Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Molecules ; 29(13)2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38999033

RESUMEN

The design of cheap, noble-metal-free, and efficient electrocatalysts for an enhanced hydrogen evolution reaction (HER) to produce hydrogen gas as an energy source from water splitting is an ideal approach. Herein, we report the synthesis of Fe2O3 nanorods-NiFe2O4 nanoparticles on cotton fiber cloth (Fe2O3-NiFe2O4/CF) at a low temperature as an efficient electrocatalyst for HERs. Among the as-prepared samples, the optimal Fe2O3-NiFe2O4/CF-3 electrocatalyst exhibits good HER performance with an overpotential of 127 mV at a current density of 10 mA cm-2, small Tafel slope of 44.9 mV dec-1, and good stability in 1 M KOH alkaline solution. The synergistic effect between Fe2O3 nanorods and NiFe2O4 nanoparticles of the heterojunction composite at the heterointerface is mainly responsible for improved HER performance. The CF is an effective substrate for the growth of the Fe2O3-NiFe2O4 nanocomposite and provides conductive channels for the active materials' HER process.

2.
Environ Sci Pollut Res Int ; 31(26): 37923-37942, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38769264

RESUMEN

Neonicotinoids, as the fastest-growing class of insecticides, currently account for over 25% of the global pesticide market. Their effectiveness in controlling a wide range of pests that pose a threat to croplands, home yards/gardens, and golf course greens cannot be denied. However, the extensive use of neonicotinoids has resulted in significant declines in nontarget organisms such as pollinators, insects, and birds. Furthermore, the potential chronic, sublethal effects of these compounds on human health remain largely unknown. To address these pressing issues, it is crucial to explore and understand the capabilities of electrochemical sensors in detecting neonicotinoid residues. Surprisingly, despite the increasing importance of this topic, no comprehensive review article currently exists in the literature. Therefore, our proposed review aims to bridge this gap by providing a thorough analysis of the use of electrochemical methods for neonicotinoid determination. In this review article, we will delve into various aspects of electrochemical analysis, including the influence of electrode materials, employed techniques, and the different types of electrode mechanisms utilized. By synthesizing and analysing the existing research in this field, our review will offer valuable insights and guidance to researchers, scientists, and policymakers alike.


Asunto(s)
Insecticidas , Neonicotinoides , Neonicotinoides/análisis , Insecticidas/análisis , Técnicas Electroquímicas , Monitoreo del Ambiente/métodos , Animales
3.
Microorganisms ; 11(10)2023 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-37894202

RESUMEN

Nanoparticles have emerged as a prominent area of research in recent times, and silver nanoparticles (AgNPs) synthesized via phyco-technology have gained significant attention due to their potential therapeutic applications. Nodularia haraviana, a unique and lesser-explored cyanobacterial strain, holds substantial promise as a novel candidate for synthesizing nanoparticles. This noticeable research gap underscores the novelty and untapped potential of Nodularia haraviana in applied nanotechnology. A range of analytical techniques, including UV-vis spectral analysis, dynamic light scattering spectroscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray powder diffraction, were used to investigate and characterize the AgNPs. Successful synthesis of AgNPs was confirmed through UV-visible spectroscopy, which showed a surface plasmon resonance peak at 428 nm. The crystalline size of AgNPs was 24.1 nm. Dynamic light scattering analysis revealed that silver oxide nanoparticles had 179.3 nm diameters and a negative surface charge of -18 mV. Comprehensive in vitro pharmacogenetic properties revealed that AgNPs have significant therapeutic potential. The antimicrobial properties of AgNPs were evaluated by determining the minimum inhibitory concentration against various microbial strains. Dose-dependent cytotoxicity assays were performed on Leishmanial promastigotes (IC50: 18.71 µgmL-1), amastigotes (IC50: 38.6 µgmL-1), and brine shrimps (IC50: 134.1 µg mL-1) using various concentrations of AgNPs. The findings of this study revealed that AgNPs had significant antioxidant results (DPPH: 57.5%, TRP: 55.4%, TAC: 61%) and enzyme inhibition potential against protein kinase (ZOI: 17.11 mm) and alpha-amylase (25.3%). Furthermore, biocompatibility tests were performed against macrophages (IC50: >395 µg mL-1) and human RBCs (IC50: 2124 µg mL-1). This study showed that phyco-synthesized AgNPs were less toxic and could be used in multiple biological applications, including drug design and in the pharmaceutical and biomedical industries. This study offers valuable insights and paves the way for further advancements in AgNPs research.

