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1.
Macromol Rapid Commun ; : e2400563, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39292819

RESUMO

Nanorods as building blocks are promising to construct functional superstructures. A paramagnetic Fe3O4-based composite nanorod is large-scale synthesized from the poly(2-vinylpyridine) (P2VP) side chain grafted polymer bottlebrush by electrostatics-mediated intramolecular crosslinking via metallic coordination. Ultrasonication-assisted fracturing of the composite nanorod derives the corresponding A2-type composite nanorods whose two ends are active with the metallic coordinated P2VP exposed. The active ends are prone to connection upon feeding ligands (acidic or alkaline) or metallic ions to trigger the organization of the A2-type nanorods toward functional superstructures. Their microstructure is tunable from linear nanowires to branches, which is dependent on the valent state of the assistant chemicals. The report method is easily extended to derive a family of A2-type active nanorods with varied compositions and functions which are capable to organize functional nanomaterials with tunable microstructure.

2.
Macromol Rapid Commun ; : e2400393, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39292765

RESUMO

Polymer single-chain nanoparticles (SCNPs) have found a wide range of applications spanning catalysts, sensors and nanomedicine. The generation of structured SCNPs from star-shaped polymers with diverse architectures and functionalities affords a new avenue to expand the emerging research area. The large-scale synthesis of structured SCNPs is described by the electrostatics-mediated intramolecular crosslinking of three types of 3-armed star-shaped polymers (T-P4VP, T-PS-b-P4VP, and T-P4VP-b-PS), whose configuration is tunable from spherical to cage-shaped to dumbbell-shaped and star-shaped. The structured SCNPs are amphiphilic and can be used as solid surfactants to stabilize different types of emulsions.

3.
Angew Chem Int Ed Engl ; : e202413502, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136325

RESUMO

Garnet Li7La3Zr2O12 (LLZO)-based solid-state electrolytes (SSEs) hold promise for realizing next-generation lithium metal batteries with high energy density. However, the high stiffness of high-temperature sintered LLZO makes it brittle and susceptible to strain during the fabrication of solid-state batteries. Cold-pressed LLZO exhibits improved ductility but suffers from insufficient Li+ conductivity. Here, we report cold-pressed Ta-doped LLZO (Ta-LZ) particles integrated with ductile Li6PS5Cl (LPSC) via a Li+ conductive Li-containing Ta-Cl structure. This configuration creates a continuous Li+ conduction network by enhancing the Li+ exchange at the Ta-LZ/LPSC interface. The resulting Ta-LZ/LPSC SSE exhibits Li+ conductivity of 4.42 × 10-4 S cm-1 and a low activation energy of 0.31 eV. Li symmetric cells with Ta-LZ/LPSC SSE demonstrate excellent Li dendrite suppression ability, with an improved critical current density of 5.0 mA cm-2 and a prolonged cycle life exceeding 600 h at 1 mA cm-2. Our finding provides valuable insights into developing cold-pressed ceramic powder electrolytes for high-performance all-solid-state batteries.

4.
J Am Chem Soc ; 145(4): 2404-2413, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36656650

RESUMO

Constructing precisely oriented assemblies and exploring their orientation-dependent properties remain a challenge for Janus nanoparticles (JNPs) due to their asymmetric characteristics. Herein, we propose a bubble-driven instant quasi-1D interfacial strategy for the oriented assembly of JNP chains in a highly controllable manner. It is found that the rapid formation of templated bubbles can promote the interfacial orientation of JNPs kinetically, while the confined quasi-1D interface in the curved liquid bridge can constrain the disordered rotation of the particles, yielding well-oriented JNP chains in a long range. During the evaporation process, the interfacial orientation of the JNPs can be transferred to the assembled chains. By regulating the amphiphilicity of the JNPs, both heteraxial and coaxial JNP assemblies are obtained, which show different polarization dependences on light scattering, and the related colorimetric logic behaviors are demonstrated. This work demonstrates the great potential of patterned interfacial assembly with a manageable orientation and shows the broad prospect of asymmetric JNP assembly in constructing novel optoelectronic devices.

