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1.
Angew Chem Int Ed Engl ; : e202407067, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771481

RESUMO

The instability of the solid electrolyte interface (SEI) is a critical challenge for the zinc metal anodes, leading to an erratic electrode/electrolyte interface and hydrogen evolution reaction (HER), ultimately resulting in anode failure. This study uncovers that the fluorine species dissolution is the root cause of SEI instability. To effectively suppress the F- dissolution, an introduction of a low-polarity molecule, 1,4-thioxane (TX), is proposed, which reinforces the stability of the fluorine-rich SEI. Moreover, the TX molecule has a strong affinity for coordinating with Zn2+ and adsorbing at the electrode/electrolyte interface, thereby diminishing the activity of local water and consequently impeding SEI dissolution. The robust fluorine-rich SEI layer promotes the high durability of the zinc anode in repeated plating/stripping cycles, while concurrently suppressing HER and enhancing Coulombic efficiency. Notably, the symmetric cell with TX demonstrates exceptional electrochemical performance, sustaining over 500 hours at 20 mA cm-2 with 10 mAh cm-2. Furthermore, the Zn||KVOH full cell exhibits excellent capacity retention, averaging 6.8 mAh cm-2 with 98 % retention after 400 cycles, even at high loading with a lean electrolyte. This work offers a novel perspective on SEI dissolution as a key factor in anode failure, providing valuable insights for the electrolyte design in energy storage devices.

2.
Org Biomol Chem ; 19(34): 7432-7437, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34397075

RESUMO

A highly efficient cyanosilylation protocol mediated by the easily available n-BuLi with a wide range of aldehydes and ketones was developed. This protocol features excellent yields with very low n-BuLi loadings (0.01-0.05 mol%) at room temperature, solvent-free process, good chemo-/regio-selectivity and functional group tolerance and scalability. A possible reaction pathway based upon stoichiometric reactivity was put forward.

3.
Proc Natl Acad Sci U S A ; 109(15): 5791-6, 2012 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-22454496

RESUMO

Toll-like receptor 3 (TLR3) mediates antiviral response by recognizing double-stranded RNA. Its cytoplasmic domain is tyrosine phosphorylated upon ligand binding and initiates downstream signaling via the adapter TIR-containing adaptor inducing interferon-ß (TRIF). However, the kinase responsible for TLR3 phosphorylation remains unknown. We show here that Bruton's tyrosine kinase (BTK)-deficient macrophages failed to secrete inflammatory cytokines and IFN-ß upon TLR3 stimulation and were impaired in clearing intracellular dengue virus infection. Mutant mice were also less susceptible to d-galactosamine/p(I:C)-induced sepsis. In the absence of BTK, TLR3-induced phosphoinositide 3-kinase (PI3K), AKT and MAPK signaling and activation of NFκB, IRF3, and AP-1 transcription factors were all defective. We demonstrate that BTK directly phosphorylates TLR3 and in particular the critical Tyr759 residue. BTK point mutations that abrogate or led to constitutive kinase activity have opposite effects on TLR3 phosphorylation. Loss of BTK also compromises the formation of the downstream TRIF/receptor-interacting protein 1 (RIP1)/TBK1 complex. Thus, BTK plays a critical role in initiating TLR3 signaling.


Assuntos
Antivirais/imunologia , Vírus da Dengue/imunologia , Proteínas Tirosina Quinases/metabolismo , Receptor 3 Toll-Like/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Tirosina Quinase da Agamaglobulinemia , Animais , Citocinas/biossíntese , Vírus da Dengue/fisiologia , Ativação Enzimática , Proteínas Ativadoras de GTPase/metabolismo , Células HEK293 , Humanos , Interferon beta/biossíntese , Sistema de Sinalização das MAP Quinases , Ativação de Macrófagos , Macrófagos/enzimologia , Macrófagos/virologia , Camundongos , Camundongos Endogâmicos C57BL , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/deficiência , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fatores de Transcrição/metabolismo , Replicação Viral
4.
J Colloid Interface Sci ; 650(Pt A): 169-181, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37399753

RESUMO

Piezocatalytic technology with controllable generation of reactive oxygen species (ROS) is emerging in wastewater treatment. This study employed the synergetic regulation of functional surface and phase interface modification to effectively accelerate redox reaction in piezocatalytic process. We anchored the conductive polydopamine (PDA) onto Bi2WO6 (BWO) using template method, in which a small amount of Bi precipitation to induce partial phase transition of BWO from tetragonal to orthorhombic (t/o) in virtue of simple calcination. ROS traceability studies have identified the synergistic relationship between charge separation and transfer. Polarization in two-phase coexistence is intimately modulated by the orthorhombic relative central cation displacement. The orthorhombic phase with large electric dipole moment significantly promotes the generation of piezoresistive effect of intrinsic tetragonal BWO and optimizes the charge distribution. PDA further overcomes the obstruction of carrier migration at the phases interface to accelerate the generation rate of free radicals. Consequently, the superior rhodamine B (RhB) piezocatalytic degradation rate of 0.10 and 0.32 min-1 were delivered by t/o-BWO and t/o-BWO@PDA, respectively. This work reveals a feasible polarization enhancement strategy for the phase coexistence, and flexibly introduces the in-situ synthesized economical polymer conductive unit into the piezocatalysts.

