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1.
Front Oncol ; 12: 944487, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36059616

RESUMO

Circulating tumor cells (CTCs) that survive in the blood are playing an important role in the metastasis process of tumor. In addition, they have become a tool for tumor diagnosis, prognosis and recurrence monitoring. CTCs can exist in the blood as individual cells or as clumps of aggregated cells. In recent years, more and more studies have shown that clustered CTCs have stronger metastasis ability compared to single CTCs. With the deepening of studies, scholars have found that cancer cells can combine not only with each other, but also with non-tumor cells present in the blood, such as neutrophils, platelets, etc. At the same time, it was confirmed that non-tumor cells bound to CTCs maintain the survival and proliferation of cancer cells through a variety of ways, thus promoting the occurrence and development of tumor. In this review, we collected information on tumorigenesis induced by CTC clusters to make a summary and a discussion about them. Although CTC clusters have recently been considered as a key role in the transition process, many characteristics of them remain to be deeply explored. A detailed understanding of their vulnerability can prospectively pave the way for new inhibitors for metastasis.

2.
Eur J Pharmacol ; 931: 175226, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36007607

RESUMO

Metastasis is the leading cause of death in melanoma patients. Aerobic glycolysis is a common metabolic feature in tumor and is closely related to cell growth and metastasis. Kaempferol (KAM) is one of the active ingredients in the total flavonoids of Chinese traditional medicine Sparganii Rhizoma. Studies have shown that it interferes with the cell cycle, apoptosis, angiogenesis and metastasis of tumor cells, but whether it can affect the aerobic glycolysis of melanoma is still unclear. Here, we explored the effects and mechanisms of KAM on melanoma metastasis and aerobic glycolysis. KAM inhibited the migration and invasion of A375 and B16F10 cells, and reduced the lung metastasis of melanoma cells. Extracellular acidification rates (ECAR) and glucose consumption were obviously suppressed by KAM, as well as the production of ATP, pyruvate and lactate. Mechanistically, the activity of hexokinase (HK), the first key kinase of aerobic glycolysis, was significantly inhibited by KAM. Although the total protein expression of HK2 was not significantly changed, the binding of HK2 and voltage-dependent anion channel 1 (VDAC1) on mitochondria was inhibited by KAM through AKT/GSK-3ß signal pathway. In conclusion, KAM inhibits melanoma metastasis via blocking aerobic glycolysis of melanoma cells, in which the binding of HK2 and VDAC1 on mitochondria was broken.


Assuntos
Melanoma , Canal de Ânion 1 Dependente de Voltagem , Linhagem Celular Tumoral , Proliferação de Células , Glicogênio Sintase Quinase 3 beta/metabolismo , Glicólise , Hexoquinase/metabolismo , Humanos , Quempferóis/farmacologia , Melanoma/patologia , Mitocôndrias/metabolismo , Canal de Ânion 1 Dependente de Voltagem/metabolismo
3.
Small ; 18(33): e2203422, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35871552

RESUMO

In heterogeneous catalysis, metal particle morphology and size can influence markedly the activity. It is of great significance to rationally design and control the synthesis of Pt at the atomic level to demonstrate the structure-activity relationship toward electrocatalysis. Herein, a powerful strategy is reported to synthesize graphene-supported platinum-based electrocatalyst, that is, nanocatalysts with controllable size can be prepared by iced photochemical method, including single atoms (Pt-SA@HG), nanoclusters (Pt-Clu@HG), and nanocrystalline (Pt-Nc@HG). The Pt-SA@HG exhibits unexpected electrocatalytic hydrogen evolution reaction (HER) performances with 13 mV overpotential at 10 mA cm-2 current densities which surpass Pt-Clu@HG and Pt-Nc@HG. The in situ X-ray absorption fine structure spectroscopy (XAFS) and density functional theory (DFT) calculations determine the Pt-C3 active site is linchpin to the excellent HER performance of Pt-SA@HG. Compared with the traditional Pt-Nx coordination structure, the pure carbon coordinated Pt-C3 site is more favorable for HER. This work opens up a new way to adjust the metal particle size and catalytic performance of graphene at a multiscale level.