5.
Soft Matter ; 19(9): 1705-1708, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36786895

RESUMO

We have proposed an approach to achieve nanofibers or composite nanofibers with functional nanoparticles via the protrusion of the budding interfacial membrane in an oil-water emulsion droplet stabilized with copolymers. The nanofibers were formed by the wrapping of the monolayer of the copolymers. The length is tunable with the copolymer concentration and water/oil ratio of the emulsion.

6.
Macromol Rapid Commun ; 44(20): e2300280, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37335979

RESUMO

Janus composite particles (JPs) with distinct compartmentalization of varied components thus performances and anisotropic shape display a variety of properties and have demonstrated great potentials in diversify practical applications. Especially, the catalytic JPs are advantageous for multi-phase catalysis with much easier separation of products and recycling the catalysts. In the first section of this review, typical methods to synthesize the JPs with varied morphologies are briefly surveyed in the category of polymeric, inorganic and polymer/inorganic composite. In the main section, recent progresses of the JPs in emulsion interfacial catalysis are summarized covering organic synthesis, hydrogenation, dye degradation, and environmental chemistry. The review will end by calling more efforts toward precision synthesis of catalytic JPs at large scale to meet the stringent requirements in practical applications such as catalytic diagnosis and therapy by the functional JPs.


Assuntos
Emulsões , Emulsões/química , Catálise , Hidrogenação
7.
Nano Lett ; 22(13): 5530-5537, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35771509

RESUMO

Epitaxial growth is a powerful tool for synthesizing heterostructures and integrating multiple functionalities. However, interfacial mixing can readily occur and significantly modify the properties of layered structures, particularly for those containing energy storage materials with smaller cations. Here, we show a two-step sequence involving the growth of an epitaxial LiCoO2 cathode layer followed by the deposition of a binary transition metal oxide. Orientation-controlled epitaxial synthesis of the model solid-state-electrolyte Li2WO4 and anode material Li4Ti5O12 occurs as WO3 and TiO2 nucleate and react with Li ions from the underlying cathode. We demonstrate that this lithiation-assisted epitaxy approach can be used for energy materials discovery and exploring different combinations of epitaxial interfaces that can serve as well-defined model systems for mechanistic studies of energy storage and conversion processes.

8.
Small ; 18(3): e2104213, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34816590

RESUMO

Multiferroics with simultaneous electric and magnetic orderings are highly desirable for sensing, actuation, data storage, and bio-inspired systems, yet developing flexible materials with robust multiferroic properties at room temperature is a long-term challenge. Utilizing water-soluble Sr3 Al2 O6 as a sacrificial layer, the authors have successfully self-assembled a freestanding BaTiO3 -CoFe2 O4 heteroepitaxial nanostructure via pulse laser deposition, and confirmed its epitaxial growth in both out-of-plane and in-plane directions, with highly ordered CoFe2 O4 nanopillars embedded in a single crystalline BaTiO3 matrix free of substrate constraint. The freestanding nanostructure enjoys super flexibility and mechanical integrity, not only capable of spontaneously curving into a roll, but can also be bent with a radius as small as 4.23 µm. Moreover, piezoelectricity and ferromagnetism are demonstrated at both microscopic and macroscopic scales, confirming its robust multiferroicity at room temperature. This work establishes an effective route for flexible multiferroic materials, which have the potential for various practical applications.


Assuntos
Nanoestruturas , Compostos de Bário/química , Nanoestruturas/química , Temperatura , Titânio/química
9.
Langmuir ; 38(37): 11406-11413, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36084177

RESUMO

Cross-linked epoxy resin (EP) single-hole Janus hollow spheres are prepared by cross-linking induced phase separation within an emulsion droplet and selective modification. The droplet is composed of an EP oligomer, toluene, and hexadecane. 2-Ethyl-4-methylimidazole is used as the cross-linker added to the aqueous phase. During the cross-linking, hexadecane forms an eccentric core in the cross-linked EP sphere. A single hole forms across the shell after dissolving the solvents, and a single-hole hollow sphere is achieved. The hole and cavity size are controlled by adjusting the solvent content and cross-linker concentration. Furthermore, frozen wax is used as the core material instead of hexadecane to effectively protect the sphere's interior surface. Selective modification of the exterior and interior surfaces is thus permitted. As an example, a responsive single-hole Janus hollow sphere is prepared by the favorable growth of a silica-polyoxyethylene composite layer onto the exterior surface and a selective grafting of poly(2-diethylaminoethyl methacrylate) (PDEAEMA) by atom-transfer radical polymerization (ATRP) onto the interior. The Janus sphere is water-dispersible and controllably captures and releases oil from the aqueous environment as triggered by the pH value.

