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1.
Clin Transl Med ; 13(6): e1300, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37337470

RESUMO

BACKGROUND: Ferroptosis is an important iron-dependent form of cell death in hepatocellular carcinoma (HCC). Sorafenib, a potent ferroptosis inducer, is used to treat advanced HCC but its efficacy is limited by the development of drug resistance. METHODS: The effects of DUXAP8 expression on HCC progression were evaluated by TCGA database, Kaplan-Meier analysis, and in situ hybridization analysis. Sorafenib resistant HCC cell lines were modeled in vitro to study the regulation of DUXAP8 on ferroptosis in HCC induced by sorafenib. We used RNA pull-down, immunofluorescence assays, acyl-biotinyl exchange assay and mass spectrometry analysis to assess the molecular mechanism of ferroptosis regulation by DUXAP8. Syngeneic subcutaneous and orthotopic CDX models were used to assess whether DUXAP8 inhibition improves HCC in vivo. RESULTS: LncRNA DUXAP8, which is highly expressed in liver cancer and associated with poor prognosis, contributes to sorafenib resistance through suppression of ferroptosis. In vitro tests revealed that DUXAP8 reduced the sensitivity of HCC to sorafenib-induced ferroptosis by acting on SLC7A11, a subunit of the amino acid antiporter system xc-. DUXAP8 facilitates SLC7A11 palmitoylation and impedes its lysosomal degradation, thereby enhancing SLC7A11 action and suppressing ferroptosis. RNA pull-down and immunofluorescence assays confirmed that DUXAP8 decreased membrane translocation and promoted sorting of de-palmitoylated SLC7A11 to lysosomes by binding of DUXAP8 to SLC7A11. In addition, mass spectrometric analysis found that the Cys414 residue of SLC7A11 might be the predominant mutant site responsible for molecular masking of SLC7A11 lysosomal sorting. Further, the antitumor effect of DUXAP8 knockdown was verified in orthotopic and subcutaneous CDX models. CONCLUSIONS: Our findings suggest that a novel translational strategy combining sorafenib with DUXAP8 silencing to overcome drug resistance may improve treatment efficacy in patients with advanced HCC.


Assuntos
Carcinoma Hepatocelular , Ferroptose , Neoplasias Hepáticas , RNA Longo não Codificante , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Sorafenibe/farmacologia , Sorafenibe/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , RNA Longo não Codificante/metabolismo , Ferroptose/genética , Lipoilação , Sistema y+ de Transporte de Aminoácidos/genética , Sistema y+ de Transporte de Aminoácidos/metabolismo
2.
Carbohydr Polym ; 316: 121075, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37321751

RESUMO

Aqueous zinc-ion batteries (AZIBs), with the merits of high safety, environmental friendliness, abundant resources, and competitive energy density are recognized as a promising secondary battery technology and are anticipated to be a great alternative to organic lithium-ion batteries (LIBs). However, the commercial application of AZIBs is severely hindered by intractable issues, including high desolvation barrier, sluggish ion transport kinetics, growth of zinc dendrite, and side reactions. Nowadays, cellulosic materials are frequently employed in the fabrication of advanced AZIBs, because of the intrinsically excellent hydrophilicity, strong mechanical strength, sufficient active groups, and unexhaustible production. In this paper, we start from reviewing the success and dilemma of organic LIBs, followed by introducing the next-generation power source of AZIBs. After summarizing the features of cellulose with great potential in advanced AZIBs, we comprehensively and logically analyze the applications and superiorities of cellulosic materials in AZIBs electrodes, separators, electrolytes, and binders with an in-depth perspective. Finally, a clear outlook is delivered for future development of cellulose in AZIBs. Hopefully, this review can offer a smooth avenue for future direction of AZIBs by means of cellulosic material design and structure optimization.