Assuntos
Grafite , Catálise , Grafite/química , Hidrogênio , Gelo , Platina
5.
Adv Mater ; 34(36): e2205678, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35853459

RESUMO

High mass loading and high areal capacity are key metrics for commercial batteries, which are usually limited by the large charge-transfer impedance in thick electrodes. This can be kinetically deteriorated under low temperatures, and the realization of high-areal-capacity batteries in cold climates remains challenging. Herein, a low-temperature high-areal-capacity rechargeable potassium-tellurium (K-Te) battery is successfully fabricated by knocking down the kinetic barriers in the cathode and pairing it with stable anode. Specifically, the in situ electrochemical self-reconstruction of amorphous Cu1.4 Te in a thick electrode is realized simply by coating micro-sized Te on the Cu collector, significantly improving its ionic conductivity. Meanwhile, the optimized electrolyte enables fast ion transportation and a stable K-metal anode at a large current density and areal capacity. Consequently, this K-Te battery achieves a high areal capacity of 1.25 mAh cm-2 at -40 °C, which greatly exceeds those of most reported works. This work highlights the significance of electrode design and electrolyte engineering for high areal capacity at low temperatures, and represents a critical step toward practical applications of low-temperature batteries.

6.
Plant J ; 111(4): 1015-1031, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35699670

RESUMO

Bud dormancy helps woody perennials survive winter and activate robust plant development in the spring. For apple (Malus × domestica), short-term chilling induces bud dormancy in autumn, then prolonged chilling leads to dormancy release and a shift to a quiescent state in winter, with subsequent warm periods promoting bud break in spring. Epigenetic regulation contributes to seasonal responses such as vernalization. However, how histone modifications integrate seasonal cues and internal signals during bud dormancy in woody perennials remains largely unknown. Here, we show that H3K4me3 plays a key role in establishing permissive chromatin states during bud dormancy and bud break in apple. The global changes in gene expression strongly correlated with changes in H3K4me3, but not H3K27me3. High expression of DORMANCY-ASSOCIATED MADS-box (DAM) genes, key regulators of dormancy, in autumn was associated with high H3K4me3 levels. In addition, known DAM/SHORT VEGETATIVE PHASE (SVP) target genes significantly overlapped with H3K4me3-modified genes as bud dormancy progressed. These data suggest that H3K4me3 contributes to the central dormancy circuit, consisting of DAM/SVP and abscisic acid (ABA), in autumn. In winter, the lower expression and H3K4me3 levels at DAMs and gibberellin metabolism genes control chilling-induced release of dormancy. Warming conditions in spring facilitate the expression of genes related to phytohormones, the cell cycle, and cell wall modification by increasing H3K4me3 toward bud break. Our study also revealed that activation of auxin and repression of ABA sensitivity in spring are conditioned at least partly through temperature-mediated epigenetic regulation in winter.


Assuntos
Malus , Ácido Abscísico/metabolismo , Cromatina/metabolismo , Epigênese Genética , Regulação da Expressão Gênica de Plantas , Histonas , Malus/metabolismo , Dormência de Plantas/genética
7.
Micromachines (Basel) ; 13(5)2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35630219

RESUMO

Elastic materials include metal plates, rubber, foam, airbags and so on, which have a good buffer effect, toughness and strong recovery ability. In this paper, the deformation and thermal diffusion of 2D and 3D thin plates are studied. Two models are established for the deformation of 2D thin plates. The bending deformation equation of rectangular and circular plates is derived, and the semi-analytical solution of the deflection function w(x,y) is found through the Fourier series approximation in the polar coordinate. The consistencies of the numerical solution and the theoretical solution are verified by numerical method. Then, we find that the factors affecting the deformation are related to the Young's modulus, load, plate length and deformation factor α of the material. In a separate temperature physics field, we establish a heat conduction model of 2D graphene film. Three numerical schemes of the transient heat conduction equation of FDM-FEM are given. In contrast, this paper uses the implicit Euler method to discrete the time term. Furthermore, we compared the difference between the adiabatic condition and the convection condition by the graphical method and the curve trend. The results show that the temperature near the adiabatic boundary is higher. Finally, we proposed a 3D dynamic thermal-mechanical coupling model (3D-DTMCM) that has been established. A laser heating monocrystalline silicon sheet with periodic motion formula is given. The temperature radiation of the laser heat source has Gaussian distribution characteristics. Our proposed model can dynamically determine Young's modulus with a variable temperature. The numerical results show that the higher the temperature is, the higher the strain energy density of the plate is. In addition, the deformation amplitude of the plates in the coupling field is larger than that in the single mechanical field. Finally, we also discussed the stress field distribution of mixed cracks under high temperature and high load. Our research provides theoretical support for the deformation of different plates, and also reflects the value of the coupled model in practical applications.

