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1.
Small ; 19(52): e2306014, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37635098

RESUMEN

2D metallene possess high surface area and excellent electron transport capability, thus enabling efficient application in oxygen reduction reaction (ORR). However, the interface regulation and electronic structure optimization of metallene are still great challenges. Herein, Pd-B/Pd hetero-metallene is constructed by interface engineering and B modification strategies for efficient electrocatalytic ORR. The 2D configuration of Pd-B/Pd hetero-metallene exposes a large number of surface atoms and unsaturated defect sites, thus providing abundant catalytic active sites and exhibiting high electron mobility. More importantly, interface engineering and B modification synergistically optimizing the electronic configuration of the metallene system. This work not only provides an effective strategy for the rational regulation of the electronic configuration of metallene, but also offers a reference for the construction of efficient ORR catalysts.

2.
Small ; 19(25): e2300388, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36932943

RESUMEN

Metallene with outstanding physicochemical properties is an efficient two-dimensional electrocatalysts for sustainable hydrogen (H2 ) production applications. However, the controllable fabrication of extended atomically thin metallene nanoribbons remains a formidable challenge. Herein, this work proposes a controllable preparation strategy for atomically thin defect-rich PdIr bimetallene nanoribbons (PdIr BNRs) with a thickness of only 1.5 nm for the efficient and stable isopropanol-assisted seawater electrolytic H2 production. When using PdIr BNRs as catalyst to build an isopropanol-assisted seawater electrolysis system, a voltage of only 0.38 V is required at @10 mA cm-2 to achieve energy-saving H2 production, while producing high value-added acetone at the anode. The aberration-corrected high-resolution transmission electron microscopy (HRTEM) clearly reveals that the PdIr BNRs possess abundant structural defects, which can additionally serve as highly catalytically active sites. Density functional theory (DFT) calculations combined with X-ray absorption spectroscopy studies reveal that the introduction of Ir atoms can induce the formation of a localized charge region and shift the d-band center of Pd down, thereby reducing the adsorption energy on the catalyst in favor of the rapid desorption of H2 . This work opens the way for the controllable design and construction of defect-rich atomically thin metallene nanoribbons for efficient electrocatalytic applications.

3.
Inorg Chem ; 62(37): 15157-15163, 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37658811

RESUMEN

Pd-based metallene is regarded as an efficient catalyst in the field of oxygen reduction reaction (ORR) because of its fantastic physicochemical features. The morphological structure control, lattice strain engineering, and electronic structure modulation of Pd-based metallene are effective tactics to enhance its electrocatalytic performance. In this work, we fabricate atomically thin B-doped Pd metallene nanoribbons (B-Pd MNRs) for efficient alkaline ORR. The atomically thin nanoribbon structure of B-Pd MNRs can expose many surface atoms as catalytically active sites. Moreover, the incorporation of boron effectively induces the lattice expansion and modulates the electronic structure of Pd, which can synergistically weaken the adsorption of intermediate species on B-Pd MNRs. Therefore, the B-Pd MNRs display excellent activity and durability for ORR. This work opens an avenue to the synthesis of atomically thin heteroatom-doped metallene nanoribbons for energy electrocatalytic applications.

4.
Inorg Chem ; 62(35): 14477-14483, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37610771

RESUMEN

The research on high-efficiency two-dimensional (2D) catalytic materials for the small-molecule oxidation-assisted hydrogen evolution reaction (HER) is prospective for efficient hydrogen production. Herein, we report heterostructured Pt/Rh metallene with Pt nanoparticles (NPs) uniformly anchored on Rh metallene for the HER and ethylene glycol oxidation reaction (EGOR). The ultrathin sheet structure of the Pt/Rh metallene offers high surface areas and sufficient active sites. More importantly, the Pt/Rh heterostructure can optimize catalytic active centers and adjust electronic structure. Thus, Pt/Rh metallene exhibits superior electrocatalytic HER activity with a low overpotential of 28 mV in 1 M KOH at 10 mA cm-2 and EGOR activity with a specific activity of 8.39 mA cm-2 in 1 M KOH with 3 M EG, along with outstanding CO tolerance. In a two-electrode system, Pt/Rh metallene requires a low potential of 0.51 V for stable and efficient hydrogen production at 10 mA cm-2 in 1 M KOH + 3 M EG, with the simultaneous production of high-value-added products. The job proposes an attractive strategy for the synthesis of 0D/2D metallene toward simultaneous energy-saving hydrogen production and chemical update.

