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1.
Chemphyschem ; 25(17): e202300966, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-38787917

RESUMO

The ongoing advancements in lithium-ion battery technology are pivotal in propelling the performance of modern electronic devices and electric vehicles. Amongst various components, the cathode material significantly influences the battery performance, such as the specific capacity, capacity retention and the rate performance. Ternary cathode materials, composed of nickel, manganese, and cobalt (NCM), offer a balanced combination of these traits. Recent developments focus on elemental doping, which involves substituting a fraction of NCM constituent ions with alternative cations such as aluminum, titanium, or magnesium. This strategic substitution aims to enhance structural stability, increase capacity retention, and improve resistance to thermal runaway. Doped ternary materials have shown promising results, with improvements in cycle life and operational safety. However, the quest for optimal doping elements and concentrations persists to maximize performance while minimizing cost and environmental impact, ensuring the progression towards high-energy-density, durable, and safe battery technologies.

2.
BMC Plant Biol ; 23(1): 289, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37254044

RESUMO

BACKGROUND: Sphagneticola trilobata (L.) Pruski is a prevalent and widely distributed invasive plant in South China. To investigate the molecular mechanisms underlying its rapid adaptation, we employed DNA methylation-sensitive amplified polymorphism (MSAP) and simple sequence repeat (SSR) analysis to study 60 S. trilobata individuals collected from Fuzhou (FZ), Haikou (HK), Jinghong (JH) and Guangzhou (GZ). RESULTS: In this study, we computed the Shannon diversity index (I) of SSR and MSAP as 0.354 and 0.303, respectively. The UPGMA phylogenetic tree and PCoA analyses showed that MSAP had a better discriminatory power to distinguish populations from different regions. Notably, the GZ population was found to be the most distinct from the other three populations. Moreover, Mantel analysis revealed a significantly higher correlation between epigenetic distance and geographic distance as compared to genetic distance and geographic distance. Consequently, the correlation between epigenetic distance and geographic distance observed to be markedly stronger than that between genetic distance and geographical distance on Mantel analysis. CONCLUSIONS: The S. trilobata populations in various regions displayed a high of complementary genetic and epigenetic diversity, which was a key feature contributing to their rapid invasion. Interestingly, the correlation between epigenetics and geographical distance was significantly stronger than that observed for genetics and geographical distance. These findings indicated that the epigenetic mechanism of S. trilobar exhibited high plasticity, leading to significant differences in methylation pattern across different populations.


Assuntos
Asteraceae , Polimorfismo Genético , Filogenia , Epigênese Genética , Metilação de DNA/genética , China , Variação Genética
3.
Small ; 19(18): e2207619, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36775918

RESUMO

Al ion batteries (AIBs) are attracting considerable attention owing to high volumetric capacity, low cost, and high safety. However, the strong electrostatic interaction between Al3+ and host lattice leads to discontented cycling life and inferior rate capability. Herein, a new strategy of employing water molecules contained VOPO4 ·H2 O to boost Al3+ migration via the charge shielding effect of water is reported. It is revealed that VOPO4 ·H2 O with water lubrication effect and smaller steric hindrance owns high capacity and fast Al3+ diffusion, while the loss of unstable water upon cycling leads to a rapid performance degradation. To address this problem, ultrathin VOPO4 ·H2 O@MXene nanosheets are fabricated via the formed TiOV bond between VOPO4 ·H2 O and MXene. The MXene aided exfoliation results in enhanced VOwater bond strength between H2 O and VOPO4 that endows the obtained composite with strong water holding ability, contributing to the extraordinary cycling stability. Consequently, the VOPO4 ·H2 O@MXene delivers a high discharge potential of 1.8 V and maintains discharge capacities of 410 and 374.8 mAh g-1 after 420 and 2000 cycles at the current densities of 0.5 and 1.0 A g-1 , respectively. This work provides a new understanding of water-contained AIBs cathodes and vital guidance for developing high-performance AIBs.

4.
Analyst ; 140(9): 3183-92, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-25756085

RESUMO

Porous bimetallic alloyed palladium silver (PdAg) nanoflowers supported on reduced graphene oxide (PdAg NFs/rGO) were prepared via a facile and simple in situ reduction process, with the assistance of cetyltrimethylammonium bromide as a structure directing agent. The as-prepared nanocomposite modified glassy carbon electrode (PdAg NFs/rGO/GCE) showed enhanced catalytic currents and enlarged peak potential separations for the oxidation of ascorbic acid (AA), dopamine (DA), and uric acid (UA) as compared to those of PdAg/GCE, rGO/GCE, commercial Pd/C/GCE, and bare GCE. The as-developed sensor can selectively detect AA, DA, and UA with a good anti-interference ability, wide concentration ranges of 1.0 µM-2.1 mM, 0.4-96.0 µM, and 1.0-150.0 µM, respectively, together with low detection limits of 0.057, 0.048, and 0.081 µM (S/N = 3), respectively. For simultaneous detection of AA, DA, and UA, the linear current-concentration responses were observed from 1.0 µM-4.1 mM, 0.05-112.0 µM, and 3.0-186.0 µM, with the detection limits of 0.185, 0.017, and 0.654 µM (S/N = 3), respectively.


