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1.
Small ; : e2403448, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38881353

RESUMO

Alcohol electrooxidation is pivotal for a sustainable energy economy. However, designing efficient electrocatalysts for this process is still a formidable challenge. Herein, palladium-selenium nanowires featuring distinct crystal phases: monoclinic Pd7Se2 and tetragonal Pd4.5Se for ethylene glycol electrooxidation reaction (EGOR) are synthesized. Notably, the supported monoclinic Pd7Se2 nanowires (m-Pd7Se2 NWs/C) exhibit superior EGOR activity, achieving a mass activity (MA) and specific activity (SA) of 10.4 A mgPd -1 (18.7 mA cm-2), which are 8.0 (6.7) and 10.4 (8.2) times versus the tetragonal Pd4.5Se and commercial Pd/C and surpass those reported in the literature. Furthermore, m-Pd7Se2 NWs/C displays robust catalytic activity for other alcohol electrooxidation. Comprehensive characterization and density functional theory (DFT) calculations reveal that the enhanced electrocatalytic performance is attributed to the increased formation of Pd0 on the high-index facets of the m-Pd7Se2 NWs, which lowers the energy barriers for the C─C bond dissociation in CHOHCHOH* and the CO* oxidation to CO2*. This study provides palladium-based alloy electrocatalysts exhibiting the highest mass activity reported to date for the electrooxidation of ethylene glycol, achieved through the crystalline phase engineering strategy.

2.
Nat Nanotechnol ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918614

RESUMO

Constructing regioselective architectures in heterostructures is important for many applications; however, the targeted design of regioselective architectures is challenging due to the sophisticated processes, impurity pollution and an unclear growth mechanism. Here we successfully realized a one-pot kinetically controlled synthetic framework for constructing regioselective architectures in metallic heterostructures. The key objective was to simultaneously consider the reduction rates of metal precursors and the lattice matching relationship at heterogeneous interfaces. More importantly, this synthetic method also provided phase- and morphology-independent behaviours as foundations for choosing substrate materials, including phase regulation from Pd20Sb7 hexagonal nanoplates (HPs) to Pd8Sb3 HPs, and morphology regulation from Pd20Sb7 HPs to Pd20Sb7 rhombohedra and Pd20Sb7 nanoparticles. Consequently, the activity of regioselective epitaxially grown Pt on Pd20Sb7 HPs was greatly enhanced towards the ethanol oxidation reaction; its activity was 57 times greater than that of commercial Pt/C, and the catalyst showed increased stability (decreasing by 16.3% after 2,000 cycles) and selectivity (72.4%) compared with those of commercial Pt/C (56.0%, 18.2%). This work paves the way for the design of unconventional well-defined heterostructures for use in various applications.

3.
Lipids Health Dis ; 23(1): 170, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849832

RESUMO

BACKGROUND: Gestational diabetes mellitus (GDM) prevalence is on the rise globally. Offspring of diabetic mothers face increased risk of neonatal hypoglycaemia (NH), and women with GDM have abnormal lipid profiles. However, there is no consensus on the link between maternal blood lipids and NH in infants from mothers with GDM. This study aimed to explore how maternal blood lipids affect NH. METHODS: A retrospective cohort study was conducted at the First Affiliated Hospital of Sun Yat-sen University. Information on participants' baseline characteristics and maternal metabolic profiles of glucose and lipids was collected. Significant variables from the univariate analysis were included in logistic regression, which was used to construct the predictive model for NH. A nomogram was constructed for visualizing the model and assessed using the area under the receiver operating characteristic (ROC) curve (AUC). RESULTS: Neonatal capillary blood glucose (CBG) decreased rapidly in the first hour after birth, increased gradually from the first to the second hour, and then remained stable. In the NH group, 86.11% (502/583) of hypoglycaemia cases occurred within the first two hours after birth. Multivariate logistic regression suggested that the lipid indices of maternal apoprotein B/apoprotein A1 (Apo-B/Apo-A1) (odds ratio (OR) = 1.36, 95% confidence intervals (CIs): 1.049-1.764, P = 0.02) and apoprotein E (Apo-E) (OR = 1.014, 95% CIs: 1.004-1.024, P = 0.004) were positively associated with NH in neonates from mothers with GDM. Triglycerides (TGs) (OR = 0.883, 95% CIs: 0.788-0.986, P = 0.028) were inversely associated with NH. Maternal glycated haemoglobin (HbA1c), age, twin pregnancy and caesarean delivery also had predictive value of NH. The AUC of the nomogram derived from these factors for the prediction model of NH was 0.657 (95% CIs: 0.630-0.684). CONCLUSIONS: The present study revealed that the Apo-B/Apo-A1 and Apo-E levels were associated with an increased risk of NH. A nomogram was developed to forecast the risk of NH in babies born to mothers with GDM, incorporating maternal blood lipids, HbA1c, age, twin pregnancy, and caesarean section. The trajectory of glycaemia for neonates indicates the need for intensive CBG monitoring within 2 h of birth for neonates from mothers with GDM.


