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1.
Chem Soc Rev ; 53(4): 1823-1869, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38192222

RESUMO

Two-dimensional polymers (2DPs) are a class of 2D crystalline polymer materials with definite structures, which have outstanding physical-chemical and electronic properties. They cleverly link organic building units through strong covalent bonds and can construct functional 2DPs through reasonable design and selection of different monomer units to meet various application requirements. As promising energy materials, 2DPs have developed rapidly in recent years. This review first introduces the basic overview of 2DPs, such as their historical development, inherent 2D characteristics and diversified topological advantages, followed by the summary of the typical 2DP synthesis methods recently (including "top-down" and "bottom-up" methods). The latest research progress in assembly and processing of 2DPs and the energy-related applications in energy storage and conversion are also discussed. Finally, we summarize and prospect the current research status, existing challenges, and future research directions of 2DPs.

2.
Chem Commun (Camb) ; 59(43): 6475-6494, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37185628

RESUMO

Three-dimensional graphene (3DG)/metal-organic framework (MOF)-based composites have attracted more and more attention in the field of energy due to their unique hierarchical porous structure and properties. The combination of graphene with MOFs can not only effectively overcome the limitations of poor electrical conductivity and low stability of MOFs, but also prevent the aggregation and reaccumulation between graphene sheets. Moreover, 3DG/MOF composites can also be used as multifunctional precursors with adjustable structures and composition of derivatives, thus expanding their applications in the field of electrochemistry. This feature article elaborates the latest synthesis methods of 3DG/MOF composites and their derivatives, along with their applications in batteries, supercapacitors (SCs) and electrocatalysis. In addition, the current challenges and future prospects of 3DG/MOF-based composites are discussed.

3.
Nanomaterials (Basel) ; 12(16)2022 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-36014741

RESUMO

Hollow nanoboxes structure have raised great attention as microwave absorption materials on account of their ultralow density and large specific area. By introducing an adjustable interior cavity structure, the dielectric loss and microwave absorption performance were affected by the tunable complex permittivity and impedance matching was improved. In our study, hollow CoS2 nanoboxes with designable interspaces were successfully fabricated based on the surfactant-assisted solution method and followed by an in situ ion-exchange process. The structure, elemental compositions and morphology of the products were characterized by XRD, XPS, EDX, SEM and TEM, respectively. In addition, microwave absorption performance and the intrinsic mechanism are investigated in-depth. The paraffin-based composites with 20 wt.% filling contents exhibited superior microwave absorption capacities in view of both maximum reflection loss value (RLmax, -54.48 dB) and effective absorption bandwidth (EAB, below -10 dB, 6.0 GHz), which can be ascribed to unique hollow structure and good impedance matching. With these considerations in mind, this study provides a reference for the construction of high-performance microwave absorbers with unique hollow structure.

4.
Bioengineered ; 12(1): 7694-7703, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34608825

RESUMO

The aim of this study was to explore the effects and action mechanism of Zhike Pingchuan Granule in human bronchial epithelial cells induced by IL-6 or the supernatant of M2. Upon IL-6 stimulation at different doses, Cell Counting Kit-8 (CCK8) assay and flow cytometry were, respectively, utilized to detect the cell viability and apoptosis levels of 16-HBE cells. ELISA and Western blot were, respectively, used to analyze the inflammatory markers and JAK2/STAT3 signals. Immunofluorescence assay was performed to identify M0 and M2 cells. As shown in results, ZKPC perturbed the expression of IL-6 inducible genes important for apoptosis, oxidative and inflammatory response, which was enhanced by JAK2 inhibitor. Besides the inhibitory effects on the phosphorylation levels of JAK2/STAT3, ZKPC markedly increased cell viability and reduced apoptosis in human bronchial epithelial cells (16-HBE) cultured in the supernatant of M2 cells. Collectively, ZKPC could inhibit the IL-6-induced JAK/STAT3 signaling cascade, increase cell viability and decrease apoptosis induced by the supernatant of M2. A more comprehensive understanding of the action mechanism of ZKPC on JAK2/STAT3 signaling pathway in human bronchial epithelial cells induced by IL-6 or M2 supernatant will enable ZKPC development in the control of asthma.