10.
Macromol Rapid Commun ; 43(8): e2200016, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35218095

RESUMO

A zwitterionic polymeric hair-coated stainless steel mesh membrane is fabricated, which demonstrates efficient separation of oil/water mixtures and emulsions. The hairy coating of poly(divinylbenzene-co-vinylbenzene chloride) is generated by precipitation cationic polymerization, and subsequently grafting a zwitterionic polymer layer by atom transfer radical polymerization of sulfobetaine methacrylate. The microstructure of the hairy coating is tunable from an array of individual nanofibers to porous networks by interweaving of the hairs. The long-range attraction of zwitterionic polymers with water renders the coated mesh with excellent superhydrophilic and underwater superoleophobic performance. The coated mesh is highly antifouling to avoid the prehydration in conventional methods. Moreover, the microstructure is demonstrated to be responsible for the high separation efficiency of oil/water emulsion. Therefore, separation of oil/water mixtures and emulsions becomes easier by the coated mesh, which is promising in industrial oil field sewage treatment.

11.
Macromol Rapid Commun ; 43(17): e2200157, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35503683

RESUMO

For double network (DN) hydrogels, their performance can be tuned by adjusting the interaction between their two networks. A novel DN hydrogel toughening approach is proposed by employing Janus nanoparticles (JNs) as crosslinkers to gain a conjoined-network hydrogel. First, a kind of JNs modified by amino groups and quaternary ammonium salt is synthesized, named R3 N+ -JN-NH2 . The DN hydrogel is fabricated based on ionic coordination between calcium chloride (CaCl2 ) and sodium alginate (Alg), as well as covalent (benzoic imine) between glycol chitosan (GC) and benzaldehyde-capped poly(ethylene oxide) (BzCHO-PEO-BzCHO). Based on the same covalent and ionic dynamic crosslinking mechanism, the added R3 N+ -JN-NH2 interacts with two networks to promote crosslinking to form a dually crosslinked structure. The R3 N+ -JN-NH2 effectively provides more energy dissipation, and the hydrogel with conjoined networks shows better compression resistance.


Assuntos
Hidrogéis , Nanopartículas Multifuncionais , Alginatos/química , Hidrogéis/química , Polietilenoglicóis/química
12.
Angew Chem Int Ed Engl ; 61(27): e202205183, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35470952

RESUMO

We report the large-scale synthesis of photoluminescent single-chain nanoparticles (SCNPs) by electrostatic-mediated intramolecular crosslinking in a concentrated solution of 40 mg mL-1 by continuous addition of the free radical initiator. Poly(vinyl benzyl chloride) was charged by quaternization with vinyl-imidazolium for the intramolecular crosslinking by using 2,2-dimethoxy-2-phenylacetophenone (DMAP) as the radical initiator. Under the electrostatic repulsion thus interchain isolation, the intrachain crosslinking experiences the transition from coil through pearl-necklace to globular state. The SCNPs demonstrate strong photoluminescence in the visible range when the non-emissive units are confined thereby. Composition and microstructure of the SCNPs are tunable. The photoluminescent tadpole-like Janus SCNP can be used to selectively illuminate interfacial membranes while stabilizing the emulsions.