Assuntos
Glicemia , Diabetes Gestacional , Hipoglicemia , Humanos , Feminino , Gravidez , Diabetes Gestacional/sangue , Hipoglicemia/sangue , Recém-Nascido , Adulto , Glicemia/metabolismo , Glicemia/análise , Estudos Retrospectivos , Lipídeos/sangue , Curva ROC , Modelos Logísticos , Fatores de Risco
4.
Nano Lett ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38900138

RESUMO

Developing highly efficient and carbon monoxide (CO)-tolerant platinum (Pt) catalysts for the formic acid oxidation reaction (FAOR) is vital for direct formic acid fuel cells (DFAFCs), yet it is challenging due to the high energy barrier of direct intermediates (HCOO* and COOH*) as well as the CO poisoning issues associated with Pt alloy catalysts. Here we present a versatile biphasic strategy by creating a hexagonal/cubic crystalline-phase-synergistic PtPb/C (h/c-PtPb/C) catalyst to tackle the aforementioned issues. Detailed investigations reveal that h/c-PtPb/C can simultaneously facilitate the adsorption of direct intermediates while inhibiting CO adsorption, thereby significantly improving the activation and CO spillover. As a result, h/c-PtPb/C showcases an outstanding FAOR activity of 8.1 A mgPt-1, which is 64.5 times higher than that of commercial Pt/C and significantly surpasses monophasic PtPb. Moreover, the h/c-PtPb/C-based membrane electrode assembly exhibits an exceptional peak power density of 258.7 mW cm-2 for practical DFAFC applications.

5.
Nano Lett ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38904300

RESUMO

Developing efficient and CO-tolerant platinum (Pt)-based anodic catalysts is challenging for a direct formic acid fuel cell (DFAFC). Herein, we report heterostructured Pt-lead-sulfur (PtPbS)-based nanomaterials with gradual phase regulation as efficient formic acid oxidation reaction (FAOR) catalysts. The optimized Pt-PbS nanobelts (Pt-PbS NBs/C) display the mass and specific activities of 5.90 A mgPt-1 and 21.4 mA cm-2, 2.2/1.2, 1.5/1.1, and 36.9/79.3 times greater than those of PtPb-PbS NBs/C, Pt-PbSO4 NBs/C, and commercial Pt/C, respectively. Simultaneously, it exhibits a higher membrane electrode assembly (MEA) power density (183.5 mW cm-2) than commercial Pt/C (40.3 mW cm-2). This MEA stably operates at 0.4 V for 25 h, demonstrating a competitive potential of device application. The distinctive heterostructure endows the Pt-PbS NBs/C with optimized dehydrogenation steps and resisting the CO poisoning, thus presenting the remarkable FAOR performance. This work paves an effective avenue for creating high-performance anodic catalysts for fuel cells and beyond.