Assuntos
Celulose , Zinco , Íons , Fontes de Energia Elétrica , Eletrodos , Lítio
3.
J Hepatocell Carcinoma ; 10: 483-495, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37007211

RESUMO

Purpose: The current study aimed to evaluate the synergistic efficacy of lenvatinib and FOLFOX (infusional fluorouracil (FU), folinic acid, and oxaliplatin) in hepatocellular carcinoma (HCC) using patient-derived xenograft (PDX) and PDX-derived organotypic spheroid (XDOTS) models in vivo and in vitro. Methods: PDX and matched XDOTS models originating from three patients with HCC were established. All models were divided into four groups and treated with drugs alone or in combination. Tumor growth in the PDX models was measured and recorded, and angiogenesis and phosphorylation of the vascular endothelial growth factor receptor (VEGFR2), rearranged during transfection (RET), and extracellular signal-regulated kinase (ERK) were detected using immunohistochemistry and Western blot assays. The proliferative ability of XDOTS was evaluated through active staining and immunofluorescence staining, and the effect of the combined medication was evaluated using the Celltiter-Glo luminescent cell viability assay. Results: Three PDX models with genetic characteristics similar to those of the original tumors were successfully established. Combining lenvatinib with FOLFOX led to a higher tumor growth inhibition rate than individual therapies (P < 0.01). Immunohistochemical analysis demonstrated that the combined treatment significantly inhibited the proliferation and angiogenesis of PDX tissues (P < 0.05), and Western blot analysis showed that the combined treatment significantly inhibited the phosphorylation of VEGFR2, RET, and ERK compared with single-agent treatment. Additionally, all three matched XDOTS models were successfully cultured with satisfactory activity and proliferation, and the combined therapies led to better suppression of XDOTS growth compared with individual therapy (P < 0.05). Conclusion: Lenvatinib combined with FOLFOX had a synergistic antitumor effect in HCC PDX and XDOTS models by inhibiting the phosphorylation of VEGFR, RET, and ERK.

4.
Environ Technol ; 44(23): 3504-3517, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35389329

RESUMO

Masses of iron sludge generated from engineering practice of classic Fenton reaction constraints its further promotion. Accelerating the FeIII/FeII cycle may be conducive to reducing the initial ferrous slat dosage and the final iron sludge. Based on the reduction of Pd/MIL-100(Fe)-activated hydrogen, an improved Fenton system named MHACF-MIL-100(Fe) was developed at ambient temperature and pressure. 97.8% of sulfamethazine, the target pollutant in this work, could be degraded in 5 min under the conditions of 20 mM H2O2, 25 µM ferrous chloride, initial pH 3.0, 2 g·L-1 composite catalyst Pd/MIL-100(Fe) and hydrogen gas 60 mL·min-1. Combining density functional theory (DFT) calculation and intermediate detection, the degradation of this antibiotic was inferred to start from the cleavage of N-S bond. The catalytic of Pd/MIL-100(Fe), demonstrated by the removal efficiency of SMT and the catalyst morphology, remained intact after six reaction cycles. The present study provides an insight into the promotion of Fenton reaction.


Assuntos
Compostos Férricos , Sulfametazina , Peróxido de Hidrogênio/química , Esgotos , Ferro/química , Compostos Ferrosos , Oxirredução
5.
J Transl Med ; 20(1): 520, 2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36348351

RESUMO

BACKGROUND: The tumour microenvironment and cirrhotic liver are excellent sources of cancer-associated fibroblasts (CAFs), which participate in carcinogenesis. Thus, it is important to clarify the crosstalk between CAFs and HCC cells and the related mechanism in regulating carcinogenesis. METHODS: Human hepatocellular carcinoma (HCC) tissues and matched adjacent normal tissues were obtained from HCC patients. Immunohistochemistry, Western blotting (WB) and RT-qPCR were performed to detect the expression of SCUBE1. The roles of SCUBE1 in inducing stemness features in HCC cells were explored and investigated in vitro and in vivo. Student's t tests or Mann-Whitney U tests were used to compare continuous variables, while chi-square tests or Fisher's exact tests were used to compare categorical variables between two groups. RESULTS: SCUBE1 was confirmed to be highly expressed in CAFs in HCC and had a strong connection with stemness and a poor prognosis. In addition, CAFs were found to secrete SCUBE1 to enhance the malignancy of HCC cells and increase the proportion of CD133-positive cells. Silencing SCUBE1 expression had the opposite effect. The Shh pathway was activated by SCUBE1 stimulation. Inhibition of cyclopamine partially reversed the stimulating effect of SCUBE1 both in vivo and in vitro. Moreover, based on the RT-qPCR, ELISA and WB results, a high SCUBE1 expression level was found in HCC tissue and serum. CONCLUSION: This study revealed that CAFs-derived SCUBE1 can enhance the malignancy and stemness of HCC cells through the Shh pathway. This study aims to provide new perspectives for future HCC studies and provide new strategies for HCC treatment.