5.
Nanotechnology ; 34(28)2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37023728

RESUMEN

Controlling the morphology and composition of Pd-based catalysts is the key to construct highly efficient electrocatalysts for cathodic oxygen reduction reaction (ORR). Here, rare Earth element Y-doped Pd nanosponge (PdY NSs) are prepared by one-step reduction approach using NaBH4as reductant, which are employed for ORR under 0.1 M KOH. The PdY NSs with plentiful voids can offer a large number of active sites and improve the mass transfer for ORR. Moreover, the introduction of Y alters the electronic structure of Pd, thus promoting the dissociation and adsorption of oxygen. Therefore, the prepared PdY NSs display superior ORR activity and durability to the Pd NSs and Pd black, highlighting the introduction of rare Earth element on the enhancement of ORR performance for Pd-based catalysts.

6.
Nanotechnology ; 33(37)2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35653927

RESUMEN

Design of the structure, composition and interface of the catalysts is very important to improve oxygen reduction reaction (ORR) catalytic activity under alkaline environment. Herein, we propose a direct method to rapid synthesis of tannic acid (TA) modified PdAu alloy nanowires (PdAu@TA NWs). Compared with pure PdAu NWs and commercial Pt/C, the PdAu@TA NWs exhibit superior ORR electrocatalytic activity (mass activity: 0.73 A mg-1metaland specific activity: 3.50 mA cm-2), stability, and methanol tolerance in an alkaline medium because PdAu@TA NWs possess sufficient active sites and synergistic effect that can effectively promote the oxygen reduction, inhibit the oxidation of the catalyst and improve the methanol tolerance of the catalyst. This synthetic method is a promising strategy to prepare metallic catalyst with surface functionalization.

7.
Nanotechnology ; 34(5)2022 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-36240698

RESUMEN

The synthesis of catalysts with controllable morphology and composition is important to enhance the catalytic performance for oxygen reduction reaction (ORR). Herein, trimetallic PtPdY mesoporous nanospheres (PtPdY MNs) are produced via a one-step chemical reduction method applying F127 as soft temple under acidic condition. The mesoporous structure provides a large contact area and also stimulates the diffusion and mass transfer of reactants and products. Besides, synergistic effect among Pt, Pd and Y elements effectively alters their electronic structure, enhancing the catalytic activity. Therefore, the PtPdY MNs show excellent ORR permanence to Pt/C under the alkaline solution. This study offers an effective channel for the preparation of mesoporous metals with rare earth metal doping towards promising electrocatalytic applications.

8.
Chemistry ; 27(58): 14472-14477, 2021 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-34328663

RESUMEN

The optimization of structure and composition is essential to improve the performance of catalysts. Herein, mesoporous nanoparticles assembled PdNi/Ni nanotubes (mPdNi/Ni NTs) are successfully fabricated using nickel nanowires as sacrificial template. The combination of nanotubular structure with mesoporous nanoparticle morphology can provide facilitated transfer channels and sufficient active sites, allowing the full contact and reaction between catalysts and reactants. Therefore, the synthesized mPdNi/Ni NTs exhibite superior ethanol oxidation performance to mesoporous Pd nanotubes and commercial Pd black. This study proposes a rational strategy for the development of nanoparticle assembled nanotubes with surface mesoporous morphology, which can greatly improve catalytic performance in various electrocatalytic fields.

9.
Chemistry ; 26(11): 2493-2498, 2020 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-31867812

RESUMEN

Control of the composition and morphology of Pd-based electrocatalysts is a promising strategy for the development of efficient direct formic acid fuel cells. Herein, a two-step method is presented for the design of B-doped PdCuAu nanospine assemblies (B-PdCuAu NAs) using NaBH4 as the boron dopant. The boron content can be tailored easily by tuning the reaction time, and an optimal boron content is beneficial to promote the formic acid oxidation reaction. Such B-PdCuAu NAs exhibit superior mass and specific activities to commercial Pd black and PdCuAu NAs in alkaline solution. The excellent catalytic performance of B-PdCuAu NAs may arise from the increase in surface active sites and the electronic effect of boron modification. This work provides a facile synthesis of the B-doped metallic catalysts and highlights the boron modification in improving their performance as anode electrocatalysts for fuel cells.

