complexes in the sulfide/nitride/phosphide processes on the surface of α-Fe2O3 photoanodes can effectively reduce photogenerated carrier recombination. This work provides experimental and theoretical support for surface structure design and improved photoelectric conversion performance of semiconductor photoelectrode materials.

13.
Nanotechnology ; 23(48): 485603, 2012 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-23128027

RESUMEN

A new strategy for preparing luminescent and intelligent gold nanodots based on supramolecular self-assembly is described in this paper. The supramolecular self-assembly was initiated through electrostatic interactions and ion pairing between palmitic acid and hyperbranched poly(ethylenimine). The resulting structures not only have the dynamic reversible properties of supramolecules but also possess torispherical and highly branched architectures. Thus they can be regarded as a new kind of ideal nanoreactor for preparing intelligent Au nanodots. By preparing Au nanodots within this kind of supramolecular self-assembly, the environmental sensitivity of intelligent polymers and the optical, electrical properties of Au nanodots can be combined, endowing the Au nanodots with intelligence. In this paper, a supramolecular self-assembly process based on dendritic poly(ethylenimine) and palmitic acid was designed and then applied to prepare fluorescent and size-controlled Au nanodots. The pH response of Au nanodots embodied by phase transfer from oil phase to water phase was also investigated.


Asunto(s)
Oro/química , Sustancias Luminiscentes/química , Ácido Palmítico/química , Polietileneimina/química , Puntos Cuánticos , Concentración de Iones de Hidrógeno , Nanotecnología/métodos , Electricidad Estática
14.
J Nanosci Nanotechnol ; 12(6): 4635-43, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22905510

RESUMEN

The formation of gold particles via reduction of HAuCl4 x 4H2O by ascorbic acid in the presence of ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate and sodium alginate has been studied. The shape of the synthesized particles could be tuned by controlling the reaction conditions. Specifically, the flowerlike gold particles can be synthesized by the present synthetic route. It demonstrates that both the ionic liquid and the sodium alginate play an important role for the formation of the flowerlike particles. The synthesized flowerlike particles show enhanced electroactivity for H2O2.


Asunto(s)
Cristalización/métodos , Oro/química , Imidazoles/química , Líquidos Iónicos/química , Nanoestructuras/química , Nanoestructuras/ultraestructura , Agua/química , Sustancias Macromoleculares/química , Ensayo de Materiales , Conformación Molecular , Oxidación-Reducción , Tamaño de la Partícula , Sales (Química)/química , Soluciones , Propiedades de Superficie
15.
Micromachines (Basel) ; 13(2)2022 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-35208402

RESUMEN

Metal sulfides are considered excellent materials for oxygen evolution reaction because of their excellent conductivity and high electrocatalytic activity. In this report, the NiS-Cu2S composites were prepared on copper foam (NiS-Cu2S-CF) using a facile synthetic strategy. The scanning electron microscopy results confirmed that the NiS nanoneedles were successfully grown on Cu2S nanoflakes, greatly increasing the active sites. Particularly, the optimized 15% NiS-Cu2S-CF composite demonstrated excellent oxygen evolution activity with a small overpotential of 308 mV@20 mA cm-2, which is significantly smaller than that of noble metal-based electrocatalysts and other NiS-Cu2S-CF composites. The enhanced oxygen evolution activity is attributed to the unique morphology that can provide ample active sites, rich ion-transfer pathways, and the synergistic effect between NiS and Cu2S, which can boost the electron transfer rate.

16.
Nat Commun ; 13(1): 4433, 2022 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-35907876

RESUMEN

Kinase-catalyzed phosphorylation plays a crucial role in pathological cardiac hypertrophy. Here, we show that CDC-like kinase 4 (CLK4) is a critical regulator of cardiomyocyte hypertrophy and heart failure. Knockdown of Clk4 leads to pathological cardiomyocyte hypertrophy, while overexpression of Clk4 confers resistance to phenylephrine-induced cardiomyocyte hypertrophy. Cardiac-specific Clk4-knockout mice manifest pathological myocardial hypertrophy with progressive left ventricular systolic dysfunction and heart dilation. Further investigation identifies nexilin (NEXN) as the direct substrate of CLK4, and overexpression of a phosphorylation-mimic mutant of NEXN is sufficient to reverse the hypertrophic growth of cardiomyocytes induced by Clk4 knockdown. Importantly, restoring phosphorylation of NEXN ameliorates myocardial hypertrophy in mice with cardiac-specific Clk4 deletion. We conclude that CLK4 regulates cardiac function through phosphorylation of NEXN, and its deficiency may lead to pathological cardiac hypertrophy. CLK4 is a potential intervention target for the prevention and treatment of heart failure.