6.
Natl Sci Rev ; 11(6): nwae153, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38800666

RESUMO

Vesicle, a microscopic unit that encloses a volume with an ultrathin wall, is ubiquitous in biomaterials. However, it remains a huge challenge to create its inorganic metal-based artificial counterparts. Here, inspired by the formation of biological vesicles, we proposed a novel biomimetic strategy of curling the ultrathin nanosheets into nanovesicles, which was driven by the interfacial strain. Trapped by the interfacial strain between the initially formed substrate Rh layer and subsequently formed RhRu overlayer, the nanosheet begins to deform in order to release a certain amount of strain. Density functional theory (DFT) calculations reveal that the Ru atoms make the curling of nanosheets more favorable in thermodynamics applications. Owing to the unique vesicular structure, the RhRu nanovesicles/C displays excellent hydrogen oxidation reaction (HOR) activity and stability, which has been proven by both experiments and DFT calculations. Specifically, the HOR mass activity of RhRu nanovesicles/C are 7.52 A mg(Rh+Ru)-1 at an overpotential of 50 mV at the rotating disk electrode (RDE) level; this is 24.19 times that of commercial Pt/C (0.31 mA mgPt-1). Moreover, the hydroxide exchange membrane fuel cell (HEMFC) with RhRu nanovesicles/C displays a peak power density of 1.62 W cm-2 in the H2-O2 condition, much better than that of commercial Pt/C (1.18 W cm-2). This work creates a new biomimetic strategy to synthesize inorganic nanomaterials, paving a pathway for designing catalytic reactors.

7.
Physiol Meas ; 45(5)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38688301

RESUMO

Objective.Intermittent hypoxia, the primary pathology of obstructive sleep apnea (OSA), causes cardiovascular responses resulting in changes in hemodynamic parameters such as stroke volume (SV), blood pressure (BP), and heart rate (HR). However, previous studies have produced very different conclusions, such as suggesting that SV increases or decreases during apnea. A key reason for drawing contrary conclusions from similar measurements may be due to ignoring the time delay in acquiring response signals. By analyzing the signals collected during hypoxia, we aim to establish criteria for determining the delay time between the onset of apnea and the onset of physiological parameter response.Approach.We monitored oxygen saturation (SpO2), transcutaneous oxygen pressure (TcPO2), and hemodynamic parameters SV, HR, and BP, during sleep in 66 patients with different OSA severity to observe body's response to hypoxia and determine the delay time of above parameters. Data were analyzed using the Kruskal-Wallis test, Quade test, and Spearman test.Main results.We found that simultaneous acquisition of various parameters inevitably involved varying degrees of response delay (7.12-25.60 s). The delay time of hemodynamic parameters was significantly shorter than that of SpO2and TcPO2(p< 0.01). OSA severity affected the response delay of SpO2, TcPO2, SV, mean BP, and HR (p< 0.05). SV delay time was negatively correlated with the apnea-hypopnea index (r= -0.4831,p< 0.0001).Significance.The real body response should be determined after removing the effect of delay time, which is the key to solve the problem of drawing contradictory conclusions from similar studies. The methods and important findings presented in this study provide key information for revealing the true response of the cardiovascular system during hypoxia, indicating the importance of proper signal analysis for correctly interpreting the cardiovascular hemodynamic response phenomena and exploring their physiological and pathophysiological mechanisms.


Assuntos
Hipóxia , Apneia Obstrutiva do Sono , Humanos , Apneia Obstrutiva do Sono/fisiopatologia , Hipóxia/fisiopatologia , Masculino , Fatores de Tempo , Feminino , Pessoa de Meia-Idade , Adulto , Hemodinâmica , Frequência Cardíaca , Saturação de Oxigênio , Pressão Sanguínea/fisiologia , Processamento de Sinais Assistido por Computador
8.
Chem Sci ; 15(11): 3928-3935, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38487225

RESUMO

Anion exchange membrane fuel cells are a potentially cost-effective energy conversion technology, however, the electrocatalyst for the anodic hydrogen oxidation reaction (HOR) suffers from sluggish kinetics under alkaline conditions. Herein, we report that Ru-based nanosheets with amorphous-crystalline heterointerfaces of Ru and Ti-doped RuO2 (a/c-Ru/Ti-RuO2) can serve as a highly efficient HOR catalyst with a mass activity of 4.16 A mgRu-1, which is 19.8-fold higher than that of commercial Pt/C. Detailed characterization studies show that abundant amorphous-crystalline heterointerfaces of a/c-Ru/Ti-RuO2 nanosheets provide oxygen vacancies and unsaturated coordination bonds for balancing adsorption of hydrogen and hydroxyl species on Ru active sites to elevate HOR activity. Moreover, Ti doping can facilitate CO oxidation, leading to enhanced strength to CO poisoning. This work provides a strategy for enhancing alkaline HOR performance over Ru-based catalysts with heteroatom and heterointerface dual-engineering, which will attract immediate interest in chemistry, materials science and beyond.

