Search Results (78)

Cyclodextrins in metal oxide nanoparticles (NPs) serve as stabilizing, dispersing, and functionalizing agents that enhance antimicrobial performance through better nanoparticle stability, synergistic action, and potential controlled release mechanisms, making them ideal for advanced biomedical and environmental antimicrobial applications. In this study, NPs of vanadium pentoxide (V₂O₅) were obtained by the precipitation method, and, following a supramolecular assembly, were synthesized using the impregnation method via addition of β-cyclodextrin (BCD) and its derivatives, such as hydroxypropyl-β-cyclodextrin (HCD) and methyl-β-cyclodextrin (MCD). The formation of the V₂O₅:CDs was driven by non-covalent host–guest interactions, leading to a stable supramolecular structure with enhanced physicochemical properties. Morphological analysis using scanning electron microscopy (SEM) revealed uniformly distributed V₂O₅ NPs within the CD matrix. Structural characterization was further supported by proton nuclear magnetic resonance (NMR) spectroscopy, which confirmed the inclusion interactions between V₂O₅ and CDs. The synthesized NPs demonstrated significant antimicrobial activity against Gram-positive and fungal strains, indicating a synergistic enhancement in bioactivity due to the supramolecular architecture. This work highlights the potential of CD-assisted V₂O₅ NPs as promising antimicrobial agents for biomedical and environmental applications. Full article

Layered intercalating V₂O₅ (vanadium pentoxide) is a durable battery-type electrode material exploited in supercapacitors. The advancement of V₂O₅ nanomaterials synthesized from non-aqueous organic solvents holds significant potential for energy storage applications. Liquid-phase synthesis of orthorhombic V₂O₅ cathode material corroborated its compatibility with quartet glycols and allowed examination of their explicit roles in faradic charge storage efficacy. V₂O₅ was found to be an intercalative material in all the quartet glycols. The crystalline, rod-like morphology and monodisperse V₂O₅ electrode were ascribed to the effects of ethylene, diethylene, triethylene, and tetraethylene glycols. Notable differences were observed in the electrochemical analysis of the prepared V₂O₅ (EV, DV, TV, and TTV). In a three-electrode cell setup, the DV electrode demonstrated a superior specific capacity of 460.2 C/g at a current density of 1 A/g. From the Trasatti analysis, the DV electrode exhibited 961.53 C/g of total capacitance, comprising a diffusion-controlled contribution of 898.19 C/g and a surface-controlled contribution of 63.34 C/g. The aqueous asymmetric device DV//AC exhibited a maximum energy density of 65.72 Wh/kg at a power density of 1199.97 W/kg. The glycol-derived electrodes were anticipated to bepromising materials for supercapacitors and have the potential to meet electrochemical energy needs. Full article

Vanadium pentoxide (V₂O₅) has attracted considerable interest owing to its unique chemical and physical properties. However, traditional synthesis methods are often time-consuming, complex, and difficult to scale, limiting the broader applications of V₂O₅. Herein, we present a flame vapor deposition (FVD) method to enable rapid, scalable, and one-step synthesis of various V₂O₅ nanostructures under ambient pressure conditions. By optimizing critical synthesis parameters, specifically, source temperature (840 °C) and substrate temperature (610 °C), we achieved highly crystalline, one-dimensional (1D) V₂O₅ nanorods on a variety of substrates, including silicon (Si), fluorine tin doped (FTO) glass, stainless steel, and silicon dioxide (SiO₂). Moreover, we demonstrate the rapid growth of ultrathin, two-dimensional (2D) V₂O₅ nanoflakes with nanometer-scale thickness, as well as enhanced uniformity and coverage density with an externally applied electric field. This FVD method provides a simple, efficient, and scalable approach for synthesizing advanced V₂O₅ nanostructures, significantly expanding opportunities for their integration into various technological applications. Full article

This study reports an efficient and low-cost hydrothermal method for synthesizing vanadium oxide/graphene nanocatalysts. Field-emission scanning electron microscopy (FESEM) revealed the formation of nanostructured catalysts with consistent and directional shapes, as confirmed by X-ray diffraction (XRD). Fourier transform infrared (FTIR) spectroscopy indicated the presence of V₂O₅ and graphene, highlighting their bonds and structures. Thermogravimetric analysis (TGA) identified three stages of weight loss in the nanocatalysts, corresponding to water molecule evaporation, decomposition of residual organics, and the formation of yellow vanadium pentoxide particles due to the oxidation of vanadium V⁴⁺. Gas chromatography analysis from 450 °C to 600 °C showed that ethylene selectivity increased with temperature, while propylene selectivity showed the opposite trend. The effectiveness of these nanocatalysts was assessed in the oxidative dehydrogenation of propane using temperature programmed reduction. The approach of graphene-based vanadium oxide nanostructures will open up a new insight into the fabrication of high-performance catalysts. Full article