8.
Chemosphere ; 299: 134375, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35314181

RESUMO

As some of the most promising alternatives to traditional non-degradable materials, photodegradable materials have advantages of environmental benignity and rapid degradation under simple conditions. In this work, nontoxic TiO2 and cost-effective g-C3N4 have been compounded in a weight of 9:1 to form a photocatalytic additive with high activity. A 25 wt% loading of this photocatalytic additive has been incorporated into the polyacrylonitrile (PAN) by centrifugal electrospinning to prepare an abiotic degradable PAN material. Our results showed that the PAN chain could be almost fully degraded within 90 h in an aqueous medium under simulated sunlight in the absence of microorganisms. Product analysis implied that degradation of the PAN chain mainly involved the breaking of -CN and C-C bonds by radicals, followed by oxidation of terminal groups to carboxyl and gradual mineralization to CO2 and H2O. This design strategy may provide new insight for the production and degradation mechanism of photodegradable polymer.


Assuntos
Iluminação , Luz Solar , Resinas Acrílicas , Catálise , Titânio
9.
Chemosphere ; 299: 134464, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35358552

RESUMO

It is of great significance for improving electron transmission performance by changing of the outer ring structure of iron phthalocyanine. Herein, 4 (pyridine-2, 3-yl) iron phthalocyanine (FepyPc), as N-rich pyridyl-iron phthalocyanine derivative, was introduced to degrade pharmaceutical contaminants. The catalytic degradation of organic pollutants with FepyPc was studied by activating peroxymonosulfate (PMS) at room temperature. The results clarified that the removal rate of carbamazepine (CBZ) was close to 100% within 60 min and the calculated apparent rate constant was about 2 times larger than FePc, which proved that FepyPc had superior performance. Four active species were identified for the degradation of CBZ, including superoxide radical (•O2-), singlet oxygen (1O2), sulfate radical (SO4•-) and hydroxyl radical (•OH). In addition, the possible reaction mechanism was inferred in FepyPc/PMS/sunlight system for CBZ removal. Finally, the CBZ degradation pathway was proposed by using ultra-performance liquid chromatography and high definition mass spectrometry (UPLC/HDMS). This research provided a meaningful and efficient method for the elimination of pharmaceutical contaminants.


Assuntos
Resíduos de Drogas , Indóis , Peróxidos , Luz Solar , Carbamazepina , Resíduos de Drogas/química , Compostos Ferrosos , Indóis/química , Peróxidos/química
10.
Nat Commun ; 13(1): 1322, 2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35277523

RESUMO

Copper-based materials can reliably convert carbon dioxide into multi-carbon products but they suffer from poor activity and product selectivity. The atomic structure-activity relationship of electrocatalysts for the selectivity is controversial due to the lacking of systemic multiple dimensions for operando condition study. Herein, we synthesized high-performance CO2RR catalyst comprising of CuO clusters supported on N-doped carbon nanosheets, which exhibited high C2+ products Faradaic efficiency of 73% including decent ethanol selectivity of 51% with a partial current density of 14.4 mA/cm-2 at -1.1 V vs. RHE. We evidenced catalyst restructuring and tracked the variation of the active states under reaction conditions, presenting the atomic structure-activity relationship of this catalyst. Operando XAS, XANES simulations and Quasi-in-situ XPS analyses identified a reversible potential-dependent transformation from dispersed CuO clusters to Cu2-CuN3 clusters which are the optimal sites. This cluster can't exist without the applied potential. The N-doping dispersed the reduced Cun clusters uniformly and maintained excellent stability and high activity with adjusting the charge distribution between the Cu atoms and N-doped carbon interface. By combining Operando FTIR and DFT calculations, it was recognized that the Cu2-CuN3 clusters displayed charge-asymmetric sites which were intensified by CH3* adsorbing, beneficial to the formation of the high-efficiency asymmetric ethanol.