13.
J Am Chem Soc ; 143(23): 8538-8542, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34076411

RESUMO

Due to the intrinsically plentiful Sn vacancies, developing n-type SnTe thermoelectric materials is a big challenge. Herein, n-type SnTe thermoelectric materials with remarkable performance were successfully synthesized through suppressing Sn vacancies, followed by electron-doping. Pb alloying notably depressed the Sn vacancies via populating Sn vacancies in SnTe (supported by transmission electron microscopy), and the electrical transports were shifted from p-type to n-type through introducing electrons using I doping. In the n-type SnTe, we found that the electrical conductivity could be enhanced by increased carrier mobility through sharpening conduction bands after alloying Pb, while the lattice thermal conductivity could be reduced via strong phonon scattering after introducing defects by Pb alloying and I doping. Resulting from these enhancements, the n-type Sn0.6Pb0.4Te0.98I0.02 achieves a notably high ZTmax ∼ 0.8 at 573 K and a remarkable ZTave ∼ 0.51 at 300-823 K, which can match many excellent p-type SnTe. This work indicates that n-type SnTe could be experimentally acquired and is a promising candidate for thermoelectric generation, which will stimulate further research on n-type SnTe thermoelectric materials and even devices on the basis of both n- and p-type SnTe legs.

14.
Soft Matter ; 17(7): 1796-1801, 2021 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-33399612

RESUMO

Core/shell PVSt-b-PS@Fe3O4 composite nanoparticles (NPs) are achieved by grafting living cationic block copolymer chains onto the surface of amine-capped Fe3O4 NPs via fast termination. The number of chains grafted can be tuned via the molecular weight of PVSt-b-PS. Upon grafting PEG onto the PVSt block via a click reaction, the resulting (PVSt-g-PEG)-b-PS@Fe3O4 composite NPs become highly dispersible in water. A composite nanoparticle with ten chains is selected as a homogeneous NP to demonstrate the dynamic stepwise organization of the NP as oil is fed into the aqueous dispersion. The individual NPs with captured oil are further aggregated, but remain stable with increasing oil content. Eventually, a Pickering emulsion forms in which the aggregates are anchored at the emulsion interface. This dynamic behavior study helps to provide an understanding of the mechanism by which NPs stabilize Pickering emulsions.

15.
Nano Lett ; 20(12): 8584-8591, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33200603

RESUMO

Graphene on SiO2 enables fabrication of Si-technology-compatible devices, but a transfer of these devices from other substrates and direct growth have severe limitations due to a relatively small grain size or device-contamination. Here, we show an efficient, transfer-free way to integrate centimeter-scale, single-crystal graphene, of a quality suitable for electronic devices, on an insulating SiO2 film. Starting with single-crystal graphene grown epitaxially on Ru(0001), a SiO2 film is grown under the graphene by stepwise intercalation of silicon and oxygen. Thin (∼1 nm) crystalline or thicker (∼2 nm) amorphous SiO2 has been produced. The insulating nature of the thick amorphous SiO2 is verified by transport measurements. The device-quality of the corresponding graphene was confirmed by the observation of Shubnikov-de Haas oscillations, an integer quantum Hall effect, and a weak antilocalization effect within in situ fabricated Hall bar devices. This work provides a reliable platform for applications of large-scale, high-quality graphene in electronics.

16.
J Infect Dis ; 221(11): 1775-1781, 2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-32179908

RESUMO

BACKGROUND: Previous studies on the pneumonia outbreak caused by the 2019 novel coronavirus disease (COVID-19) were mainly based on information from adult populations. Limited data are available for children with COVID-19, especially for infected infants. METHODS: We report a 55-day-old case with COVID-19 confirmed in China and describe the identification, diagnosis, clinical course, and treatment of the patient, including the disease progression from day 7 to day 11 of illness. RESULTS: This case highlights that children with COVID-19 can also present with multiple organ damage and rapid disease changes. CONCLUSIONS: When managing such infant patients with COVID-19, frequent and careful clinical monitoring is essential.


Assuntos
Infecções por Coronavirus/complicações , Infecções por Coronavirus/diagnóstico , Traumatismos Cardíacos/etiologia , Fígado/lesões , Pneumonia Viral/complicações , Pneumonia Viral/diagnóstico , Pneumonia/etiologia , Betacoronavirus , COVID-19 , China , Infecções por Coronavirus/patologia , Infecções por Coronavirus/terapia , Progressão da Doença , Feminino , Humanos , Lactente , Pandemias , Pneumonia Viral/patologia , Pneumonia Viral/terapia , SARS-CoV-2 , Resultado do Tratamento
17.
Macromol Rapid Commun ; 41(19): e2000392, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32833324