Assuntos
Apoptose/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Células Epiteliais/efeitos dos fármacos , Interleucina-6/metabolismo , Macrófagos/efeitos dos fármacos , Brônquios/citologia , Sobrevivência Celular , Células Cultivadas , Humanos , Pirrolidinas , Mucosa Respiratória/citologia , Sulfonamidas
5.
Front Pharmacol ; 12: 707967, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34504425

RESUMO

Background: Anti-programmed cell death protein 1 (PD-1) has been successfully used in carcinomas treatment. However, it causes significant adverse effects (AEs), including cutaneous reactions, particularly the life-threatening severe bullous skin reactions (SBSR) and toxic epidermal necrolysis (TEN). Case summary: Herein, we described for the first time a case report of SBSR induced by anti-PD-1 therapy in a cervical cancer patient. In addition, we revised existing literature on anti-PD-1 induced cutaneous reactions. We reported a cervical cancer patient who was treated with four successive cycles of Sintilimab and Toripalimab injections and developed systemic rashes, bullae, and epidermal desquamation, which worsened and led to infection, eventually causing death after being unresponsive to aggressive treatments. Conclusion: Anti-PD-1 antibodies commonly cause skin toxicity effects, some of which may be deadly. Therefore, healthcare providers should observe early symptoms and administer proper treatment to prevent aggravation of symptoms.

6.
Exp Ther Med ; 22(2): 899, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34257712

RESUMO

The present study aimed to investigate the effects of zhike pingchuan granules (ZKPC) on bronchial asthma and the underlying mechanism. A bronchial asthma mouse model was established by aerosol inhalation of ovalbumin. The changes in lung pathomorphology were observed by hematoxylin and eosin staining. The levels of IL-1ß, TNF-α and IL-6 in bronchoalveolar lavage fluid (BALF) and serum were detected by corresponding ELISA kits. Levels of reactive oxygen species, malondialdehyde and superoxide dismutase in lung tissues were analyzed using corresponding kits. The expression of proteins related to apoptosis and the IL-6/janus kinase 2 (JAK2)/STAT3 pathway was detected by western blot analysis. The results showed that ZKPC significantly restored the dry/wet ratio and alleviated lung pathomorphology of bronchial asthmatic mice. In addition, ZKPC inhibits inflammation, oxidative stress levels and cell apoptosis in bronchial asthmatic mice and also suppressed the IL-6/JAK2/STAT3 pathway. Fedratinib (a JAK2 inhibitor) further strengthened the alleviative effects of ZKPC on bronchial asthma. In conclusion, ZKPC improved bronchial asthma by suppressing the IL-6/JAK2/STAT3 pathway.

7.
Chem Asian J ; 14(23): 4315-4321, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31631572

RESUMO

Exploring advanced electrocatalysts for electrocatalytic hydrogen evolution is highly desired but remains a challenge due to the lack of an efficient preparation method and reasonable structural design. Herein, we deliberately designed novel Ag/WO3-x heterostructures through a supercritical CO2 -assisted exfoliation-oxidation route and the subsequent loading of Ag nanoparticles. The ultrathin and oxygen vacancies-enriched WO3-x nanosheets are ideal substrates for loading Ag nanoparticles, which can largely increase the active site density and improve electron transport. Besides, the resultant WO3-x nanosheets with porous structure can form during the electrochemical cycling process induced by an electric field. As a result, the exquisite Ag/WO3-x heterostructures show an enhanced hydrogen evolution reaction (HER) activity with a low onset overpotential of ≈30 mV, a small Tafel slope of ≈40 mV dec-1 at 10 mA cm-2 , and as well as long-term durability. This work sheds light on material design and preparation, and even opens up an avenue for the development of high-efficiency electrocatalysts.

8.
Chem Commun (Camb) ; 55(88): 13307-13310, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31626252

RESUMO

In this work, Au nanoparticles (NPs) grown on defective WO3-x (Au/WO3-x) show superior electrocatalytic N2 reduction activity under ambient conditions in 0.1 M KOH. At -0.2 V versus the reversible hydrogen electrode (vs. RHE), the Au/WO3-x catalyst achieves a large NH3 yield of 23.15 µg h-1 mg-1 and a high faradaic efficiency (FE) of 14.72%. Further density functional theory (DFT) calculations indicate that electron transfer between the Au nanoparticles and defective WO3-x promotes the activation of N2 molecules effectively.