Assuntos
Fibroblastos Associados a Câncer , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Proteínas de Ligação ao Cálcio/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Carcinogênese/patologia , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proteínas Hedgehog , Neoplasias Hepáticas/patologia , Microambiente Tumoral , Proteína GLI1 em Dedos de Zinco/genética , Células-Tronco Neoplásicas
6.
Front Nutr ; 9: 899137, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35923199

RESUMO

Background: Observational studies have revealed that dried fruit intake may be associated with cancer incidence; however, confounding factors make the results prone to be disturbed. Therefore, we conducted a two-sample Mendelian randomization (MR) study to explore the causal relationship between dried fruit intake and 11 site-specific cancers. Materials and methods: Forty-three single nucleoside polymers (SNPs) with robust genome-wide association study (GWAS) evidence, strongly correlated with dried fruit intake, were used as instrumental variables (IVs) in this study. The summary-level genetic datasets of site-specific cancers were obtained from the Oncoarray oral cavity and oropharyngeal cancer consortium, International Lung Cancer Consortium, Breast Cancer Association Consortium (BCAC), Ovarian Cancer Association Consortium, PanScan1, and GWAS of other scholars. We analyzed the causality between dried fruit intake and 11 site-specific cancers using the inverse-variance-weighted (IVW) and weighted median (WM) methods. For the results of the MR analysis, Cochran's Q test was used to check for heterogeneity, and multiplicative random effects were used to evaluate the heterogeneity further. Gene pleiotropy was tested using MR-Egger regression and MR-PRESSO methods. In addition, the main results of this study were validated by using the summary statistical data from the FinnGen and UK Biobank databases, and adjusted body mass index (BMI), years of education, fresh fruit intake, and vitamin C using multivariable MR analysis to ensure the stability of the research results. Results: The evidence from IVW analyses showed that each increase of dried fruit intake by one standard deviation was statistically significantly associated with 82.68% decrease of oral cavity/pharyngeal cancer incidence risk (P = 0.0131), 67.01% decrease of lung cancer incidence risk (P = 0.0011), 77% decrease of squamous cell lung cancer incidence risk (P = 0.0026), 53.07% decrease of breast cancer incidence risk (P = 4.62 × 10-5), 39.72% decrease of ovarian cancer incidence risk (P = 0.0183), 97.26% decrease of pancreatic cancer incidence risk (P = 0.0280), 0.53% decrease of cervical cancer incidence risk (P = 0.0482); however, there was no significant effect on lung adenocarcinoma (P = 0.4343), endometrial cancer (P = 0.8742), thyroid cancer (P = 0.6352), prostate cancer (P = 0.5354), bladder cancer (P = 0.8996), and brain cancer (P = 0.8164). In the validation part of the study results, the causal relationship between dried fruit intake and lung cancer (P = 0.0043), squamous cell lung cancer (P = 0.0136), and breast cancer (P = 0.0192) was determined. After adjusting for the potential impact of confounders, the causal relationship between dried fruit intake and lung cancer (P = 0.0034), squamous cell lung cancer (P = 0.046), and breast cancer (P = 0.0001) remained. The sensitivity analysis showed that our results were stable and reliable. Conclusion: The intake of dried fruits may have a protective effect against some site-specific cancers. Therefore, health education and a reasonable adjustment of dietary proportions may help in the primary prevention of cancer.

7.
Angew Chem Int Ed Engl ; 61(29): e202203631, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35416381

RESUMO

Here we report a new strategy to tune both excitation and emission peaks of upconversion nanoparticles (UCNPs) into the first infrared biowindow (NIR-I, 650-900 nm) with high NIR-I-to-NIR-I upconversion efficiency. By introducing the sensitizer Nd3+ , activator Er3+ , energy migrator Yb3+ and energy manipulator Mn2+ into specific region to construct proposed energy migration processes in the designed core-shell-shell nanoarchitecture, back energy transfer (BET) from activator to sensitizer or migrator can be greatly blocked and the NIR-to-red upconversion emission can be efficiently promoted. Consequently, BET-induced photon quenching and the undesired green-emitting radiative transition are entirely eliminated, leading to high-efficiency single-band red upconversion emission upon 808 nm NIR-I laser excitation. Our findings provide insights into fundamental lanthanide interactions and advance the development of UCNPs for bioapplications with techniques that overturn traditional limitations.