We report a gas-phase precursor modulation strategy for the controlled synthesis of 1T-phase vanadium diselenide (VSe₂) from vanadium pentoxide (V₂O₅) nanosheets by systematically adjusting the vapor pressure of selenium. By controlling the selenium vapor pressure, selenium-free vapor transport of vanadium dioxide led to the spontaneous oxidation and formation of tens-of-micrometer-sized rectangular V₂O₅ crystals, while moderate selenium introduction produced intermediate oxygen-rich phases with trapezoidal crystal facets, and a highly selenium-rich environment yielded trigonal VSe₂ crystals. Raman scattering measurements confirmed the stepwise transformation from V₂O₅ to VSe₂, and atomic force microscopy revealed well-defined layered morphologies and distinct conformation within an atomically thin regime. Additionally, high-resolution transmission electron microscopy validated the orthorhombic and trigonal crystal structures of V₂O₅ and VSe₂, respectively. This work demonstrates the versatility of fine-tuned vapor-phase growth conditions in vanadium-based layered compounds, providing useful platforms to optimize structural composition with atomic precision. Full article

In this study, vanadium (3.5⁺) electrolyte was prepared for vanadium redox flow batteries (VRFBs) through a reduction reaction using a batch-type hydrothermal reactor, differing from conventional production methods that utilize VOSO₄ and V₂O_5. The starting material, V₂O₅, was mixed with various concentrations (0.8 M, 1.2 M, 1.6 M, 2.0 M) of citric acid (CA) as the reducing agent and stirred for 60 min at 90 °C using a hot plate to ensure complete dispersion in the solution. The resulting solution was subsequently subjected to a hydrothermal reduction reaction (HRR) furnace at 150 °C for 24 h to generate vanadium (3.5⁺). The mixed states of the produced vanadium (3⁺) and vanadium (4⁺) were confirmed using UV-vis spectroscopy. The electrochemical properties of the electrolyte were investigated through cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), revealing that the optimal concentration of the CA was 1.6 M. The current efficiency, energy efficiency, and voltage efficiency of the electrolyte produced via the HRR process was compared with that prepared using VOSO₄ in charge and discharge experiments. The results demonstrate that the HRR process yields an enhanced electrolyte across all efficiency metrics produced through the given improved performance in all efficiencies. These findings indicate that the HRR process using citric acid can facilitate the straightforward preparation of vanadium (3.5⁺) electrolyte, making it suitable for large-scale production. Full article

Incorporating metal cations into V₂O₅ has been proven to be an effective method for solving the poor long-term cycling performance of vanadium-based oxides as electrodes for mono- or multivalent aqueous rechargeable batteries. This is due to the existence of a bilayer structure with a large interlayer space in the V₂O₅ electrode and to the fact that the intercalated ions act as pillars to support the layered structure and facilitate the diffusion of charged carriers. However, a fundamental understanding of the mechanical stability of multi-ion-co-intercalated bilayered V₂O₅ is still lacking. In this paper, a variety of pillared vanadium pentoxides with two types of co-intercalated ions were studied. The root-mean-square deviation of the V-O bonds and the elastic constants calculated by density functional theory were used as references to evaluate the stability of the intercalated compounds. The d-band center and electronic band structures are also discussed. Our theoretical results show that the structural characteristics and stability of the system are quite strongly influenced by the intercalating strategy. Full article

Aqueous zinc-ion batteries (ZIBs) have attracted burgeoning attention and emerged as prospective alternatives for scalable energy storage applications due to their unique merits such as high volumetric capacity, low cost, environmentally friendly, and reliable safety. Nevertheless, current ZIBs still suffer from some thorny issues, including low intrinsic electron conductivity, poor reversibility, zinc anode dendrites, and side reactions. Herein, conductive polyaniline (PANI) is intercalated as a pillar into the hydrated V₂O₅ (PAVO) to stabilize the structure of the cathode material. Meanwhile, graphene oxide (GO) was modified onto the glass fiber (GF) membrane through simple electrospinning and laser reduction methods to inhibit dendrite growth. As a result, the prepared cells present excellent electrochemical performance with enhanced specific capacity (362 mAh g⁻¹ at 0.1 A g⁻¹), significant rate capability (280 mAh g⁻¹ at 10 A g⁻¹), and admirable cycling stability (74% capacity retention after 4800 cycles at 5 A g⁻¹). These findings provide key insights into the development of high-performance zinc-ion batteries. Full article