Assuntos
Ácido Ascórbico/análise , Dopamina/análise , Grafite/química , Nanoestruturas/química , Prata/química , Ácido Úrico/análise , Ligas/química , Técnicas Biossensoriais/instrumentação , Técnicas Eletroquímicas/instrumentação , Eletrodos , Limite de Detecção , Nanoestruturas/ultraestrutura , Oxirredução , Óxidos/química , Paládio/química , Porosidade
5.
Small Methods ; : e2401000, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39212650

RESUMO

Nonaqueous aluminum-ion batteries (AIBs) provide advantages, such as high energy density, enhanced safety, and reduced corrosion, making them ideal for advanced energy storage solutions. A key challenge faced by AIBs is the lack of suitable cathode materials for rapid Al-ion insertion /extraction. Herein, K2Mn[Fe(CN)6] 2H2O (KMHCF) is innovatively chosen as a model to investigate the aluminum storage performance of Prussian blue analogues in nonaqueous AIBs. As anticipated, the KMHCF allows for reversible aluminum storage and exhibits characteristic charge/discharge plateaus. Furthermore, carbon combined highly crystalline KMHCF (HC-KMHCF@C) is synthesized through a chelator-assisted preparation method in combination with an in situ carbon compositing technique. With reduced [Fe(CN)6]4⁻ defects, lower interstitial water content, and enhanced conductivity, HC-KMHCF@C exhibits a high aluminum storage capacity (146.2 mAh g⁻¹ at 0.5 A g⁻¹) and satisfactory cycling performance (maintaining 86.4 mAh g⁻¹ after 800 cycles). The electrochemical reaction mechanism of HC-KMHCF@C is investigated in detail. During the initial charge, K⁺ ions are extracted, shifting the structure from monoclinic to cubic. In subsequent cycles, reversible Al3+ insertion and extraction cause the structure to alternate between monoclinic and cubic phases.

6.
Org Biomol Chem ; 10(8): 1602-11, 2012 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-22228267

RESUMO

A mild and efficient Cu(2)O-catalyzed domino intramolecular C-N coupling/C-Y (Y = O, S, N) bond formation was successfully achieved. Thus oxazino[3,2-a]indole, thiazino[3,2-a]indole and indolo[2,1-b]quinazoline derivatives were facilely assembled from readily accessible gem-dibromovinyl systems. The protocol is general and practical, affording a variety of the indole-incorporated products in good to excellent yields even under air atmosphere.


Assuntos
Cobre/química , Indóis/química , Compostos Policíclicos/química , Catálise , Ciclização , Imidazóis/química , Estrutura Molecular
7.
ACS Appl Mater Interfaces ; 14(6): 8076-8085, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35112859

RESUMO

Rechargeable aluminum-ion batteries (AIBs), using low-cost and inherent safety Al metal anodes, are regarded as promising energy storage devices next to lithium-ion batteries. Currently, one of the greatest challenges for AIBs is to explore cathodes suitable for feasible Al3+ insertion/extraction with high structure stability. Herein, a facile co-engineering on solid solution phase and cavity structure is developed via Prussian blue analogues by a simple and facile sulfidation strategy. The obtained uniform yolk-shell Fe0.4Co0.6S@N-doped carbon nanocages (y-s Fe0.4Co0.6S@NC) display a high reversible capacity of 141.3 mA h g-1 at 500 mA g-1 after 100 cycles and a good rate capability of 100.9 mA h g-1 at 1000 mA g-1. The improved performance can be mainly ascribed to the dual merits of the composite; that is, more negative Al3+ formation energy and improved Al3+ diffusion kinetics favored by the solid solution phase and Al3+ insertion/extraction accommodable space stemmed from the yolk-shell structure. Moreover, the reaction mechanism study discloses that the reaction involves the intercalation of Al3+ ions into Fe0.4Co0.6S to generate AllFemConS and elemental Fe and Co.

8.
Nanoscale ; 6(11): 5708-13, 2014 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-24791275

RESUMO

A simple and facile method is developed for one-pot preparation of hierarchical dendritic PtPd nanogarlands supported on reduced graphene oxide (PtPd/RGO) at room temperature, without using any seed, organic solvent, or complex apparatus. It is found that octylphenoxypolyethoxyethanol (NP-40) as a soft template and its amount are critical to the formation of PtPd garlands. The as-prepared nanocomposites are further applied to methanol and ethanol oxidation with significantly enhanced electrocatalytic activity and better stability in alkaline media.

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