9.
Analyst ; 149(7): 1971-1975, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38439614

RESUMO

Herein, we present toxicological assessments of carbon nanomaterials in HL-7702 cells, and it was found that reactive oxygen species (ROS) levels were elevated. Mass spectrometry results indicated that cysteine sulfhydryl of glutaredoxin-1 (GLRX1) was oxidized to sulfenic acids and sulfonic acids by excessive ROS, which broke the binding of GLRX1 to apoptosis signal-regulating kinase 1, causing the activation of the JNK/p38 signaling pathway and ultimately hepatocyte apoptosis. However, a lower level of ROS upregulated GLRX1 instead of sulfonation modification of its active sites. Highly expressed GLRX1 in turn enabled the removal of intracellular ROS, thereby exerting inconspicuous toxic effects on cells. Taken together, these findings emphasized that CNM-induced hepatotoxicity is attributable to oxidative modifications of GLRX1 arising from redox imbalance.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Glutarredoxinas , Humanos , Espécies Reativas de Oxigênio/metabolismo , Glutarredoxinas/genética , Glutarredoxinas/metabolismo , Glutarredoxinas/farmacologia , Oxirredução , Apoptose , Estresse Oxidativo
10.
ACS Nano ; 18(14): 10008-10018, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38551183

RESUMO

Two-dimensional (2D) heterojunction nanomaterials offer exceptional physicochemical and catalytic properties, thanks to their special spatial electronic structure. However, synthesizing morphologically uniform 2D platinum (Pt)-based metallic nanomaterials with diverse crystalline phases remains a formidable challenge. In this study, we have achieved the successful synthesis of advanced 2D platinum-tellurium heterojunction nanosheet assemblies (Ptx-PtTe2 HJNSAs, x = 0, 1, 2), seamlessly integrating both trigonal PtTe2 (t-PtTe2) and cubic Pt (c-Pt) phases. By enabling efficient electron transport and leveraging the specific electron density present at the heterojunction, the Pt2-PtTe2 HJNSAs/C demonstrated exceptional formic acid oxidation reaction (FAOR) activity and stability. Specifically, the specific and mass activities reached 8.4 mA cm-2 and 6.1 A mgPt-1, which are 46.7 and 50.8 times higher than those of commercial Pt/C, respectively. Impressively, aberration-corrected high-angle annular dark field scanning transmission electron microscopy (AC-HAADF-STEM) revealed a closely packed arrangement of atomic layers and a coherent intergrowth heterogeneous structure. Density functional theory (DFT) calculations further indicated that rearrangement of electronic structure occurred on the surface of Pt2-PtTe2 HJNSAs resulting in a more favorable dehydrogenation pathway and excellent CO tolerance, beneficial for performance improvement. This work inspires the targeted exploration of Pt-based nanomaterials through 2D heterostructure design, leading to an important impact on fuel cell catalysis and beyond.