10.
Nanotechnology ; 31(19): 195402, 2020 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-31978927

RESUMEN

It is highly desired but challenging to grow self-supporting zeolitic imidazolate framework (ZIF) derived carbon hybrids with well-aligned superstructures for various electrocatalytic applications. In this work, we present the controlled synthesis of ZIF-based carbon hybrid arrays using self-supporting NiCo2S4 nanotube arrays as self-sacrificing templates. Different from other reported carbon coated NiCo2S4 arrays with solid surfaces, the obtained NiCo2S4@NiCo/N-doped porous carbon array (NiCo2S4@NiCoNC/CC) have well-developed porous hollow structure and ultrafine NiCo nannoparticles deposited on the surface, which can provide facilitated channels and sufficient active sites for water electrolysis. The NiCo2S4@NiCoNC/CC exhibits superior catalytic performance for both hydrogen evolution reaction and oxygen evolution reaction with high efficiency in alkaline solution, achieving small overpotentials of 81 and 280 mV at the current density of 10 mA cm-2, respectively. Moreover, the NiCo2S4@NiCoNC/CC electrode shows excellent stability over 16 h of operation due to the robust structure of the electrode. The proposed strategy is highly promising for the rational design of well-aligned ZIF derived carbon hybrid arrays with desired morphology and composition on various substrates towards various electrocatalytic fields.

11.
Nanotechnology ; 31(4): 045401, 2020 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-31574496

RESUMEN

Tuning the compositions and morphologies of catalysts is very important for the design of efficient formic acid oxidation reaction (FAOR) electrocatalysts. Herein, unique PtPdP dendritic nanoparticles (PtPdP DNs) with uniform size and open-pore structure are fabricated by a facile method, in which the Pd and P elements are simultaneously incorporated into Pt DNs. The prepared PtPdP DNs show enhanced catalytic activity and stability for FAOR. The improved electrocatalytic activity toward FAOR for the PtPdP DNs is mainly attributed to the synergic enhancement effect of the structural and compositional advantages, which jointly promote the electrocatalytic kinetics and thus enhance the electrocatalytic performance.

12.
Chronic Dis Transl Med ; 10(2): 140-145, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38872765

RESUMEN

Background: Growth differentiation factor-15 (GDF-15) is a stress response protein and is related to cardiovascular diseases (CVD). This study aimed to investigate the association between GDF-15 and pre-eclampsia (PE). Method: The study involved 299 pregnant women, out of which 236 had normal pregnancies, while 63 participants had PE. Maternal serum levels of GDF-15 were measured by using enzyme-linked immunosorbent assay kits and then translated into multiple of median (MOM) to avoid the influence of gestational week at blood sampling. Logistic models were performed to estimate the association between GDF-15 MOM and PE, presenting as odd ratios (ORs) and 95% confidence intervals (CIs). Results: MOM of GDF-15 in PE participants was higher compared with controls (1.588 vs. 1.000, p < 0.001). In the logistic model, pregnant women with higher MOM of GDF-15 (>1) had a 4.74-fold (95% CI = 2.23-10.08, p < 0.001) increased risk of PE, adjusted by age, preconceptional body mass index, gravidity, and parity. Conclusions: These results demonstrated that higher levels of serum GDF-15 were associated with PE. GDF-15 may serve as a biomarker for diagnosing PE.