4.
Materials (Basel) ; 16(7)2023 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-37048850

RESUMEN

Currently, transition metal dichalcogenides-based alkaline metal ion batteries have been extensively investigated for renewable energy applications to overcome the energy crisis and environmental pollution. The layered morphologys with a large surface area favors high electrochemical properties. Thermal stability, mechanical structural stability, and high conductivity are the primary features of layered transition metal dichalcogenides (L-TMDs). L-TMDs are used as battery materials and as supporters for other active materials. However, these materials still face aggregation, which reduces their applicability in batteries. In this review, a comprehensive study has been undertaken on recent advancements in L-TMDs-based materials, including 0D, 1D, 2D, 3D, and other carbon materials. Types of structural engineering, such as interlayer spacing, surface defects, phase control, heteroatom doping, and alloying, have been summarized. The synthetic strategy of structural engineering and its effects have been deeply discussed. Lithium- and sodium-ion battery applications have been summarized in this study. This is the first review article to summarize different morphology-based TMDs with their intrinsic properties for alkali metal ion batteries (AMIBs), so it is believed that this review article will improve overall knowledge of TMDs for AMIBS applications.

5.
Dalton Trans ; 49(44): 15682-15692, 2020 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-33124630

RESUMEN

The synthesis of competitive, affordable and sustainable electrocatalysts via simple and scalable methods is highly desirable for the oxygen evolution reaction (OER). Usually, expensive, complex, time-consuming methods are applied to prepared suitable electrocatalysts for the OER. In contrast, a single-step thermal method is simple and inexpensive. Nickel and iron-based composite materials are potential candidates as OER catalysts. Accordingly, herein, Se-doped Fe2O3-decorated Ni/NiO particles on carbon cloth (Se-Fe2O3@Ni/NiO/CC) were synthesized via a facile and scalable one-step thermal method. The individual Se-Fe2O3@Ni/NiO particles were accommodated in holes in the carbon fibers of CC. The optimized Se-Fe2O3@Ni/NiO/CC-2 sample exhibited an outstanding OER performance with an overpotential of 205 mV at the current density 10 mA cm-2, small Tafel slope of 36 mV dec-1, and good stability in 1.0 M KOH electrolyte. The outstanding catalytic performance was mainly attributed to the heterointerfaces between Se-Fe2O3 and Se-Ni/NiO. Moreover, the accommodation of the Se-Fe2O3@Ni/NiO particles in the holes of CC restricted the aggregation of the particles, and CC provided a conductive substrate for the OER process. Thus, this work provides a simple, scalable and effective strategy for designing and engineering of outstanding electrocatalysts for the OER.

6.
Nanoscale ; 10(20): 9698-9706, 2018 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-29762620

RESUMEN

Low-cost electrocatalysts play an important role in the hydrogen evolution reaction (HER). Particularly, transition metal phosphides (TMPs) are widely applied in the development of HER electrocatalysts. To improve the poor electrochemical reaction kinetics of HER, we introduce a facile way to synthesize carbon core-shell materials containing cobalt phosphide nanoparticles embedded in different graphene aerogels (GAs) (CoP@C-NPs/GA-x (x = 5, 10 and 20)) using seaweed biomass as precursors. The synthesized CoP@C-NPs/GA-5 exhibits efficient catalytic activity with small overpotentials of 120 and 225 mV at current densities of 10 mA cm-2, along with the low Tafel slopes of 57 and 66 mV dec-1, for HER in acidic and alkaline electrolytes, respectively. Compared with carbon aerogel (CA) containing cobalt phosphide nanoparticles (CoP-NPs@CA), the stability of CoP@C-NPs/GA-5 coated with carbon-shells (∼0.8 nm) was significantly improved in acidic electrolytes. We also prepared carbon core-shell materials containing nickel phosphide nanoparticles embedded in GA (Ni2P@C-NPs/GA) to further expand this synthetic route. The graphene-Ni2P@C aerogel shows a similar morphology and better catalytic activity for HER in acidic and alkaline electrolytes. In this work, the robust three-dimensional (3D) GA matrix with abundant open pores and large surface area provides unblocked channels for electrolyte contact and electronic transfer and enables very close contact between the catalyst and electrolyte. The MxP@C core-shell structure prevents the inactivation of MxP NPs during HER processes, and the thin graphene oxide (GO) layers and 3D CA together build up a 3D conductive matrix, which not only adjusts the volume expansion of MxP NPs as well as preventing their aggregation, but also provides a 3D conductive pathway for rapid charge transfer processes. The present synthetic strategy for phosphides via in situ phosphorization with 3D GA can be extended to other novel high-performance catalysts. The simple synthesis and efficient catalytic activity of MXP@C-NPs/GA indicate good application prospects in HER.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA