Cerium Oxide Nanoparticles Research Articles

Investigating the improvements in morphometric and mechanical properties of mild steel coated with polymer-based hybrid nano composites

The main objective of this paper is to investigate the coexistence of polymers and nanoparticles, demonstrating improved mechanical and corrosion resistance characteristics when applied to mild steel surfaces. For this investigation, various polymer-based hybrid nanocomposite combinations were considered. Combinations of nanomaterials, such as multiwalled carbon nanotubes (MWCNTS), zinc oxide (ZnO), cerium oxide (CeO2), silicon oxide (SiO2), and graphene oxide nanoparticles (GO), as well as polymers including polyester, phenolic, epoxy, and polyurethane were employed. Mild steel samples covered with hybrid nano composites underwent 3.5% NaCl immersion and standard Salt Spray (Fog) test method ASTM B117:2016 to evaluate their corrosion resistant qualities. Tensile strength test (A370:2017) and hardness test [IS 101(Part-5, Sec.2):1988] were performed and determined the mechanical properties. An ideal proportion of polymer and nanoparticles combination that results in both enhanced mechanical and corrosion resistance characteristics was determined in this study. From the obtained results, epoxy resin has been exhibited a 97% corrosion resistance, with a 10% increase in tensile strength around 700 mg of surface hardness. The MSPS3 recorded with the highest of all the combination values of 89% corrosion resistance, 400 mg of surface scratch hardness and 25% increased tensile strength. In case of MZPU2, 80% corrosion resistance, 25% increased tensile strength with 600 mg of surface hardness. Whereas MGPH1 shown 69% anticorrosion, 600 mg of scratch hardness and 27% rise in tensile strength. With these outputs, this research can be applied to various materials for different engineering applications.

Iron incorporated porous cerium oxide nanoparticles as an efficient photocatalyst for different hazardous elimination

Porous ceria (CeO2) nanoparticles and iron-doped porous ceria with different iron contents (1 wt%, 2.5 wt%, 5 wt% and 10 wt%) were prepared using a one-pot simple process. Several characterization techniques were applied to characterize the prepared materials, including inductively coupled plasma (ICP) elemental analysis, X-ray diffraction (XRD), Fourier transform infrared (FTIR), N2 sorption measurements, scanning electron microscopy (SEM), high resolution-transmission electron microscopy (HR-TEM), and DR-UV-Vis. The obtained results confirm the incorporation of iron ions in the CeO2 lattice, with no evidence for the formation of iron oxide as a separate phase. More importantly, the light absorption property of Fe-doped porous ceria samples is found to be red-shifted and the calculated bandgap decreases from 3.08 to 2.66 eV for pure porous ceria and 10 wt% Fe-doped ceria, respectively. Under the illumination of visible light, the photocatalytic activity of Fe-doped porous ceria was investigated through the decolourization reaction of methyl green aqueous solution as a model contaminant in industrial wastewater. The obtained photocatalytic data show a remarkable increase in activity by almost 4.8 times higher compared to a pure ceria sample. Furthermore, the prepared Fe-doped ceria sample exhibits good reusability up to the fourth consecutive reaction without treatment. Moreover, the best-performing sample was further investigated in two additional photocatalytic reactions; the first is the elimination of phenol in an aqueous solution, while the second is the degradation of a gas mixture containing four short-chain hydrocarbon gases. The results of both reactions confirm the great improvement in the photocatalytic performance of Fe-doped porous ceria compared to a pure porous ceria sample.

Cerium oxide nanoparticles impact on sepsis-induced cerebral injury: Deciphering miRNA / NF-κB/TLR signalling pathway.

Sepsis is regarded as an inflammatory syndrome that consists of complex biochemical and pathophysiological dysregulation, brought on by endogenous factors in response to systemic infection. Sepsis can cause short- and long-term cerebral injury. Cerium oxide nanoparticles (CeO2 NPs) have been reported to possess both anti-inflammatory and antioxidative properties. The current study investigated the potential role of cerium oxide nanoparticles in the management of sepsis-induced brain injury. To achieve this target, forty male albino rats were divided into 4 groups, ten rats each. Group (i) set as a shame group. Group (ii) set as shame group administrated CeO2 NPs. Group (iii) septic group treated with saline and Group (iv) septic group treated with CeO2 NPs. The sepsis model in rats was induced by cecal ligation and puncture (CLP). Results showed CeO2 NPs administration resulted in significant improvement in the survival rate of rats, suppression in serum sepsis biomarkers (CRP, ESM-1, PCT and D- dimer), amelioration of brain inflammatory mediators (TNF-α- IL-6, NF-kB and LTB4) as well as apoptotic markers (Cas-3 and BAX). Furthermore, immunomodulation of miRNAs expression (155,124 and 146a). These findings demonstrate a promising pivotal role of CeO2 NPs treatment in alleviating the deleterious effects induced by sepsis in the brain.

Cerium oxide nanoparticles: Chemical properties, biological effects and potential therapeutic opportunities (Review).

The chemistry of pure cerium oxide (CeO2-x) nanoparticles has been widely studied since the 1970s, especially for chemical catalysis. CeO2-x nanoparticles have been included in an important class of industrial metal oxide nanoparticles and have been attributed a range of wide applications, such as ultraviolet absorbers, gas sensors, polishing agents, cosmetics, consumer products, high-tech devices and fuel cell conductors. Despite these early applications in the field of chemistry, the biological effects of CeO2-x nanoparticles were only explored in the 2000s. Since then, CeO2-x nanoparticles have gained a spot in research related to various diseases, especially the ones in which oxidative stress plays a part. Due to an innate oxidation state variation on their surface, CeO2-x nanoparticles have exhibited redox activities in diseases, such as cancer, acting either as an oxidizing agent, or as an antioxidant. In biological models, CeO2-x nanoparticles have been shown to modulate cancer cell viability and, more recently, cell death pathways. However, a deeper understanding on how the chemical structure of CeO2-x nanoparticles (including nanoparticle size, shape, suspension, agglomeration in the medium used, pH of the medium, type of synthesis and crystallite size) influences the cellular effects observed remains to be elucidated. In the present review, the chemistry of CeO2-x nanoparticles and their impact on biological models and modulation of cell signalling, particularly focusing on oxidative and cell death pathways, were investigated. The deeper understanding of the chemical activity of CeO2-x nanoparticles may provide the rationale for further biomedical applications towards disease treatment and drug delivery purposes.

Colloid Systems and Interfaces Stability of Cerium Oxide Nanoparticles in Aqueous Environments: Effects of pH, Ionic Composition, and Suwanee River Humic and Fulvic Acids

Colloid Systems and Interfaces Stability of Cerium Oxide Nanoparticles in Aqueous Environments: Effects of pH, Ionic Composition, and Suwanee River Humic and Fulvic Acids

Peepal (Ficus Religiosa) leaf extract mediated green synthesis of Lanthanum and Cerium oxide nanoparticles: Characterization and potential biological applications

Peepal (Ficus Religiosa) leaf extract mediated green synthesis of Lanthanum and Cerium oxide nanoparticles: Characterization and potential biological applications

Retracted: Structural, Optical, Antibacterial, and Anticancer Properties of Cerium Oxide Nanoparticles Prepared by Green Synthesis Using Morinda citrifolia Leaves Extract.

[This retracts the article DOI: 10.1155/2022/6835625.].

Phyto-drug (Silymarin)-Encapsulated Cerium Oxide Nanoparticles (S-CeONPs) for İn-Vitro Release, Ameliorating Antimicrobial, Anticancer, Anti-inflammatory and Antioxidant Potential

Phyto-drug (Silymarin)-Encapsulated Cerium Oxide Nanoparticles (S-CeONPs) for İn-Vitro Release, Ameliorating Antimicrobial, Anticancer, Anti-inflammatory and Antioxidant Potential

Multifunctional PVDF/CeO2@PDA nanofiber textiles with piezoelectric and piezo-phototronic properties for self-powered piezoelectric sensor and photodetector

In recent years, multifunctional sensors have attracted significant attention due to their ability to detect different types of signals. However, it still remains a challenge to develop flexible materials with multiple sensing functions. Herein, we propose a strategy to fabricate multifunctional flexible textiles (PCP) that can apply piezoelectric and piezo-phototronic effects to self-powered piezoelectric sensor and photodetector (PD) by utilizing the synergistic effect of polydopamine-coated cerium oxide (CeO2@PDA) nanoparticles and poly (vinylidene fluoride) (PVDF). The CeO2@PDA nanoparticles served as local nucleating agents and photosensitizers for the PVDF, enhancing the polar crystalline phase and inducing piezoelectric effect, semiconductor, and optical process coupling in PCP textiles. The piezoelectric sensors consisting of PCP textiles produced extremely high sensitivity (1–10 kPa: 1.27 V/kPa; 10–50 kPa: 0.085 V/kPa; 50–100 kPa: 0.02 V/kPa) and significant electrical output (25.5 V and 0.37 μA). Besides, the piezoelectric sensor had extensive applications including pulse wave measurement, limb motion detection, and active voice recognition. It's especially noteworthy that the PD based on PCP textiles is sensitive for the detecting of sunlight illumination as confirmed by response time (tOn = 2 s and tOff = 4.6 s). Meanwhile, the fabricated self-powered PD showed significant improvement in output current, confirming the realization of the piezo-phototronic effect in PCP textiles. In this work, the low-cost and high-efficiency multifunctional sensing materials were successfully prepared, providing a novel approach for the next generation of self-powered piezoelectric sensors and photodetectors.

High heat-reflective and superhydrophobicity properties functional fabrics

Infrared reflective materials are pivotal in reducing bicarbon emission and have emerged as a global research focus. This study presents the preparation of kilogram-scale weakly Tb-doped cerium oxide nanocomposites, utilizing a green synthesis approach combining ball milling and high-temperature calcination. Integrating first-principles calculations with experiments analysis, we demonstrate that Tb doping enhances the band gap of cerium oxide, significantly improving its reflective properties. The resulting terbium-doped cerium oxide nanoparticles have good absorption in the visible range while maintaining excellent IR reflectance in the IR band. The near-infrared solar reflectance reaches 85.54 %. Additionally, we developed CeO2:Tb–SiO2 polyester fabrics using an impregnation method. These fabrics show superior IR infrared barrier efficiency (76.58 %) and a notable reduction in inner-surface temperature compared to standard polyester fabrics. The barrier efficiency is enhanced by 27.59 %, and the temperature difference reaches up to 6.1 °C, underscoring their exceptional thermal insulating properties. Moreover, the fabric exhibits remarkable superhydrophobicity, with a contact angle of 152.1°. This novel heat-reflective, self-cleaning, stable rare-earth nano-insulating coating along with its application in polyester fabrics, paves the way for effective temperature regulation. Its potential applications in fabric stain and sun protection are promising, contributing to energy saving and sustainable development.

Protective Properties of Ablated Cerium Oxide Nanoparticles for Cell Cultures under Conditions of Oxidative Stress under Ultraviolet and Ionizing Irradiation

Purpose. Study of the protective properties of ablated cerium oxide nanoparticles for cell cultures in an oxidative reaction under ultraviolet and ionizing irradiation.Methods. Cerium dioxide nanoparticles with high antioxidant activity were obtained using laser ablation. Atomic force microscopy was used to characterize ablated cerium dioxide nanoparticles and cells incubated with cerium dioxide nanoparticles. The protective properties of cerium dioxide nanoparticles were studied after 0 (without incubation), 6and 24-hour incubation using the colorimetric MTT test method.Results. Using laser ablation, cerium oxide nanoparticles with a maximum size of up to 50 nm were obtained. The resulting nanoparticles were incubated with BJ TERT cell lines for 6 and 24 hours. The samples were subjected to ultraviolet (UV) and ionizing irradiation in order to reveal the protective properties of CeO2 nanoparticles. Based on the results of the MTT test, it was found that incubation with cerium dioxide nanoparticles has a pronounced protective effect on the BJ TERT cell line. After UV irradiation, 6-hour and 24-hour incubation of cerium oxide nanoparticles with cell culture provides 15±5% and 20±5% more cell survival, respectively, than without particles. After ionizing radiation, the percentage of survival of cells incubated for 24 hours with cerium nanoparticles also increases by 20±5%.Conclusion. This work shows that ablated cerium dioxide nanoparticles have a protective effect on healthy BJ TERT cells. The work shows that cerium oxide nanoparticles are promising antioxidants that can provide a protective effect for cell cultures from ultraviolet and ionizing radiation.

Cerium Oxide Catalyzed Disproportionation of Hydrogen Peroxide: A Closer Look at the Reaction Intermediate.

Cerium oxide nanoparticles (CNPs) have recently gained increasing interest as redox enzyme-mimetics to scavenge the intracellular excess of reactive oxygen species, including hydrogen peroxide (H2 O2 ). Despite the extensive exploration, there remains a notable discrepancy regarding the interpretation of observed redshift of UV-Visible spectroscopy due to H2 O2 addition and the catalase-mimicking mechanism of CNPs. To address this question, we investigated the reaction mechanism by taking a closer look at the reaction intermediate during the catalase mimicking reaction. In this study, we present evidence demonstrating that in aqueous solutions, H2 O2 adsorption at CNP surface triggers the formation of stable intermediates known as cerium-peroxo (Ce-O2 2- ) and/or cerium-hydroperoxo (Ce-OOH- ) complexes as resolved by Raman scattering and UV-Visible spectroscopy. Polymer coating presents steric hinderance for H2 O2 accessibility to the solid-liquid interface limiting further intermediate formation. We demonstrate in depth that the catalytic reactivity of CNPs in the H2 O2 disproportionation reaction increases with the Ce(III)-fraction and decreases in the presence of polymer coatings. The developed approach using UV-Visible spectroscopy for the characterization of the surface peroxide species can potentially serve as a foundation for determining the catalytic reactivity of CNPs in the disproportionation of H2 O2 .

An experimental investigation of the effects of blending camphor oil infused with jack fruit biodiesel and nanoparticles on the performance, combustion, and exhaust emissions of a compression ignition engine

Growing urbanisation, higher standards of living, and population growth are all factors that will drive up global energy demand. The direct injection of jack fruit biodiesel in compression ignition engine to result in indigent performance and to overcome the addition of nanoparticles of zinc oxide, cerium oxide, and aluminium oxide to biodiesel-camphor blends is the focus of this research. The fuels’ soluble were tested at a temperature range of 30 °C, 50 °C, and 100 °C. One was picked to simulate a diesel engine's performance, combustion, and emissions. Equal parts of zinc oxide, cerium oxide, and aluminium oxide (100 ppm each) were included into the mixture. The inclusion of nanoparticles in the fuel increases its calorific value. Nanoparticles as catalysts enhanced brake-specific fuel consumption by 3.6%, 13.5%, and 17.5% for zinc oxide (ZnO), cerium oxide, (CeO2) and aluminium oxide (Al2O3) compared to diesel at full load. ZnO, CeO2, and Al2O3 nanofuels improved brake thermal efficiency by 15.3%, 10.8%, and 4% at higher loads than BD10C10 at full load. Max heat release increased 10.64%, 9.36%, and 8.8% for ZnO, CeO2, and Al2O3 nanofuels. Carbon monoxide, hydrocarbons, nitrogen oxides, and smoke emissions were reduced when nano-fluid was added in diesel. Directions for using Nano-assisted renewable fuel sources to reduce fossil fuel use as a novel approach in the present study.

Structural, optical and magnetic properties of Cu doped CeO2 nano powders synthesized by solid state reaction

In this research work, the structural, optical, and magnetic properties of Ce1−xCuxO nanoparticles have been reported. Solid state reaction technique was employed to synthesize the nanoparticle samples. The synthesized materials were analysed structural properties from x-ray diffraction (XRD) observed that the crystallite size increased from16.9 nm to 40.43 nm and the lattice constant increased with increase of Cu doping concentration, and the structural properties after doping confirm the absence of other phase and synthesized samples had a cubic structure. Using SEM and EDAX, the nanoparticles surface morphology and elemental composition in investigated. The nanoparticles have a spherical shape and approximately the expected stoichiometric ratio. The optical band gap of copper doped cerium oxide nanoparticles is calculated and found the band gap decreased with increased dopant concentration. Ce1−xCuxO nanoparticles using photoluminescence (PL) analysis at excitation wavelengths of 350 nm revealed emissions of the violet, blue, green, and red regions within the range of 350–700 nm. Vibrating sample magnetometer was found that the samples were room temperature ferromagnetic in nature and strength of magnetic moment increased with increase of doping concentration.

Processing antimicrobial CeO2-TiO2 nanocomposite using supercritical carbon dioxide

A nanocomposite powder of cerium and titanium oxide nanoparticles (NPs) was prepared using supercritical CO2. The characterization of the obtained powder showed spheres or quasi-spheres between 68 and 145 nm, depending on the conditions used. In all tests, N2 physisorption analysis showed that the specific surface area of the samples increased between 30 and 100 times more than of the precursors used. With the ultimate goal of using composite oxide powders for the treatment of oral diseases or tissue regeneration, antimicrobial analysis against S. aureus bacteria, present in oral and skin diseases, showed that the (in-liquid) inhibition of the oxide nanocomposites obtained were higher than that of the raw oxides and very close to the inhibition of an antibiotic such as amoxicillin.

Influence of Nano-CeO2 and Graphene Nanoplatelets on the Conductivity and Dielectric Properties of Poly(vinylidene fluoride) Nanocomposite Films.

Novel three-phase polymer nanocomposites (PNCs) based on cerium oxide (CeO2) nanoparticles (NPs) and graphene nanoplatelets (GNPs) incorporated in a poly(vinylidene fluoride) (PVDF) matrix were formulated using a solution-casting approach. To understand the structural and morphological features of PVDF/CeO2/GNP nanocomposites (NCs), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) analyses were accomplished. The PVDF/CeO2/GNP NCs displayed improved thermal stability which resulted from strong bonding between GNPs and CeO2 NPs and restriction of the polymer chain movement. The introduction of CeO2 NPs and GNPs within the PVDF matrix and good synergy between CeO2 NPs and GNPs led to variable mechanical properties of the prepared NCs. The PVDF/CeO2/GNP NCs portrayed reduced thermal stability, which could be due to the increased mobility of PVDF chains imposed by GNPs leading to the formation of volatile degradation products. Moreover, PVDF/CeO2/GNP NCs exhibited good electrical conductivity and high dielectric permittivity. The obtained dielectric permittivity value for the PVDF/CeO2/GNP NCs was 3-fold greater than PVDF/CeO2 NCs, making these novel tertiary composite materials a probable candidate for energy-storage applications.

Ordered hierarchical superlattice amplifies coated-CeO2 nanoparticles luminescence

Achieving a controlled preparation of nanoparticle superstructures with spatially periodic arrangement, also called superlattices, is one of the most intriguing and open questions in soft matter science. The interest in such regular superlattices originates from the potentialities in tailoring the physicochemical properties of the individual constituent nanoparticles, eventually leading to emerging behaviors and/or functionalities that are not exhibited by the initial building blocks. Despite progress, it is currently difficult to obtain such ordered structures; the influence of parameters, such as size, softness, interaction potentials, and entropy, are neither fully understood yet and not sufficiently studied for 3D systems. In this work, we describe the synthesis and characterization of spatially ordered hierarchical structures of coated cerium oxide nanoparticles in water suspension prepared by a bottom-up approach. Covering the CeO2 surface with amphiphilic molecules having chains of appropriate length makes it possible to form ordered structures in which the particles occupy well-defined positions. In the present case superlattice arrangement is accompanied by an improvement in photoluminescence (PL) efficiency, as an increase in PL intensity of the superlattice structure of up to 400 % compared with that of randomly dispersed nanoparticles was observed. To the best of our knowledge, this is one of the first works in the literature in which the coexistence of 3D structures in solution, such as face-centered cubic (FCC) and Frank-Kasper (FK) phases, of semiconductor nanoparticles have been related to their optical properties.

CeO2NP priming enhances the seed vigor of alfalfa (Medicago sativa) under salt stress.