13.
Eur J Med Res ; 28(1): 56, 2023 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-36732824

RESUMEN

BACKGROUND: Several randomized clinical trials showed that aspirin could decrease the incidence of preeclampsia (PE) in women at high risk, but data from sources other than traditional clinical trials that investigating the preventive effect of aspirin 75 mg on PE is still lacking, especially in mainland China. We aimed to use Chinese real-world data to estimate the preventive effect of low-dose aspirin (LDA) on PE. METHODS: Clinical data of pregnant women who were at high risk of PE and had their first prenatal visit at the affiliated Taicang People's Hospital of Soochow University during November 31, 2018 and May 10, 2021 was retrospectively analyzed. Among the 266 included pregnant women, 115 individuals treated with aspirin 75 mg per day and the other 151 without such treatment were considered as the LDA group and the control group, respectively. RESULTS: In the LDA group, 64 (55.65%) of 115 pregnant women took aspirin before 16 weeks of gestation. Besides, 12 (10.43%) and 34 (22.52%) women developed PE in the LDA group and control group, respectively; the aspirin prophylaxis was associated with a lower risk of PE (odds ratio = 0.40, 95% confidence interval = 0.20-0.82, P = 0.0098). In addition, LDA is slightly more effective when initiated before 16 weeks of gestation or in those without chronic hypertension, when compared with their counterparts. CONCLUSION: Prophylaxis with 75 mg per day of aspirin in high-risk women resulted in a significantly lower incidence of PE than that in the control group.


Asunto(s)
Preeclampsia , Femenino , Embarazo , Humanos , Masculino , Preeclampsia/epidemiología , Preeclampsia/prevención & control , Preeclampsia/tratamiento farmacológico , Estudios Retrospectivos , Embarazo de Alto Riesgo , Aspirina/uso terapéutico , Primer Trimestre del Embarazo
14.
Chem Commun (Camb) ; 59(74): 11101-11104, 2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37644828

RESUMEN

Herein, we propose nitrogen (N)-intercalated Pd metallene nanoribbons (N-Pd MNRs), which exhibit favorable and stable oxygen reduction reaction (ORR) performance in alkaline media. The ultrathin configuration of the N-Pd MNRs exposes more atoms, thus acting as active sites. More importantly, N intercalation triggers electronic interaction between Pd and N to establish Pd-N bonds and induces lattice strain, which optimizes the electronic structure of the metallene nanoribbons, thereby modulating the binding strength between the intermediates and active sites. This work offers new insights into the rational design of N intercalated metallene nanoribbons for efficient ORR catalysis.

15.
Front Endocrinol (Lausanne) ; 14: 1084896, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36742413

RESUMEN

Objective: Gestational diabetes mellitus (GDM) is a common glucose metabolism disease occurs in pregnancy that affects both maternal and neonatal health. Recently, increasing studies have attached importance to the relationship between growth differentiation factor 15 (GDF-15) and GDM, but the results were inconclusive. Therefore, we conducted a meta-analysis to examine the association between GDF-15 and GDM. Materials and methods: A systematical search was performed in Gene Expression Omnibus (GEO), PubMed and Google Scholar till Oct 27, 2022. We first calculated the mean and standard deviation of GDF-15 expression levels from the included eligible datasets and articles. Then, a meta-analysis was conducted to depict the difference in GDF-15 mRNA or GDF-15 protein expression between case and control groups by using conservative random effect model. Moreover, the potential publication bias was checked with the aid of Begg's test and Egger's test. Finally, sensitivity analyses were performed by changing the inclusion criteria. Results: In summary, 12 GEO datasets and 5 articles were enrolled in our study, including 789 GDM patients and 1202 non-GDM pregnant women. It was found that the expression levels of GDF-15 mRNA and GDF-15 protein in late pregnancy were significantly higher in GDM patients compared with non-GDM pregnant women, with the standard mean difference (SMD) and 95% confidence interval (95% CI) of 0.48 (0.14, 0.83) and 0.82 (0.32-1.33), respectively. Meanwhile, a slightly weakened association between GDF-15 protein levels and GDM was also observed in the middle pregnancy, with SMD (95% CI) of 0.53 (0.04-1.02). Conclusion: In all, our results suggested that the expression levels of GDF-15 were significantly higher in GDM patients compared with non-GDM pregnant women, especially in the late pregnancy.