8.
Environ Technol ; 43(10): 1561-1572, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33115346

RESUMO

4-chlorophenol (4-CP) could be rapidly mineralized by using Fenton reaction. However, massive iron sludge will be generated because of the excessive consumption of iron salt and poor recycling of FeIII back to FeII. In this paper, by introducing hydrogen gas and solid catalyst Pd/NH2-MIL-101(Cr) to classic Fenton reactor, the novel system named MHACF-NH2-MIL-101(Cr) was constructed. Much less FeII was needed in this system because the hydrogen could significantly accelerate the regeneration of FeII. The catalyst improved the utilization of H2. The degradation reaction of 4-CP could be driven by using only trace amount of FeII. It could be rapidly degraded by the hydroxyl radical detected by the 4-Hydroxy-benzoicacid which is the oxidative product of benzoic acid and hydroxyl radical. The effects of dosage of ferrous salt, H2O2 and catalyst, H2 flow, Pd content, and initial pH of and concentration of 4-CP aqueous solution were investigated. The robustness and morphology changes of this catalytic material were also systematically analysed. By clarifying the role of this solid MOFs material in this hydrogen-mediated Fenton reaction system, it will provide a new direction for the research and development of advanced oxidation processes with high efficiency and low sludge generation in future.


Assuntos
Peróxido de Hidrogênio , Radical Hidroxila , Clorofenóis , Compostos Férricos , Compostos Ferrosos , Hidrogênio , Peróxido de Hidrogênio/química , Radical Hidroxila/química , Ferro/química , Estruturas Metalorgânicas , Oxirredução , Esgotos
9.
Front Cell Infect Microbiol ; 11: 751795, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34888258

RESUMO

Cholangiocarcinoma (CCA) is a malignant hepatic tumor with a poor prognosis, which needs early diagnosis urgently. The gut microbiota has been shown to play a crucial role in the progression of liver cancer. Here, we explored a gut microbiota model covering genera Burkholderia-Caballeronia-Paraburkholderia, Faecalibacterium, and Ruminococcus_1 (B-F-R) for CCA early diagnosis. A case-control study was conducted to enroll 53 CCA patients, 47 cholelithiasis patients, and 40 healthy controls. The feces samples and clinical information of participants were collected in the same period. The gut microbiota and its diversity of individuals were accessed with 16S rDNA sequencing, and the gut microbiota profile was evaluated according to microbiota diversity. Finally, four enriched genera in the CCA group (genera Bacteroides, Muribaculaceae_unclassified, Muribaculum, and Alistipes) and eight enriched genera in the cholelithiasis group (genera Bifidobacterium, Streptococcus, Agathobacter, Ruminococcus_gnavus_group, Faecalibacterium, Subdoligranulum, Collinsella, Escherichia-Shigella) constitute an overall different microbial community composition (P = 0.001). The B-F-R genera model with better diagnostic value than carbohydrate antigen 19-9 (CA19-9) was identified by random forest and Statistical Analysis of Metagenomic Profiles (STAMP) to distinguish CCA patients from healthy controls [area under the curve (AUC) = 0.973, 95% CI = 0.932-1.0]. Moreover, the correlative analysis found that genera Burkholderia-Caballeronia-Paraburkholderia were positively correlated with body mass index (BMI). The significantly different microbiomes between cholelithiasis and CCA were found via principal coordinates analysis (PCoA) and linear discriminant analysis effect size (LEfSe), and Venn diagram and LEfSe were utilized to identify four genera by comparing microbial compositions among patients with malignant obstructive jaundice (MOJ-Y) or not (MOJ-N). In brief, our findings suggest that gut microbiota vary from benign and malignant hepatobiliary diseases to healthy people and provide evidence supporting gut microbiota to be a non-invasive biomarker for the early diagnosis of CCA.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Microbioma Gastrointestinal , Neoplasias dos Ductos Biliares/diagnóstico , Ductos Biliares Intra-Hepáticos , Estudos de Casos e Controles , Colangiocarcinoma/diagnóstico , Detecção Precoce de Câncer , Fezes , Humanos , RNA Ribossômico 16S/genética
10.
Am J Cancer Res ; 11(8): 3832-3840, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34522452