11.
Anal Chem ; 96(10): 4138-4145, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38426857

RESUMO

Calcification and abnormal collagen deposition within blood vessels constitute causative factors for atherosclerotic plaque rupture, and their occurrence is intimately linked with γ-glutamyltranspeptidase (GGT) and hypobromous acid (HOBr). However, the underlying regulatory mechanisms of GGT and HOBr in plaque rupture remain unclear. Hence, we developed a dual-responsive near-infrared (NIR) fluorescent probe (BOC-H) that effectively avoids spectral crosstalk for the in situ visualization of the fluctuations in GGT and HOBr levels during atherosclerotic plaque rupture. We found that both GGT and HOBr contents increase significantly in the calcification models of cells and animals. The overexpressed GGT participated in intracellular oxygen-promoting behavior, which obviously upregulated the expression of RunX2 and Col IV by facilitating H2O2 and HOBr secretion. This process triggered calcification and abnormal collagen deposition within the plaque, which raised the risk of plaque rupture. PM2.5-induced arteriosclerotic calcification models further verified the results that GGT and HOBr accelerate plaque rupture via activation of the RunX2/Col IV signaling pathway. Moreover, the assessment of GGT and HOBr in serum samples from patients with acute myocardial infarction further confirmed the co-regulation of GGT and HOBr in the plaque rupture. Together, our studies highlight the involvement of GGT and HOBr in driving plaque rupture and offer new targets for the prevention and treatment of acute cardiovascular disease.


Assuntos
Bromatos , Placa Aterosclerótica , Animais , Humanos , Placa Aterosclerótica/diagnóstico por imagem , Peróxido de Hidrogênio , Transdução de Sinais , Colágeno
13.
J Thorac Dis ; 16(2): 1378-1387, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38505045

RESUMO

Background: Chronic obstructive pulmonary disease (COPD) affects up to 13% of the Chinese population, though it is under diagnosed throughout China. Screening among asymptomatic individual as part of routine health checks in China can facilitate early diagnosis and intervention to prevent disease progress. The COPD Population Screener (COPD-PS) or COPD Screening Questionnaire (COPD-SQ) has yet to be applied in Chinese physical examination centers (PECs) for COPD screening, and their feasibility and effectiveness should be clarified before full-scale implementation. This study is the first to apply the COPD-PS and COPD-SQ in a public hospital PEC in China to assess their feasibility and effectiveness and to identify their optimal cutoff values. Methods: People aged ≥40 years who attended the Second Affiliated Hospital of Shantou University PECs from September 2021 to December 2022 were asked to complete the COPD-PS and COPD-SQ and to undergo spirometry. The optimal cutoff values of the two questionnaires at the maximal Youden index were found, and the sensitivity and specificity were calculated. Results: Data from 198 participants were analyzed; mean [standard deviation (SD)] age of patients was 63.52 (10.94) years. Twenty-five participants (12.63%) were diagnosed with COPD. The number of COPD patients classified as Global Initiative for Chronic Obstructive Lung Disease (GOLD) grades 1 to 4 were 8, 12, 4, and 1, respectively. The area under the curves (AUCs) of the COPD-PS and COPD-SQ were 0.730 and 0.738, respectively. The optimal COPD-PS cutoff value of 4 points corresponded to a sensitivity of 72.00% and a specificity of 60.10%. The COPD-SQ optimal cutoff value of 15 points corresponded to a sensitivity of 76.00% and a specificity of 63.60%. Conclusions: Applying the COPD-PS and COPD-SQ in Chinese PECs is feasible, cost-effective and effective. COPD-PS and COPD-SQ can facilitate the early diagnosis of COPD, and whether they can improve the participants' quality of life would benefit a further study. It is recommended that the COPD-PS or COPD-SQ questionnaires be added to the screening of the physical examination program in PECs as part of health checks for people over 40 years old.

14.
BMC Infect Dis ; 24(1): 202, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355432

RESUMO

BACKGROUND: This study aimed to assess the relationship between a low serum free triiodothyronine (FT3) level and the mortality of severe pulmonary tuberculosis (TB) patients. METHODS: We performed a retrospective study and reviewed the medical records of patients with severe pulmonary TB between January 2016 and June 2022. The patient demographics, Acute Physiology and Chronic Health Evaluation (APACHE) II score, survival or death at 28 and 90 days after hospital admission, and serum FT3 level were recorded. Bivariate regression analysis was performed to study the relationship between mortality and the FT3 level. The Kaplan-Meier method and the log-rank test were used to compare the survival rates between patients with different serum FT3 levels. RESULTS: Our study included 495 severe pulmonary TB patients, with 383 (77.4%) patients having a low serum FT3 level. The low-serum FT3 group had high 28-day and 90-day mortalities. The patients who had died by 28 or 90 days after hospital admission had a low FT3 level. Survival analysis showed that the patients with a low serum FT3 level had a low probability of survival at 28 days and at 90 days after hospital admission. CONCLUSION: The serum FT3 level was correlated with the 28-day and 90-day mortalities in patients with severe pulmonary TB. The serum FT3 level should be monitored in these patients to help manage their disease.