Asunto(s)
Diabetes Gestacional , Femenino , Humanos , Embarazo , Diabetes Gestacional/genética , Glucosa , Factor 15 de Diferenciación de Crecimiento/genética , ARN Mensajero/genética
16.
Nanoscale ; 14(34): 12332-12338, 2022 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-35969200

RESUMEN

The electrochemical reduction of nitrate to ammonia provides a green and delocalized route for ammonia synthesis under ambient conditions, which requires advanced catalysts with high activity and selectivity. In this work, we propose a two-step conversion strategy to construct hierarchical copper nanosheet-based Cu nanotubes using pre-synthesized Cu nanowires as the starting material for the electrocatalytic nitrate reduction reaction (NO3RR). The conversion of Cu nanowires into Cu nanotubes could be realized through chemical oxidation followed by in situ electrochemical reduction, enabling the effective engineering of active sites and thus boosting the electrocatalytic nitrate-to-ammonia capability. Such a controllable reconstruction strategy provides a new avenue for constructing high-performance electrocatalysts for sustainable NH3 synthesis and the elimination of NO3- contamination.

17.
ACS Appl Mater Interfaces ; 13(26): 30479-30485, 2021 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-34160205

RESUMEN

Electrochemical water splitting is one hopeful strategy for hydrogen production, and designing efficient hydrogen evolution electrocatalysts under universal pH is one of the most critical topics. Here, we have successfully prepared mesoporous bimetallic core-shell nanostructures with Au nanowires (Au NWs) as cores and mesoporous Rh as shells (Au@mRh NWs). Due to the one-dimensional structure and mesoporous core-shell structure, Au@mRh NWs possess more active sites and provide the synergistic effect, leading to the great improvement of the electrochemical activity toward the hydrogen evolution reaction under a wide range of pH. The present work proposes a versatile strategy for preparing a bimetallic core-shell structure with a mesoporous shell, which is highly promising for more electrocatalytic applications.

18.
ACS Appl Mater Interfaces ; 13(17): 20233-20239, 2021 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-33884861

RESUMEN

Designing one-dimensional (1D) bimetallic nanomaterials is of great significance for electrochemical nitrogen fixation. Inspired by this, 1D AuPd nanospikes (AuPd NSs) composed with internal Au nanowire and external Pd nanohumps were fabricated by a flexible low-temperature wet-chemical method. Benefiting from the excellent electron transport efficiency of the 1D material and the accessible surface area provided by the unique nanospike-like structure, AuPd NSs exhibit outstanding nitrogen reduction reaction performance with an NH3 yield rate of 16.9 µg h-1 mg-1cat. and a Faradaic efficiency of 15.9% at -0.3 V under 0.1 M Na2SO4. This work not only provides an effective electrocatalyst for nitrogen fixation technology, but also presents a flexible method for the controlled synthesis of spike-like nanomaterials.

19.
Nanoscale ; 13(5): 3208-3213, 2021 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-33528487

RESUMEN

The design of bimetallic core-shell nanostructures with mesoporous surfaces is considered significant to strengthen the catalytic activity and stability for direct methanol fuel cells. Here, we report a flexible method to synthesize Au@Pd core-shell mesoporous nanoflowers (Au@mPd NFs) with Au core coated with mesoporous Pd nano-petals, in which polymeric micelle-assembled structures are used as templates to induce the formation of mesopores. Benefiting from the electronic and structural effects, Au@mPd NFs show excellent electrocatalytic activity and stability for methanol oxidation reaction in alkaline electrolytes. This study demonstrates a versatile strategy for the fabrication of core-shell mesoporous nanoflowers with adjustable composition.

20.
Nanoscale ; 12(37): 19159-19164, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32944727

RESUMEN

Adjusting the morphology and composition of Pd-based materials is a promising strategy to improve their performance for the electrocatalytic formic acid oxidation reaction (FAOR). In this work, we report the preparation of B-doped PdRu nanopillar assemblies (B-PdRu NPAs) by a two-step method using NaBH4 as the boron dopant. On combining the hyper-branched structure and the multi-component synergistic effect, B-PdRu NPAs achieve a high mass activity of 1.09 mA µg-1Pd for the FAOR and retain 73.19% of the initial activity after 500 cycles, which is superior to undoped counterparts. The proposed synthesis strategy provides a simple method for the synthesis of metal-nonmetal nanomaterials with desired composition and design structure for electrocatalytic fields.

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