RESUMO

Accumulating evidence demonstrates that the expression levels of programmed cell death protein 1 (PD-1) and programmed death ligand 1 (PD-L1) are regulated at the various levels, including transcription, post-transcriptional modification and post-translational modifications (PTMs). The PTMs of PD-1/PD-L1 contain phosphorylation, ubiquitination, methylation, glycosylation and palmitoylation. Recently, PD-L1 was reported to be acetylated at Lys263 site by p300 and was deacetylated by histone deacetylase 2 (HDAC2). Acetylation of PD-L1 prevented its translocation to the nucleus and led to a reduction of the nuclear portion of PD-L1, resulting in evading immune surveillance of tumor cells. In this review article, we briefly describe the PTMs of PD-1/PD-L1 and mainly summarize the novel findings of PD-L1 acetylation in tumor cells. Moreover, we discuss the associations of PD-L1 acetylation and ubiquitination, phosphorylation and methylation. Furthermore, we highlight that targeting acetylation of PD-L1 by HDAC inhibitors might be useful for enhancing tumor immunotherapy.

11.
Cell Death Discov ; 7(1): 163, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34226507

RESUMO

Emerging evidence demonstrates that WW domain-containing E3 ubiquitin protein ligase 1 (WWP1) participates into carcinogenesis and tumor progression. In this review article, we will describe the association between dysregulated WWP1 expression and clinical features of cancer patients. Moreover, we summarize the both oncogenic and tumor suppressive functions of WWP1 in a variety of human cancers. Furthermore, we briefly describe the downstream substrates of WWP1 and its upstream factors to regulate the expression of WWP1. Notably, targeting WWP1 by its inhibitors or natural compounds is potentially useful for treating human malignancies. Finally, we provide the perspectives regarding WWP1 in cancer development and therapies. We hope this review can stimulate the research to improve our understanding of WWP1-mediated tumorigenesis and accelerate the discovery of novel therapeutic strategies via targeting WWP1 expression in cancers.

12.
Cancer Med ; 10(14): 4768-4780, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34105304

RESUMO

BACKGROUND: To explore the prognostic value of the fibrinogen-albumin ratio (FAR) combined with sarcopenia in intrahepatic cholangiocarcinoma (ICC) patients after surgery and to develop a nomogram for predicting the survival of ICC patients. MATERIALS AND METHODS: In this prospective cohort study, 116 ICC patients who underwent radical surgery were enrolled as the discovery cohort and another independent cohort of 68 ICC patients was used as the validation cohort. Kaplan-Meier method was used to analyze prognosis. The independent predictor of overall survival (OS) and recurrence-free survival (RFS) was evaluated by univariable and multivariable Cox regression analyses, then developing nomograms. The performance of nomograms was evaluated by concordance index (C-index), calibration curve, receiver operating characteristic curve analysis (ROC), and decision curve analysis (DCA). RESULTS: Patients with high FAR had lower OS and RFS. FAR and sarcopenia were effective predictors of OS and RFS. Patients with high FAR and sarcopenia had a poorer prognosis than other patients. OS nomogram was constructed based on age, FAR, and sarcopenia. RFS nomogram was constructed based on FAR and sarcopenia. C-index for the nomograms of OS and RFS was 0.713 and 0.686. Calibration curves revealed great consistency between actual survival and nomogram prediction. The area under ROC curve (AUC) for the nomograms of OS and RFS was 0.796 and 0.791 in the discovery cohort, 0.823 and 0.726 in the validation cohort. The clinical value of nomograms was confirmed by the DCA. CONCLUSIONS: ICC patients with high FAR and sarcopenia had a poor prognosis, the nomograms developed based on these two factors were accurate and clinically useful in ICC patients who underwent radical resection.