5.
J Colloid Interface Sci ; 636: 167-175, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36628899

RESUMO

The piezo-/photocatalytic effects of ZnO have been in the limelight because of their great potential in environmental remediation and energy conversion. However, the poor recyclability of the suspended catalysts can cause inevitable secondary pollution, which is one of the major issues that limit the practical application of these materials. To address this problem, a magnetically retrievable Fe3O4@SiO2@ZnO nanocomposite was designed and successfully synthesized by multi-step reactions. The ZnO nanorods were vertically grown on the surface of the magnetic Fe3O4@SiO2 microspheres, while SiO2 served as an insulator to protect the inner core and to inhibit charge transfer across the core/shell interface. The Fe3O4@SiO2@ZnO nanocomposite can be easily collected and separated by using a magnetic field. Along with the good recyclability, the material also exhibited high efficiencies in piezocatalytic, photocatalytic and piezo-photocatalytic dye degradation processes. The rate constant of piezo-photocatalysis reached 95.9 × 10-3 min-1, which was 2.2 and 6.1 times that of the individual piezocatalysis and photocatalysis, respectively. The present result confirmed the existence of a synergetic effect between piezo- and photocatalytic processes. Hereby, we demonstrated that incorporation of a magnetic carrier is a feasible strategy to achieve retrievable and highly efficient piezo-/photocatalyst.

6.
ACS Appl Mater Interfaces ; 14(9): 11375-11387, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35191663

RESUMO

Point defects in piezoelectric semiconductors play a significant role in regulating the piezocatalytic performance. However, the role of metal vacancies in piezocatalysis has been less explored than that of oxygen vacancies. Herein, Bi2WO6 (BWO) nanosheets with tunable Bi defects were synthesized using an ion exchange method. High-resolution transmission electron microscopy directly revealed the existence of Bi vacancies in the lattice of BWO nanosheets and the precipitation of Bi quasiparticles. The BWO nanosheets with the highest concentration of Bi vacancies exhibited an excellent decomposition efficiency (7.83 × 10-2 min-1) over rhodamine B under ultrasound. The phenomenon is mainly attributed to the increased charge carrier concentration as a consequence of defect energy levels. In addition, the significant enhancement of light absorption capacity caused by the surface plasmon resonance effect of quasiparticles indicates that Bi ions escape from the lattice and combine with free electrons around BWO to form Bi quantum dots, which function as electron traps to facilitate the separation of charge carriers during the piezocatalytic process. This work systematically reveals the essential affiliation of metal vacancies and surface metal clusters in piezocatalysts and verifies the significance of vacancy engineering in piezocatalytic application.

7.
ACS Appl Mater Interfaces ; 14(4): 5223-5236, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35067059

RESUMO

Piezocatalysis is one of the green and promising catalytic technologies for the degradation of organic pollutants. Surface modifications such as exposed facet engineering and surface decoration of nanoparticles (NPs) are simple but useful enhancement strategies for a catalytic system. However, the synergistic effect and mechanism of facet engineering and dual-cocatalyst decoration on piezocatalytic activity are still ambiguous and more investigations are expected. Herein, the piezocatalytic activities of BaTiO3 (BTO) polyhedrons with anisotropic {001} and {110} facets and BTO cubes with isotropic {001} facets were compared. Furthermore, BaTiO3 (BTO) convex polyhedrons with selectively deposited Ag NPs and uniformly loaded Co3O4 quantum dots (QDs) are rationally synthesized through photochemical deposition. The individual and synergistic effects of Ag NPs and Co3O4 QDs on the piezocatalytic activities are systematically studied. It was found that dual-cocatalyst-modified BTO possesses the highest piezocatalytic activity in methyl orange degradation, with a reaction constant k of 0.0539 min-1, around 5, 2.2, and 1.3 times higher than that of nonmodified and Ag NP- and Co3O4 QD-modified BTO, respectively. Moreover, dual-cocatalyst-decorated BTO also exhibits excellent piezocatalytic performance in nondye pollutant degradation, with ∼100% tetracycline hydrochloride decomposed in 60 min. By analyzing the contribution, quantifying the amount of different free radicals, and comparing the chemical states of surface elements before and after piezocatalytic measurements, it was inferred that facet-dependent Ag NPs acted as efficient electron-transport sites, while uniformly loaded Co3O4 QDs served as hole-transfer sites to fully facilitate the migration of electrons and holes in a piezocatalytic reaction. This research presents a rational and effectual modification strategy to enhance the piezocatalytic activity of piezocatalysts and gives a thorough discussion of the enhanced mechanism.