Asunto(s)
Cardiomegalia , Insuficiencia Cardíaca , Animales , Cardiomegalia/patología , Modelos Animales de Enfermedad , Insuficiencia Cardíaca/metabolismo , Ratones , Ratones Noqueados , Proteínas de Microfilamentos/metabolismo , Miocitos Cardíacos/metabolismo , Fosforilación , Proteínas Serina-Treonina Quinasas , Proteínas Tirosina Quinasas
17.
Chem Commun (Camb) ; 56(25): 3637-3640, 2020 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-32105284

RESUMEN

A cross-linked π-conjugated polymeric cobalt phthalocyanine material was developed by a facile, economical, scalable, and solid-phase synthesis method. In addition to being highly recyclable, this material showed greatly enhanced activity for the aerobic oxidative coupling of amines compared with a molecular catalyst before heterogenization, indicating good prospects for the material with a π-conjugated electronic character.

18.
Polymers (Basel) ; 12(1)2020 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-31935952

RESUMEN

A new strategy for preparing amphibious ZnO quantum dots (QDs) with blue fluorescence within hyper-branched poly(ethylenimine)s (HPEI) was proposed in this paper. By changing [Zn2+]/[OH-] molar ratio and heating time, ZnO QDs with a quantum yields (QY) of 30% in ethanol were obtained. Benefiting from the amphibious property of HPEI, the ZnO/HPEI nanocomposites in ethanol could be dissolved in chloroform and water, acquiring a QY of 53%, chloroform and 11% in water. By this strategy, the ZnO/HPEI nano-composites could be applied in not only in optoelectronics, but also biomedical fields (such as bio-imaging and gene transfection). The bio-imaging application of water-soluble ZnO/HPEI nanocomposites was investigated and it was found that they could easily be endocytosed by the COS-7 cells, without transfection reagent, and they exhibited excellent biological imaging behavior.

19.
J Nanosci Nanotechnol ; 6(3): 691-7, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16573122

RESUMEN

A simple and efficient route has been employed to deposit noble metal nanoparticles (Pt, Ru, Pt-Ru, Rh, Ru-Sn) onto carbon nanotubes (CNTs) in supercritical methanol solution. In this method, the inorganic metallic salts acted as metal precursors, and methanol as solvent as well as reductant for the precursors. The as-prepared nanocomposites were structurally and morphologically characterized by X-ray diffraction spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy, and X-ray photoelectron spectroscopy analyses. It was demonstrated that the CNTs were decorated by crystalline metal nanoparticles with uniform sizes and a narrow particle size distribution. The size and loading content of the nanoparticles on CNTs could be tuned by manipulating reaction parameters. Furthermore, the formation mechanism of the composites was also discussed.


Asunto(s)
Cristalización/métodos , Metales/química , Nanotecnología/métodos , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestructura , Cromatografía con Fluido Supercrítico/métodos , Ensayo de Materiales , Metanol , Conformación Molecular , Tamaño de la Partícula , Soluciones
20.
J Nanosci Nanotechnol ; 6(1): 175-9, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16573091

RESUMEN

In this work, a simple, fast and efficient route is presented for the metal (such as Pt, Rh, etc.) nanocrystal synthesis and deposition on carbon nanotubes (CNTs) in ionic liquids (ILs) via microwave heating. In this method, inorganic salts (such as H2PtCl6.4H2O, RhCl3.2H2O, etc.) dissolved in ILs, 1,1,3,3-tetramethylguanidinium trifluoroacetate or 1,1,3,3-tetramethylguanidinium lactate, were reduced to metal nanoparticles by glycol with the aid of microwave heating, and the produced metal nanoparticles could be decorated on CNTs in the presence of CNTs in ILs. The resulting nanomaterials were characterized by means of transmission electron microscopy and X-ray diffraction. It was demonstrated that the homogeneously dispersed Pt nanocrystals with the size of 2-3 nm were obtained using H2PtCl6.4H2O as precursor, and they deposited on CNTs with the similar size when CNTs was present in ILs. This technique also can be extended to fabricate other noble metal nanocrystals (including Rh, Au, etc.) and corresponding CNT composites.


Asunto(s)
Carbono/química , Platino (Metal)/química , Cristalografía/métodos , Indicadores y Reactivos , Compuestos Inorgánicos , Microscopía Electrónica , Microondas , Modelos Moleculares , Nanoestructuras/química , Difracción de Rayos X
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