Assuntos
Neoplasias dos Ductos Biliares/mortalidade , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/mortalidade , Fibrinogênio/análise , Sarcopenia/mortalidade , Albumina Sérica/análise , Idoso , Neoplasias dos Ductos Biliares/sangue , Neoplasias dos Ductos Biliares/cirurgia , Biomarcadores Tumorais/sangue , Colangiocarcinoma/sangue , Colangiocarcinoma/cirurgia , Técnicas de Apoio para a Decisão , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Nomogramas , Prognóstico , Intervalo Livre de Progressão , Estudos Prospectivos , Curva ROC , Sarcopenia/sangue
13.
Free Radic Biol Med ; 163: 379-391, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33383086

RESUMO

Acute pancreatitis (AP) is characterized by excessive release of pro-inflammatory cytokines and provokes multiorgan dysfunction. Disruption of the intestinal epithelium often occurs during and following acute pancreatitis and may aggravate systemic organ injuries. Although it has been widely investigated, to date, there is no satisfactory clinical therapy to restore the inflammatory damage. BML-111 is an endogenous lipid mediator that is analogous to LipoxinA4. It has been shown that BML-111 has a stable and potent anti-inflammatory ability. However, it is unclear whether BML-111 is involved in the process of relieving acute pancreatitis and its induced intestinal barrier damage, and the underlying mechanism of this effect. Here, we demonstrated that BML-111 could enhance the expression of E-cadherin, alleviate apoptosis, and mitigate the accumulation of reactive oxygen species in intestinal epithelial cells, thereby contributing to the anti-inflammatory efficacy in vitro and in vivo. Mechanistically, BML-111 upregulates the expression of Nrf2, which is a key regulator of the antioxidant response, and activates its downstream HO-1/NQO-1 pathway to protect against oxidative stress-induced cell death and tissue injury, consequently ameliorating pancreatitis and intestinal epithelium injury. In Nrf2-deficient cell and Nrf2-knockout mouse models, the depletion of Nrf2 blocked BML-111-induced antioxidant effects and thus was unable to exert protective effects in tissue. Taken together, BML-111 attenuated AP-related intestinal injury via an Nrf2-dependent antioxidant mechanism. Targeting this pathway is a potential therapeutic approach for AP-related intestinal injury.


Assuntos
Fator 2 Relacionado a NF-E2 , Pancreatite , Doença Aguda , Animais , Antioxidantes/farmacologia , Ácidos Heptanoicos , Camundongos , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Pancreatite/induzido quimicamente , Pancreatite/tratamento farmacológico , Transdução de Sinais
14.
J Colloid Interface Sci ; 583: 614-625, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33039860

RESUMO

The fabrication of high-performance and stable electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is of importance for sustainable water-splitting technologies. Herein, the cobalt (Co) nanoparticles and molybdenum carbide (Mo2C) heterostructures anchored N-doped carbon (Co/Mo2C@NC-800) was designed as bifunctional electrocatalyst for overall water splitting via a simple pyrolysis approach for metal organic frameworks (MOFs) precursor. This composite shows a remarkable performance for HER and OER with a small overpotential of 121 mV and 311 mV at 10 mA cm-2, respectively. When the optimized electrocatalyst was employed as both anode and cathode for overall water splitting in a two-electrode system, the electrolyzer achieves a low cell voltage of 1.67 V at 10 mA cm-2 in 1 M KOH, as well as a superior and stable long-time operation of 30 h. The promising hybrid material demonstrates excellent electrocatalysis performance due to effective combination of the best of both worlds: Mo2C with remarkable HER performance and Co nanoparticles with excellent OER activity. The Mo2C possesses strong hydrogen binding energy and Co exhibits prominent electrical conductivity, thus the construction of heterostructures achieves more active sites with different functions and significantly boosts HER and OER process. The novel and effective synthesis strategy provides new insights into the design of outstanding non-noble metal bifunctional electrocatalysts for overall water splitting.

15.
Sensors (Basel) ; 20(19)2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-33003284

RESUMO

Biosensors are widely used in production and life, and can be used in medicine, industrial production, and scientific research. Among them, the detection of pH has always received extensive attention. In this study, we demonstrate the use of a one-step hydrothermal method to prepare Co-FeS2/CoS2 nanomaterials as pH sensor (pH vs. overpotential) for the first time. The proposed pH sensor exhibits outstanding performance in KOH solutions via electrochemical methods with good stability. Overall, the results of this study not only add to the non-noble transition metal electrocatalysis research, but also identify important sensing characteristics for electrocatalysts.