RESUMO

A strategy is proposed to stabilize the polymeric interface by using the irregular Janus nanosheet (JNS). The poly(vinylidene fluoride) (PVDF)/poly(l-lactic acid) (PLLA) at 60/40 (wt/wt) with a bi-continuous structure is selected as the model melt blend, and the PMMA/epoxy JNS is synthesized and used as the compatibilizer. The JNS is preferentially located at the interface. The interfacial coverage by the JNS reaches a saturated state forming the interconnected jamming structure at 0.5 wt% of the JNS. The interface is thus stabilized which is well preserved after annealing at high temperature. After selectively etching PLLA, the robust PVDF porous material is derived with the JNS armored at the pore skeleton surface. The porous material provides a universal scaffold to achieve stable functional materials after filling the pores.


Assuntos
Materiais Biocompatíveis , Polímeros , Porosidade
18.
Nano Lett ; 19(11): 8311-8317, 2019 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-31644875

RESUMO

Artificial complex-oxide heterostructures containing ultrathin buried layers grown along the pseudocubic [111] direction have been predicted to host a plethora of exotic quantum states arising from the graphene-like lattice geometry and the interplay between strong electronic correlations and band topology. To date, however, electronic-structural investigations of such atomic layers remain an immense challenge due to the shortcomings of conventional surface-sensitive probes with typical information depths of a few angstroms. Here, we use a combination of bulk-sensitive soft X-ray angle-resolved photoelectron spectroscopy (SX-ARPES), hard X-ray photoelectron spectroscopy (HAXPES), and state-of-the-art first-principles calculations to demonstrate a direct and robust method for extracting momentum-resolved and angle-integrated valence-band electronic structure of an ultrathin buckled graphene-like layer of NdNiO3 confined between two 4-unit cell-thick layers of insulating LaAlO3. The momentum-resolved dispersion of the buried Ni d states near the Fermi level obtained via SX-ARPES is in excellent agreement with the first-principles calculations and establishes the realization of an antiferro-orbital order in this artificial lattice. The HAXPES measurements reveal the presence of a valence-band bandgap of 265 meV. Our findings open a promising avenue for designing and investigating quantum states of matter with exotic order and topology in a few buried layers.

19.
Angew Chem Int Ed Engl ; 59(24): 9365-9369, 2020 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-32090438

RESUMO

Molecular-surfactant-stabilized emulsions are susceptible to coalescence and Ostwald ripening. Amphiphilic particles, which have a much stronger anchoring strength at the interface, could effectively alleviate these problems to form stable Pickering emulsions. Herein, we describe a versatile method to fabricate biocompatible amphiphilic dimer particles through controlled coprecipitation and phase separation. The dimer particles consist of a hydrophobic PLA bulb and a hydrophilic shellac-PEG bulb, thus resembling nonionic molecular surfactants. The size and diameter ratio of the dimer particles are readily tunable, providing flexible control over the water/oil interfacial curvature and thus the type of emulsion. The particle-stabilized emulsions were stable for a long period of time and could be destabilized through a pH-triggered response. The biocompatible amphiphilic dimer particles with tunable morphology and functionality are thus ideal colloidal surfactants for various applications.


Assuntos
Materiais Biocompatíveis/química , Tensoativos/química , Coloides , Dimerização , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Poliésteres/química , Polietilenoglicóis/química
20.
Langmuir ; 35(18): 6032-6038, 2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-30983356

RESUMO

We report a method to prepare polymer/inorganic Janus particles by transferring self-assembled membranes of copolymers such as PS- b-PAA at an emulsion interface when the amine-capped particles such as paramagnetic Fe3O4@SiO2 core/shell particles are preferentially adsorbed by specific interactions. While the particles are protected, the exposed side can be further modified to conjugate aldehyde-capped polyethylene oxide (PEO). Both connections become robust by covalent bonds. The hydrophilic PEO and hydrophobic PS chains are distinctly compartmentalized onto the opposite sides of the Fe3O4@SiO2 particles. As a magnetic responsive solid surfactant, the stabilized emulsions can be driven with a magnet for directional movement and coalescence with increasing magnetic strength. This method can be extended to other Janus particles with tunable organic materials and solid particles.

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