Assuntos
Tri-Iodotironina , Tuberculose Pulmonar , Humanos , Estudos Retrospectivos , Análise de Regressão , Análise de Sobrevida , Prognóstico
15.
Clin Lab ; 70(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38345968

RESUMO

BACKGROUND: This study aims to investigate the clinical characteristics associated with concurrent Klebsiella pneu-moniae (K. pneumoniae) infection in hospitalized patients with severe pulmonary tuberculosis. METHODS: A retrospective study was conducted on hospitalized severe pulmonary tuberculosis patients between January 2019 and December 2020. Among the 487 patients with severe pulmonary tuberculosis, a positive sputum culture for K. pneumoniae was reported in 76 patients (15.6%, 61 males and 15 females). RESULTS: Among these patients, 27 (35.5%) and 49 (64.5%) patients were with and without K. pneumoniae infection, respectively. Compared to patients without K. pneumoniae infection, patients with K. pneumoniae infection had higher mortality (16.3% vs. 40.7%, p = 0.02), and lower inhibitory/cytotoxic CD8 count (24.2 ± 9.9 vs. 17.8 ± 8.0, p = 0.02), complement C4 (0.3 ± 0.1 vs. 0.2 ± 0.1, p = 0.01), and retinol-binding protein level (32.2 ± 22.2 vs. 22.4 ± 11.8, p = 0.02). Furthermore, the acute Physiology and Chronic Health Evaluation II score was associated with the K. pneumoniae infection in severe pulmonary tuberculosis patients. CONCLUSIONS: It can be concluded that a significant number of severe pulmonary tuberculosis patients can have concurrent K. pneumoniae infection. Immunity, nutritional status, and disease severity are associated with the concurrent infection of K. pneumoniae in these patients.


Assuntos
Infecções por Klebsiella , Tuberculose Pulmonar , Masculino , Feminino , Humanos , Klebsiella pneumoniae , Estudos Retrospectivos , Infecções por Klebsiella/complicações , Infecções por Klebsiella/diagnóstico , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/diagnóstico , Antibacterianos
16.
Nat Commun ; 15(1): 1097, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321034

RESUMO

Bimetallic PtRu are promising electrocatalysts for hydrogen oxidation reaction in anion exchange membrane fuel cell, where the activity and stability are still unsatisfying. Here, PtRu nanowires were implanted with a series of oxophilic metal atoms (named as i-M-PR), significantly enhancing alkaline hydrogen oxidation reaction (HOR) activity and stability. With the dual doping of In and Zn atoms, the i-ZnIn-PR/C shows mass activity of 10.2 A mgPt+Ru-1 at 50 mV, largely surpassing that of commercial Pt/C (0.27 A mgPt-1) and PtRu/C (1.24 A mgPt+Ru-1). More importantly, the peak power density and specific power density are as high as 1.84 W cm-2 and 18.4 W mgPt+Ru-1 with a low loading (0.1 mg cm-2) anion exchange membrane fuel cell. Advanced experimental characterizations and theoretical calculations collectively suggest that dual doping with In and Zn atoms optimizes the binding strengths of intermediates and promotes CO oxidation, enhancing the HOR performances. This work deepens the understanding of developing novel alloy catalysts, which will attract immediate interest in materials, chemistry, energy and beyond.

17.
Angew Chem Int Ed Engl ; 63(11): e202318028, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38179810

RESUMO

Since the discovery of graphene, the development of new two-dimensional (2D) materials has received considerable interest. Recently, as a newly emerging member of the 2D family, 2D metastable-phase oxides that combine the unique advantages of metal oxides, 2D structures, and metastable-phase materials have shown enormous potential in various catalytic reactions. In this review, the potential of various 2D materials to form a metastable-phase is predicted. The advantages of 2D metastable-phase oxides for advanced applications, reliable methods of synthesizing 2D metastable-phase oxides, and the application of these oxides in different catalytic reactions are presented. Finally, the challenges associated with 2D metastable-phase oxides and future perspectives are discussed.