12.
Proc Natl Acad Sci U S A ; 119(8)2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35165185

RESUMO

Developing heterogeneous catalysts with atomically dispersed active sites is vital to boost peroxymonosulfate (PMS) activation for Fenton-like activity, but how to controllably adjust the electronic configuration of metal centers to further improve the activation kinetics still remains a great challenge. Herein, we report a systematic investigation into heteroatom-doped engineering for tuning the electronic structure of Cu-N4 sites by integrating electron-deficient boron (B) or electron-rich phosphorus (P) heteroatoms into carbon substrate for PMS activation. The electron-depleted Cu-N4/C-B is found to exhibit the most active oxidation capacity among the prepared Cu-N4 single-atom catalysts, which is at the top rankings of the Cu-based catalysts and is superior to most of the state-of-the-art heterogeneous Fenton-like catalysts. Conversely, the electron-enriched Cu-N4/C-P induces a decrease in PMS activation. Both experimental results and theoretical simulations unravel that the long-range interaction with B atoms decreases the electronic density of Cu active sites and down-shifts the d-band center, and thereby optimizes the adsorption energy for PMS activation. This study provides an approach to finely control the electronic structure of Cu-N4 sites at the atomic level and is expected to guide the design of smart Fenton-like catalysts.

13.
Exp Hematol Oncol ; 11(1): 2, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35057866

RESUMO

BACKGROUND: Tanshinone II A is an effective component extracted from Salvia miltiorrhiza and the roles of Tanshinone IIA in regulating the stemness of tumor cells remain unclear. This work aims to explore the roles and underlying mechanisms of Tanshinone IIA in breast cancer stemness. METHODS: In vitro mammary spheroid formation, flow cytometry assay on CD24-/CD44+ sub-population, ALDH activity detection, cell viability assay and western blot analysis, and in vivo tumor-initiating analysis were performed to examine the effects of Tanshinone IIA on the stemness of breast cancer cells. MiRNAs-based transcriptome sequencing and data analysis, online dataset analysis, luciferase reporter assay combined with rescuing experiments were constructed to explore the underlying mechanisms. RESULTS: Tanshinone IIA attenuated the stemness of breast cancer cells, evident by downregulating the expression of stemness markers, hindering the capacity of spheroid formation, decreasing the CD24-/CD44+ sub-population in a concentration-dependent manner and reducing the tumor-initiating ability of breast cancer cells. Additionally, Tanshinone IIA enhanced adriamycin sensitivity and attenuated adriamycin resistance of breast cancer cells. Combined with miRNAs-based transcriptome sequencing assay, it was found that Tanshinone IIA downregulated miR-125b level and upregulated its target gene STARD13 (StAR-related lipid transfer protein 13) level, thus inactivating the miR-125b/STARD13 axis, which had been previously confirmed to promote breast cancer progression. Notably, miR-125b overexpression enhanced the stemness of breast cancer cells, and miR-125b overexpression or STARD13 knockdown impaired the inhibitory effects of Tanshinone IIA on the stemness of breast cancer cells. CONCLUSIONS: Tanshinone IIA could attenuate the stemness of breast cancer cells via targeting the miR-125b/STARD13 axis.

14.
Curr Mol Pharmacol ; 15(3): 487-501, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34382521

RESUMO

Hypoxia, a common feature of malignant tumours, is mainly caused by insufficient oxygen supply. Hypoxia is closely associated with cancer development, affecting cancer invasion, metastasis, energy metabolism, and other pathological processes, and is not conducive to cancer treatment and prognosis. Tumour cells exacerbate metabolic abnormalities to adapt to the hypoxic microenvironment, especially to enhance aerobic glycolysis. Glycolysis leads to an acidic microenvironment in cancer tissues, enhancing cancer metastasis, deterioration, and drug resistance. Therefore, hypoxia is a therapeutic target that cannot be ignored in cancer treatment. The adaptation of tumour cells to hypoxia is mainly regulated by hypoxia-inducible factors (HIFs), and the stability of HIFs is improved under hypoxic conditions. HIFs can promote glycolysis in tumours by regulating glycolytic enzymes, transporters, and the TCA cycle. In addition, HIFs indirectly affect glycolysis by interacting with non- coding RNAs. Therefore, targeting hypoxia and HIFs is important for tumour therapy.