9.
Chem Asian J ; 12(23): 2980-2984, 2017 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-28885770

RESUMO

Two-dimensional (2D) semiconductors have recently emerged as a remarkable class of plasmonic alternative to conventional noble metals. However, tuning of their plasmonic resonances towards different wavelengths in the visible-light region with physical or chemical methods still remains challenging. In this work, we design a simple room-temperature chemical reaction route to synthesize amorphous molybdenum oxide (MoO3-x ) nanodots that exhibit strong localized surface plasmon resonances (LSPR) in the visible and near-infrared region. Moreover, tunable plasmon resonances can be achieved in a wide range with the changing surrounding solvent, and accordingly the photoelectrocatalytic activity can be optimized with the varying LSPR peaks. This work boosts the light-matter interaction at the nanoscale and could enable photodetectors, sensors, and photovoltaic devices in the future.

10.
ACS Nano ; 10(2): 2903-9, 2016 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-26840941

RESUMO

Molybdenum disulfide (MoS2) is a promising non-precious-metal catalyst, but its performance is limited by the density of active sites and poor electrical transport. Its metallic 1T phase possesses higher photoelectrocatalytic activity. Thus, how to efficiently increase the concentration of the 1T phase in the exfoliated two-dimensiaonal (2D) MoS2 nanosheets is an important premise. In this work, we propose a strategy to prepare a 2D heterostructure of MoS2 nanosheets using supercritical CO2-induced phase engineering to form metallic 1T-MoS2. Theoretical calculations and experimental results demonstrate that the introduced CO2 in the 2H-MoS2 host can prompt the transformation of partial 2H-MoS2 lattices into 1T-MoS2. Moreover, the electrical coupling and synergistic effect between 2H and 1T phases can greatly facilitate the efficient electron transfer from the active sites of MoS2, which significantly improves the photocatalytic performance.

11.
ACS Appl Mater Interfaces ; 6(16): 14644-52, 2014 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-25100439

RESUMO

In this work, three-dimensional (3D) hierarchical MoS2/polyaniline (PANI) nanoflowers were successfully fabricated via a simple hydrothermal method. The crystal structure and morphology of the MoS2/PANI nanoflowers were characterized by SEM, TEM, XRD, XPS, and FT-IR spectra, revealing that the nanoflowers were composed of ultrathin nanoplates which consisted of few-layered MoS2 nanosheets with enlarged interlayer distance of the (002) plane and PANI. The excellent electrochemical performance of the 3D hierarchical MoS2/PANI nanoflowers was demonstrated. Further 3D hierarchical MoS2/C nanoflowers can be prepared conveniently by annealing the MoS2/PANI sample in a N2 atmosphere at 500 °C for 4 h. The obtained MoS2/C sample exhibited more excellent electrochemical performance due to its excellent electronic conductivity resulting from the close integration of MoS2 nanosheets with carbon matrix. High reversible capacity of 888.1 mAh g(-1) with the Coulombic efficiency maintained at above 90% from the first cycle were achieved at a current density of 100 mA g(-1). Even at a current density of 1000 mA g(-1), the reversible capacity of the MoS2/C sample could be retained at 511 mAh g(-1). The excellent electrochemical performance of these two samples could be attributed to the combined action of enlarged interlayer distance of the ultrathin MoS2 nanosheets, 3D architectures, hierarchical structures, and conductive material. Thus, these 3D hierarchical nanoflowers are competent as promising anode materials for high-performance lithium-ion batteries.

12.
ACS Appl Mater Interfaces ; 6(12): 9689-97, 2014 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-24882146

RESUMO

Functionalized porous carbon materials with hierarchical structure and developed porosity coming from natural and renewable biomass have been attracting tremendous attention recently. In this work, we present a facile and scalable method to synthesize MnO2 loaded carbonaceous aerogel (MnO2@CA) composites via the hydrothermal carbonaceous (HTC) process. We employ two reaction systems of the mixed metal ion precursors to study the optimal selective adsorption and further reaction of MnO2 precursor on CA. Our experimental results show that the system containing KMnO4 and Na2S2O3·5H2O exhibits better electrochemical properties compared with the reaction system of MnSO4·H2O and (NH4)2S2O8. For the former, the obtained MnO2@CA displays the specific capacitance of 123.5 F·g(-1). The enhanced supercapacitance of MnO2@CA nanocomposites could be ascribed to both electrochemical contributions of the loaded MnO2 nanoparticles and the porous structure of three-dimensional carbonaceous aerogels. This study not only indicates that it is vital for the reaction systems to match with porous carbonaceous materials, but also offers a new fabrication strategy to prepare lightweight and high-performance materials that can be used in energy storage devices.


Assuntos
Capacitância Elétrica , Fontes de Energia Elétrica , Compostos de Manganês/química , Nanopartículas/química , Óxidos/química , Adsorção , Biomassa , Carbono/química , Eletroquímica , Porosidade
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