8.
J Colloid Interface Sci ; 607(Pt 2): 1589-1602, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34587533

RESUMO

It is of great significance to understand the role of carrier in piezocatalysis of composites by studying the separation mode of carriers under dynamic polarization field. Herein, the separation and migration pathways of carriers under piezoelectric field are investigated by synthesizing heterojunctions with Bi2WO6 (BWO) nanosheets grown vertically on g-C3N4 (CN) coated ZnO nanorods and directly on ZnO. Compared with the photocatalysis, the piezocatalytic efficiency of Rhodamine B (RhB) by BWO/ZnO is significantly increased to 0.121 min-1, which indicated the polarization field promotes band tilt and Z-scheme formation. After introducing the CN interlayer, the piezocatalytic efficiency of BWO/CN/ZnO is further improved (0.217 min-1), which can be attributed to the unique core-shell structure with Z-scheme heterojunctions. This unique structure provides more active sites and excited carrier concentration, the intermediate layer CN also reduces the direct contact and recombination of electrons and holes controlled by polarization potential at the interface between BWO and ZnO. This work deeply analyzes the influence of carrier concentration, separation efficiency and transport process on piezocatalysis, which provides a reference for the design of efficient catalysts.


Assuntos
Poluentes Ambientais , Óxido de Zinco , Catálise , Luz
9.
Nanoscale Adv ; 3(11): 3159-3166, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36133656

RESUMO

Developing new techniques that can synthesize one-dimensional piezoelectric materials on a large scale is of great significance for boosting piezocatalytic applications. In this work, we proposed a high-efficiency template hydrothermal method for large-scale synthesis of piezoelectric Na0.5Bi0.5TiO3 (NBT) nanowires. By ion-exchange with Bi3+, Na2Ti3O7 template nanowires can be easily and entirely transformed to NBT. The piezocatalytic activity of the NBT nanowires was thoroughly investigated with respect to their capability to degrade typical organic pollutants, including Rhodamine B, methylene blue, methyl orange, tetracycline hydrochloride, phenol, and bisphenol A. The NBT nanowires exhibited the highest efficiency in piezocatalytic degradation of Rhodamine B, which was completely decomposed within 80 min (rate constant ∼0.0575 min-1). The electron spin resonance spin-trapping technique and active species capture experiments were employed to characterize free radicals. The present work is advantageous for the high yield of NBT nanowires and the excellent piezocatalytic performance. The reported template hydrothermal method can potentially be extended to the synthesis of other perovskite nanowires.

10.
ACS Appl Mater Interfaces ; 12(12): 14005-14015, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32142247

RESUMO

Powder-form piezocatalysts suffer from poor recyclability and pose a potential threat of creating serious secondary pollution, which restrict their practical applications. Thin-film piezocatalysts, which not only exhibit good recyclability but also fully contact with solution, are believed to be one of the solutions to address these problems. In this work, the nanostructured BaTiO3 (BTO) thin films were fabricated by a facile hydrothermal method for their potential applications in piezocatalysis. The vertically standing BTO nanosheets grown on the top of TiO2 nanorod arrays exhibited superior piezocatalytic performance as well as piezo-electrochemical property. Given the different strain states between thin-film piezocatalyst and powder-form piezocatalyst, both the impact force of water and isostatic pressure are taken into consideration in finite element method (FEM) simulation. The FEM simulation shows that a stronger piezoelectric filed can be built in BTO nanosheets because of their easier deformation, and thus can lead to a higher piezocatalytic degradation efficiency. Our work presented here is expected to provide a potential route for the nanoengineering of thin-film piezocatalysts and clarify the catalytic mechanism for substrate-fixed piezocatalysts.

11.
ACS Omega ; 4(4): 6775-6783, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31459799

RESUMO

Herein, we present a facile method for deoxygenative hydroboration of a broad range of carboxylic acids under very mild conditions. The most striking feature of this attractive hydroboration is that this elusive and challenging transformation was realized without catalyst and solvent. The investigation of solvent effect showed that tetrahydrofuran was also suitable for this kind of reaction. Moreover, a successful gram-scale trial may provide a very promising toolkit for carboxylic acid reduction at a large scale.

12.
Nanoscale ; 11(44): 21128-21136, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31682250

RESUMO

A variety of nanostructured Bi4Ti3O12 materials with diverse morphologies were synthesized by a novel hydrothermal method using layered titanate Na2Ti3O7 as a synthetic precursor. Among these materials, decussated nanoplates exhibit superior piezocatalytic activity compared with other piezocatalysts of the perovskite family. The enhanced piezocatalytic activity is attributed to the large piezoelectric potential difference and the short distance between polar surfaces, which may help enhance the driving force of charge transport. The finite element method (FEM) simulation of piezoelectric response in different Bi4Ti3O12 nanostructures was performed to illustrate the influence of morphological features on the piezocatalytic performance. The catalytic mechanism of Bi4Ti3O12 was investigated by the detection and characterization of free radicals and intermediate products with electron spin resonance (ESR) spin-trapping technique and liquid chromatography-mass spectrometry (LC-MS). This work may push forward the development of piezocatalytic materials, and provide insights into piezocatalysis for environmental applications.

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