Assuntos
Neoplasias , Hipóxia Celular/fisiologia , Metabolismo Energético , Glicólise/fisiologia , Humanos , Hipóxia , Neoplasias/metabolismo , Microambiente Tumoral
15.
Environ Technol ; 43(17): 2569-2580, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33576725

RESUMO

The current environmental problems urgently require researchers to seek an environmentally friendly, effective and easy to operate sewage treatment method. Graphite carbon nitride (g-C3N4), which has the advantages of simple preparation, safety, non-toxicity and chemical resistance, was expected to become a photocatalyst for solving environmental pollution. However, the performances of g-C3N4 still have some limitations that the electron hole recombination is fast and the powder is not easy to recover. In this study, zinc-doped graphite carbon nitride photocatalyst (Zn-g-C3N4) was mixed with polyacrylonitrile (PAN) to produce photocatalyst fibres by electrospinning. It not only solves the problem that the powder catalyst is difficult to recycle, but also effectively inhibits the recombination of photoelectron-hole pairs. Zn-g-C3N4/PAN has good photocatalytic activity for the simultaneous reduction of hexavalent chromium and degradation of pharmaceuticals. When organic pollutants are present, the reduction efficiency of hexavalent chromium was improved without affecting its own removal efficiency. The potential application value of Zn-g-C3N4/PAN catalytic fibre was further explored by simulating the complex actual water environment. The composite fibre can be easily reused and keep its superior photocatalytic performance. The mechanism of pharmaceuticals degradation was proposed, in which ∙O2- is the most important active species, which leads to the oxidation of pharmaceuticals. Besides, the photoelectrons generated by the catalyst can reduce the toxic hexavalent chromium. The efficiency of Zn-g-C3N4 to remove pollutants is improved by PAN fibre as a carrier, which not only solves the problem of difficult recovery of powder catalysts, but also provides more active sites.


Assuntos
Poluentes Ambientais , Grafite , Catálise , Cromo , Grafite/química , Compostos de Nitrogênio , Compostos Orgânicos , Pós , Zinco
16.
Small ; 18(13): e2105883, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34918467

RESUMO

Atomically dispersed metal sites (ADMSs) attract immense attention because they can be used in the fields of energy and environmental protection as they are characterized by high atomic utilization efficiency and exhibit high activity. Various supports for anchoring isolated metal atoms are developed to construct ADMSs characterized by highly stable and well-defined structures. This can be achieved by increasing the number of anchoring sites and reinforcing metal-support interactions. MXenes, a new series of 2D nanomaterials, exhibit promising potential in stabilizing isolated metal atoms because of their large specific surface areas and unique surface properties. The high conductivity and hydrophilicity of MXenes can be attributed to the nature of surface functionalization and the properties of tunable structures of the materials. Benefiting from these excellent properties, MXenes can find their applications in various fields. Herein, the precise characterization methods that can be followed to study ADMSs, the construction of MXene-supported ADMSs using theoretical predictions, and experimental modulation strategies are summarized, and their corresponding applications in electrocatalysis, organocatalysis, and advanced battery systems are systematically illustrated. It is hoped that this review will provide insights that can be used for the further development of MXene-supported ADMSs.

17.
Chem Sci ; 12(45): 15045-15053, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34909144

RESUMO

Hydrogen peroxide (H2O2) plays essential roles in various physiological and pathological processes. The electrochemical hydrogen peroxide reduction reaction (HPRR) has been recognized as an efficient approach to H2O2 sensing; however, the HPRR has always suffered from low tolerance against the oxygen reduction reaction (ORR), resulting in poor selectivity of the HPRR-based sensing platform. In this study, we find that the electrochemical HPRR occurs preferentially compared to the ORR when isolated Cu atoms anchored on carbon nitride (Cu1/C3N4) are used as a single-atom electrocatalyst, which is theoretically attributed to the lower energy barrier of the HPRR than that of the ORR on a Cu1/C3N4 single-atom catalyst (SAC). With the Cu1/C3N4 SAC as the electrocatalyst, we fabricated microsensors that have a good response to H2O2, but not to O2 or other electroactive neurochemicals. When implanted into a living rat brain, the microsensor shows excellent in vivo sensing performance, enabling its application in real-time quantitative investigation of the dynamics of H2O2 production induced by mercaptosuccinate and glutathione monoethyl ester in a living animal brain.