Sodium-ion batteries (SIBs) have emerged as a promising alternative to lithium-ion batteries (LIBs) in sectors requiring extensive energy storage. The abundant availability of sodium at a low cost addresses concerns associated with lithium, such as environmental contamination and limited availability. However, SIBs exhibit lower energy density and cyclic stability compared to LIBs. One of the key challenges in improving the performance of SIBs lies in the electrochemical properties of the cathode materials. Among the various cathodes utilized in SIBs, sodium vanadium phosphates (NVPs) and sodium vanadium fluorophosphates (NVPFs) are particularly advantageous. These vanadium-based cathodes offer high theoretical capacity and are cost-effective. Commercialization of SIBs with NVPF cathodes has already begun. However, the poor conductivity of these cathode materials leads to a short cycle life and inferior rate performance. Various synthesis methods have been explored to enhance the conductivity, including heteroatom doping (N, S, and Co), surface modification, the fabrication of porous nanostructures, and composite formation with conductive carbon materials. In particular, cathodes with interconnected hierarchical micro- and nano-porous morphologies have shown promise. This review focuses on the diverse synthesis methods reported for preparing hierarchically porous cathodes. With increased attention, particular emphasis has been placed on carbon composites of NVPs and NVPFs. Additionally, the synthesis of vanadium pentoxide-based cathodes is also discussed. Full article

Chronic environmental exposure to toxic heavy metals, which often occurs as a mixture through occupational and industrial sources, has been implicated in various neurological disorders, including Parkinsonism. Vanadium pentoxide (V₂O₅) typically presents along with manganese (Mn), especially in welding rods and high-capacity batteries, including electric vehicle batteries; however, the neurotoxic effects of vanadium (V) and Mn co-exposure are largely unknown. In this study, we investigated the neurotoxic impact of MnCl₂, V₂O_5, and MnCl₂-V₂O₅ co-exposure in an animal model. C57BL/6 mice were intranasally administered either de-ionized water (vehicle), MnCl₂ (252 µg) alone, V₂O₅ (182 µg) alone, or a mixture of MnCl₂ (252 µg) and V₂O₅ (182 µg) three times a week for up to one month. Following exposure, we performed behavioral, neurochemical, and histological studies. Our results revealed dramatic decreases in olfactory bulb (OB) weight and levels of tyrosine hydroxylase, dopamine, and 3,4-dihydroxyphenylacetic acid in the treatment groups compared to the control group, with the Mn/V co-treatment group producing the most significant changes. Interestingly, increased levels of α-synuclein expression were observed in the substantia nigra (SN) of treated animals. Additionally, treatment groups exhibited locomotor deficits and olfactory dysfunction, with the co-treatment group producing the most severe deficits. The treatment groups exhibited increased levels of the oxidative stress marker 4-hydroxynonenal in the striatum and SN, as well as the upregulation of the pro-apoptotic protein PKCδ and accumulation of glomerular astroglia in the OB. The co-exposure of animals to Mn/V resulted in higher levels of these metals compared to other treatment groups. Taken together, our results suggest that co-exposure to Mn/V can adversely affect the olfactory and nigral systems. These results highlight the possible role of environmental metal mixtures in the etiology of Parkinsonism. Full article

The fabrication of sponge-like vanadium pentoxide (V₂O₅) nanostructures using vertically aligned carbon nanotubes (VACNTs) as a template is presented. The VACNTs were grown on silicon substrates by chemical vapor deposition using the Fe/Al bilayer catalyst approach. The V₂O₅ nanostructures were obtained from the thermal oxidation of metallic vanadium deposited on the VACNTs. Different oxidation temperatures and vanadium thicknesses were used to study the influence of these parameters on the stability of the carbon template and the formation of the V₂O₅ nanostructures. The morphology of the samples was analyzed by scanning electron microscopy, and the structural characterization was performed by Raman, energy-dispersive X-ray, and X-ray photoelectron spectroscopies. Due to the catalytic properties of V₂O₅ in the decomposition of carbonaceous materials, it was possible to obtain supported sponge-like structures based on V₂O₅/CNT composites, in which the CNTs exhibit an increase in their graphitization. The VACNTs can be removed or preserved by modulating the thermal oxidation process and the vanadium thickness. Full article