16.
Nanomaterials (Basel) ; 10(11)2020 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-33114399

RESUMO

Transition metal sulfides are cheap and efficient catalysts for water splitting to produce hydrogen; these compounds have attracted wide attention. Nickel sulfide (NiS2) has been studied in depth because of its simple preparation process, excellent performance and good stability. Here, we propose a modification to the hydrothermal synthesis method for the fabrication of a highly efficient and stable NiS2 electrocatalyst prepared by two different sulfur sources, i.e., sulfur powder and C3H7NaO3S2 (MPS), for application in hydrogen evolution reactions. The obtained NiS2 demonstrated excellent HER performance with an overpotential of 131 mV to drive -10 mA cm-1 in 0.5 M H2SO4 solution with 5mV performance change after 1000 cycles of stability testing. We believe that this discovery will promote the industrial development of nonprecious metal catalysts.

17.
J Am Chem Soc ; 142(42): 17933-17937, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-33043669

RESUMO

The coupling of material systems at different length scales enables new ways to take advantage of the unique properties of nano-/macroscale materials. Here, the self-organization of assembled metallacages generated ultralong nanowires, followed by the formation of nanowire-based soft films with diameters up to 6.5 cm. In contrast to previous reports that mainly focused on the preparation of metallacage assemblies with dimensions on the nano-/micrometer scale, the preparation of centimeter assemblies can serve as the bridge between nanostructures and the macroscopic world.

18.
J Nanosci Nanotechnol ; 20(3): 1832-1837, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492349

RESUMO

Tin monoxide is a kind of IV-VI metal monoxides that has attracted great deal of attention due to its wide optical band gap and high field effect mobility in the past decade. On the other hand, nanoshell is a unique porous structure. Its curved shell provides a shelter for the hollow core, as well as a much bigger special surface area. We in this study systematically prepared SnO nanoshells through a facile self-assembly method under different annealing conditions. The lithium ion batteries were fabricated immediately based on the as prepared nanoshells. The capacity of as fabricated lithium ion batteries was 559.3 mAhg-1 at rate performance of 0.1 Ag-1 and 497.5 mAhg-1 at 1 Ag-1 in 30th cycle. This work exhibited high application performance of SnO nanoshells. We hope this work will help study similar structure and applications of IV-VI metal monoxides.

19.
Chem Commun (Camb) ; 55(90): 13566-13569, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31650993

RESUMO

Ultrasmall and homogeneous bimetallic PdxBi nanoalloys are well distributed on a Vulcan carbon support by a facile, low-cost synthetic strategy. The electrochemical activity of the as-prepared homogeneous PdxBi nanoalloy/carbon black nanocomposites is closely related to the content of Bi, revealing their excellent electrocatalytic performance for selective oxidation of monohydric alcohols and vicinal diols in alkali medium.

20.
ChemSusChem ; 12(22): 5015-5022, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31538408

RESUMO

2 D transition metal dichalcogenide materials with layered nanostructures and specific phases usually exhibit excellent catalytic activities for the hydrogen evolution reaction (HER). A facile solvothermal process was used to prepare ultrathin noble-metal-free 2 D biphasic MoSe2 nanosheets composed of a metastable metallic 1T phase and a semiconducting 2H phase. High metallic 1T phase content and few-layer-thick MoSe2 nanosheets were obtained by tuning the amount of NaBH4 used in the reaction. The optimal integration of a metallic 1T phase and an environmentally stable 2H phase in MoSe2 electrocatalysts provides abundant active sites and good conductivity beneficial for the HER. The combination of experimental results and DFT calculations implies that the electrocatalytic activity for the HER on the MoSe2 surface goes through a collaborative Heyrovsky and Volmer reaction process. The theoretical studies suggest that the presence of 1T-MoSe2 could reduce the band energy relative to 2H-MoSe2 and, consequently, accelerate the sluggish HER kinetics of 2H-MoSe2 . This work provides valuable and novel insights into the understanding of the structure-activity relationships in 2 D transition metal dichalcogenide electrocatalysts.

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