18.
Oxid Med Cell Longev ; 2021: 7037786, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34804370

RESUMO

Pathological angiogenesis, as exhibited by aberrant vascular structure and function, has been well deemed to be a hallmark of cancer and various ischemic diseases. Therefore, strategies to normalize vasculature are of potential therapeutic interest in these diseases. Recently, identifying bioactive compounds from medicinal plant extracts to reverse abnormal vasculature has been gaining increasing attention. Tanshinone IIA (Tan IIA), an active component of Salvia miltiorrhiza, has been shown to play significant roles in improving blood circulation and delaying tumor progression. However, the underlying mechanisms responsible for the therapeutic effects of Tan IIA are not fully understood. Herein, we established animal models of HT-29 human colon cancer xenograft and hind limb ischemia to investigate the role of Tan IIA in regulating abnormal vasculature. Interestingly, our results demonstrated that Tan IIA could significantly promote the blood flow, alleviate the hypoxia, improve the muscle quality, and ameliorate the pathological damage after ischemic insult. Meanwhile, we also revealed that Tan IIA promoted the integrity of vascular structure, reduced vascular leakage, and attenuated the hypoxia in HT-29 tumors. Moreover, the circulating angiopoietin 2 (Ang2), which is extremely high in these two pathological states, was substantially depleted in the presence of Tan IIA. Also, the activation of Tie2 was potentiated by Tan IIA, resulting in decreased vascular permeability and elevated vascular integrity. Mechanistically, we uncovered that Tan IIA maintained vascular stability by targeting the Ang2-Tie2-AKT-MLCK cascade. Collectively, our data suggest that Tan IIA normalizes vessels in tumors and ischemic injury via regulating the Ang2/Tie2 signaling pathway.


Assuntos
Abietanos/farmacologia , Neoplasias do Colo/irrigação sanguínea , Regulação da Expressão Gênica/efeitos dos fármacos , Isquemia/tratamento farmacológico , Neovascularização Patológica/prevenção & controle , Receptor TIE-2/antagonistas & inibidores , Proteínas de Transporte Vesicular/antagonistas & inibidores , Inibidores da Angiogênese/farmacologia , Animais , Antineoplásicos Fitogênicos/farmacologia , Apoptose , Proliferação de Células , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Humanos , Isquemia/metabolismo , Isquemia/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
19.
ACS Appl Mater Interfaces ; 13(45): 54096-54105, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34749501

RESUMO

Aqueous zinc-ion batteries (ZIBs) are regarded as a promising candidate for ultrafast charge storage owing to the high ionic conductivity of aqueous electrolytes and high theoretical capacity of zinc metal anodes. However, the strong electrostatic interaction between high-charge-density zinc ions and host materials generally leads to sluggish ion-transport kinetics and structural collapse of rigid cathode materials during the charge/discharge process, so searching for suitable cathode materials for ultrafast and long-term stable ZIBs remains a great challenge. Herein, flexible electron-rich ion channels enabling fast-charging and stable aqueous ZIBs have been demonstrated. Because of the nitrogen-rich conjugated structure of organic phenazine (PNZ) molecules, electron-rich ion channels are formed with the C═N redox centers situated on the channel surface, where zinc ions can transport rapidly and react with active moieties directly. Meanwhile, the π-conjugated systems and inherent flexibility of PNZ molecules can accommodate rapid strain changes and maintain their structural stability during zinc-ion intercalation/deintercalation. Consequently, they exhibit a high capacity of 94.2 mAh g-1 at an ultrahigh rate of 700C (208.6 A g-1) and an ultralong life over 100,000 cycles at 100C, which are superior to those of previously reported aqueous ZIBs. Our work presents a new way for developing ultrafast and ultrastable aqueous ZIBs.

20.
ACS Appl Mater Interfaces ; 13(45): 53683-53690, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34726386

RESUMO

1,2-Dichloroethane (1,2-DCE) is a toxic volatile organic compound, which is harmful to the environment and human health. Herein, we develop a single-atom Ru catalyst anchored on the mesoporous schistose γ-Al2O3 (Ru SACs/m-γ-Al2O3) to enhance the catalytic activity and selectivity toward 1,2-DCE degradation. The Ru SACs/m-γ-Al2O3 shows low T50 and T90 (the temperature for 50 and 90% conversion) of 215 and 289 °C, which are lower than those for Ru NPs/m-γ-Al2O3 (291 and 374 °C) and pristine m-γ-Al2O3 (323 and 386 °C). The degradation products are mainly CO2 (>94%) and HCl (>90%) by using the Ru SACs/m-γ-Al2O3 catalyst, and almost no byproducts are detected. Furthermore, Ru SACs/m-γ-Al2O3 also presents excellent anti-chlorine poisoning effect and water resistance during the stability test. This work may shed light on the development of efficient single-atom catalysts for the degradation of industrial pollutants.

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