The investigation into intercalation mechanisms in vanadium pentoxide has garnered significant attention within the realm of research, primarily propelled by its remarkable theoretical capacity for energy storage. This comprehensive review delves into the latest advancements that have enriched our understanding of these intricate mechanisms. Notwithstanding its exceptional storage capacity, the compound grapples with challenges arising from inherent structural instability. Researchers are actively exploring avenues for improving electrodes, with a focus on innovative structures and the meticulous fine-tuning of particle properties. Within the scope of this review, we engage in a detailed discussion on the mechanistic intricacies involved in ion intercalation within the framework of vanadium pentoxide. Additionally, we explore recent breakthroughs in understanding its intercalation properties, aiming to refine the material’s structure and morphology. These refinements are anticipated to pave the way for significantly enhanced performance in various energy storage applications. Full article

Copper metal is a promising anode in aqueous batteries due to its low price, noble reaction potential (0.34 V), high theoretical specific capacity, abundance and chemical stability. However, only a few copper ion storage materials have been reported. Herein, layered vanadium pentoxide is chosen to store copper ions for the first time. Ex situ XRD reveals a unique two phase transition process during cycling. The V₂O₅ electrode shows stable copper ion storage performance. It delivers 91.9 mAh g⁻¹ for the first cycle with a cycle life of as high as 4000 cycles at 1.0 A g⁻¹. This work provides an intriguing copper ion storage material and expands the available options of electrode materials for copper ion storage. Full article

Vanadium is a significant metal, and its derivatives are widely employed in industry. One of the essential vanadium compounds is vanadium pentoxide (V₂O₅), which is mostly recovered from titanomagnetite, uranium–vanadium deposits, phosphate rocks, and spent catalysts. A smart method for the characterization and recovery of vanadium pentoxide (V₂O₅) was investigated and implemented as a small-scale benchtop model. Several nondestructive analytical techniques, such as particle size analysis, X-ray fluorescence (XRF), inductively coupled plasma (ICP), and X-ray diffraction (XRD) were used to determine the physical and chemical properties, such as the particle size and composition, of the samples before and after the recovery process of vanadium pentoxide (V₂O₅). After sample preparation, several acid and alkali leaching techniques were investigated. A noncorrosive, environmentally friendly extraction method based on the use of less harmful acids was applied in batch and column experiments for the extraction of V₂O₅ as vanadium ions from a spent vanadium catalyst. In batching experiments, different acids and bases were examined as leaching solution agents; oxalic acid showed the best percent recovery for vanadium ions compared with the other acids used. The effects of the contact time, acid concentration, solid-to-liquid ratio, stirring rate, and temperature were studied to optimize the leaching conditions. Oxalic acid with a 6% (w/w) to a 1/10 solid-to-liquid ratio at 300 rpm and 50 °C was the optimal condition for extraction (67.43% recovery). On the other hand, the column experiment with a 150 cm long and 5 cm i.d. and 144 h contact time using the same leaching reagent, 6% oxalic acid, showed a 94.42% recovery. The results of the present work indicate the possibility of the recovery of vanadium pentoxide from the spent vanadium catalyst used in the sulfuric acid industry in Jordan. Full article

Interstitial lung diseases (ILDs) are lethal lung diseases characterized by pulmonary inflammation and progressive lung interstitial scarring. We previously developed a mouse model of ILD using vanadium pentoxide (V₂O₅) and identified several gene candidates on chromosome 4 associated with pulmonary fibrosis. While these data indicated a significant genetic contribution to ILD susceptibility, they did not include any potential associations and interactions with the mitochondrial genome that might influence disease risk. To conduct this pilot work, we selected the two divergent strains we previously categorized as V₂O₅-resistant C57BL6J (B6) and -responsive DBA/2J (D2) and compared their mitochondrial genome characteristics, including DNA variants, heteroplasmy, lesions, and copy numbers at 14- and 112-days post-exposure. While we did not find changes in the mitochondrial genome at 14 days post-exposure, at 112 days, we found that the responsive D2 strain exhibited significantly fewer mtDNA copies and more lesions than control animals. Alongside these findings, mtDNA heteroplasmy frequency decreased. These data suggest that mice previously shown to exhibit increased susceptibility to pulmonary fibrosis and inflammation sustain damage to the mitochondrial genome that is evident at 112 days post-V₂O₅ exposure. Full article