Soil salinization is a common environmental problem that seriously threatens crop yield and food security, especially through its impact on seed germination. Nanoparticle priming, an emerging seed treatment method, is receiving increasing attention in improving crop yield and stress resistance. This study used alfalfa seeds as materials to explore the potential benefits of cerium oxide nanoparticle (CeO2NP) priming to promote seed germination and improve salt tolerance. CeO2NPs at concentrations up to 500 mg/L were able to significantly alleviate salt stress in alfalfa seeds (200 mM), with 50 mg/L of CeO2NP having the best effect, significantly (P< 0.05) increasing germination potential (from 4.0% to 51.3%), germination rate (from 10.0% to 62.7%), root length (from 8.3cm to 23.1cm), and seedling length (from 9.8cm to 13.7cm). Priming treatment significantly (P< 0.05) increased seed water absorption by removing seed hardness and also reducing abscisic acid and jasmonic acid contents to relieve seed dormancy. CeO2NP priming increased α-amylase activity and osmoregulatory substance level, decreased reactive oxygen species and malonaldehyde contents and relative conductivity, and increased catalase enzyme activity. Seed priming regulated carotenoid, zeatin, and plant hormone signal transduction pathways, among other metabolic pathways, while CeO2NP priming additionally promoted the enrichment of α-linolenic acid and diterpenoid hormone metabolic pathways under salt stress. In addition, CeO2NPs enhanced α-amylase activity (by 6.55%) in vitro. The optimal tested concentration (50 mg/L) of CeO2NPs was able to improve the seed vigor, enhance the activity of α-amylase, regulate the osmotic level and endogenous hormone levels, and improve the salt tolerance of alfalfa seeds. This study demonstrates the efficacy of a simple seed treatment strategy that can improve crop stress resistance, which is of great importance for reducing agricultural costs and promoting sustainable agricultural development.

Tailoring the Structural and Optical Properties of Cerium Oxide Nanoparticles Prepared by an Ecofriendly Green Route Using Plant Extracts.

The present study explores an environmentally friendly green approach to obtain cerium oxide nanoparticles via a biomediated route using Mellisa officinalis and Hypericum perforatum plant extracts as reducing agents. The as-prepared nanoparticles were studied for their structural and morphological characteristics using XRD diffractometry, scanning electron microscopy, Raman, fluorescence and electronic absorption spectra, and X-ray photoelectron spectroscopy (XPS). The XRD pattern has shown the centered fluorite crystal structure of cerium oxide nanoparticles with average crystallite size below 10 nm. These observations were in agreement with the STEM data. The cubic fluorite structure of the cerium oxide nanoparticles was confirmed by the vibrational mode around 462 cm-1 due to the Ce-08 unit. The optical band gap was estimated from UV-Vis reflectance spectra, which was found to decrease from 3.24 eV to 2.98 eV. A higher specific area was determined for the sample using M. officinalis aqueous extract. The EDX data indicated that only cerium and oxygen are present in the green synthesized nanoparticles.

Facet-dependent haloperoxidase-like activities of CeO2 nanoparticles contribute to their excellent biofilm formation suppression abilities

Biofilms adhering to different surfaces have significant negative impacts in various fields. Cerium oxide nanoparticles can serve as mimics of haloperoxidase for biological biofilm inhibition applications. The regulation of the exposed facet of CeO2 nanoparticles influences their efficiency in various catalytic processes. However, there is still a lack of systematic studies on the facet-dependent haloperoxidase-like activity of CeO2. In the present study, the facet-dependent haloperoxidase activities and antibiofilm performance of CeO2 nanoparticles were elucidated through experiment analysis and density function theory calculation. The as-prepared CeO2 nanoparticles inhibited bacterial survival and catalyzed the oxidative bromination of quorum sensing signaling molecules, achieving biofilm inhibition performance. The antibacterial and biofilm formation suppression abilities were consistent with their haloperoxidase activities. The {111}- and {110}-facet CeO2 nanopolyhedra, as well as the {110}- and {100}-facet CeO2 nanorods, which had higher haloperoxidase activity showed better antibiofilm performance than the {100}-facet CeO2 cubes. The present findings provide a comprehensive understanding of the facet-dependent haloperoxidase-like activity of CeO2. Furthermore, engineering CeO2 morphologies with different crystal facets may represent a novel method for significantly adjusting their haloperoxidase-like activity.