18.
Adv Mater ; 36(18): e2312140, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38241656

RESUMO

Noble metals have been widely used in catalysis, however, the scarcity and high cost of noble metal motivate researchers to balance the atomic efficiency and atomic density, which is formidably challenging. This article proposes a robust strategy for fabricating 3D amorphous noble metal-based oxides with simultaneous enhancement on atomic efficiency and density with the assistance of atomic channels, where the atomic utilization increases from 18.2% to 59.4%. The unique properties of amorphous bimetallic oxides and formation of atomic channels have been evidenced by detailed experimental characterizations and theoretical simulations. Moreover, the universality of the current strategy is validated by other binary oxides. When Cu2IrOx with atomic channels (Cu2IrOx-AE) is used as catalyst for oxygen evolution reaction (OER), the mass activity and turnover frequency value of Cu2IrOx-AE are 1-2 orders of magnitude higher than CuO/IrO2 and Cu2IrOx without atomic channels, largely outperforming the reported OER catalysts. Theoretical calculations reveal that the formation of atomic channels leads to various Ir sites, on which the proton of adsorbed *OH can transfer to adjacent O atoms of [IrO6]. This work may attract immediate interest of researchers in material science, chemistry, catalysis, and beyond.

19.
Nano Lett ; 24(4): 1205-1213, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38214250

RESUMO

Amorphous nanomaterials have drawn extensive attention owing to their unique features, while amorphization on noble metal nanomaterials still remains formidably challenging. Herein, we demonstrate a universal strategy to synthesize amorphous Pd-based nanomaterials from unary to quinary metals through the introduction of phosphorus (P). The amorphous Pd-based nanoparticles (NPs) exhibit generally promoted oxygen reduction reaction (ORR) activity and durability compared with their crystalline counterparts. Significantly, the quinary P-PdCuNiInSn NPs, benefiting from the amorphous structure and multimetallic component effect, exhibit mass activities as high as 1.04 A mgPd-1 and negligible activity decays of 1.8% among the stability tests, which are much better than values for original Pd NPs (0.134 A mgPd-1 and 28.4%). Experimental and theoretical analyses collectively reveal that the synergy of P-induced amorphization and the expansion of metallic components can considerably lower the free energy changes in the rate-determined step, thereby explaining the positive correlation with the catalytic activity.

20.
Dalton Trans ; 53(2): 552-563, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38054240

RESUMO

Ferrocenyl derivatives and organometallic iridium(III) complexes have been prospective substitutes for platinum-based anticancer drugs. Eight half-sandwich iridium(III) ferrocene-thiosemicarbazide (Fc-TSC) Schiff base anticancer complexes were prepared in this study. These complexes displayed a dimeric structure and exhibited a particular fluorescence due to the "enol" orientation of the TSC pro-ligand. An energy-dependent pathway of the uptake mechanism was ascertained, which ended in the lysosome and led to lysosome damage and apoptosis. Flow cytometry confirmed that the complexes could block the cell cycle (G1 phase) and improve the levels of intracellular reactive oxygen species, indicating an anticancer mechanism of oxidation. Then, a lysosomal-mitochondrial anticancer pathway was verified through western blotting. In vivo toxicity assays confirmed that these complexes showed better anti-migration ability and less toxicity in comparison to cisplatin. Thus, these complexes provide a new strategy for the design of non-platinum organometallic anticancer drugs.


Assuntos
Antineoplásicos , Complexos de Coordenação , Irídio/farmacologia , Irídio/química , Bases de Schiff/farmacologia , Metalocenos/farmacologia , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Estudos Prospectivos , Antineoplásicos/farmacologia , Antineoplásicos/química , Apoptose , Espécies Reativas de Oxigênio/metabolismo , Proliferação de Células , Linhagem Celular Tumoral
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