CeO2 Nanoparticles Research Articles

Morphophysiological, biochemical, and nutrient response of spinach (Spinacia oleracea L.) by foliar CeO2 nanoparticles under elevated CO2

Nanomaterials offer considerable benefits in improving plant growth and nutritional status owing to their inherent stability, and efficiency in essential nutrient absorption and delivery. Cerium oxide nanoparticles (CeO2 NPs) at optimum concentration could significantly influence plant morpho-physiology and nutritional status. However, it remains unclear how elevated CO2 and CeO2 NPs interactively affect plant growth and quality. Accordingly, the ultimate goal was to reveal whether CeO2 NPs could alter the impact of elevated CO2 on the nutrient composition of spinach. For this purpose, spinach plant morpho-physiological, biochemical traits, and nutritional contents were evaluated. Spinach was exposed to different foliar concentrations of CeO2 NPs (0, 25, 50, 100 mg/L) in open-top chambers (400 and 600 CO2 μmol/mol). Results showed that elevated CO2 enhanced spinach growth by increasing photosynthetic pigments, as evidenced by a higher photosynthetic rate (Pn). However, the maximum growth and photosynthetic pigments were observed at the highest concentration of CeO2 NPs (100 mg/L) under elevated CO2. Elevated CO2 resulted in a decreased stomatal conductance (gs) and transpiration rate (Tr), whereas CeO2 NPs enhanced these parameters. No significant changes were observed in any of the measured biochemical parameters due to increased levels of CO2. However, an increase in antioxidant enzymes, particularly in catalase (CAT; 14.37%) and ascorbate peroxidase (APX; 10.66%) activities, was observed in high CeO2 NPs (100 mg/L) treatment under elevated CO2 levels. Regarding plant nutrient content, elevated CO2 significantly decreases spinach roots and leaves macro and micronutrients as compared to ambient CO2 levels. CeO2 NPs, in a dose-dependent manner, with the highest increase observed in 100 mg/L CeO2 NPs treatment and increased roots and shoots magnesium (211.62–215.49%), iron (256.68–322.77%), zinc (225.89–181.49%), copper (21.99–138.09%), potassium (121.46–138.89%), calcium (118.22–91.32%), manganese (133.15–195.02%) under elevated CO2. Overall, CeO2 NPs improved spinach growth and biomass and reverted the adverse effects of elevated CO2 on its nutritional quality. These findings indicated that CeO2 NPs could be used as an effective approach to increase vegetable growth and nutritional values to ensure food security under future climatic conditions.

Development of Technology for the Synthesis of Nanocrystalline Cerium Oxide Under Production Conditions with the Best Regenerative Activity and Biocompatibility for Further Creation of Wound-Healing Agents

Background/Objectives: The issue of effective wound healing remains highly relevant. The objective of the study is to develop an optimal method for the synthesis of nanosized cerium oxide powder obtained via the thermal decomposition of cerium carbonate precipitated from aqueous nitrate solution for the technical creation of new drugs in production conditions; the select modification of synthesis under different conditions based on the evaluation of the physicochemical characteristics of the obtained material and its biological activity, and an evaluation of the broad-spectrum effect on cells involved in the regeneration of skin structure as well as antimicrobial properties. Methods: Several modes of the industrial synthesis of cerium dioxide nanoparticles (NPs) were carried out. The synthesis stages and the chemical and physical parameters of the obtained NPs were described using transmission electron microscopy (TEM), X-ray diffraction, Raman spectroscopy, and mass spectrometry. The cell cultures of human fibroblasts and keratinocytes were cultured with different concentrations of different nanoceria variations, and the cytotoxicity and the metabolic and proliferative activity were investigated. An MTT test and cell counting were performed. The antimicrobial activity of CeO2 variations at a concentration of 0.1–0.0001 M against Pseudomonas aeruginosa was studied. Results: The purity of the synthesized nanoceria powders in all the batches was >99.99%. According to TEM data, the size of the NPs varied from 1 nm to 70 nm under different conditions and methodologies. The most optimal technology for the synthesis of the nanoceria with the maximum biological effect was selected. A method for obtaining the most bioactive NPs of optimal size (up to 10 nm) was proposed. The repeatability of the results of the proposed method of nanoceria synthesis in terms of particle size was confirmed. It was proven that the more structural defects on the surface of the CeO2 crystal lattice, the higher the efficiency of the NPs due to oxygen vacancies. The strain provided the best redox activity and antioxidant properties of the nanoceria, which was demonstrated by better regenerative potential on various cell lines. The beneficial effect of synthesized nanoceria on the proliferative and metabolic activity of the cell lines involved in skin regeneration (human fibroblasts, human keratinocytes) was demonstrated. The antimicrobial effect of synthesized nanoceria on the culture of the most-resistant-to-modern-antibiotics microorganism Pseudomonas aeruginosa was confirmed. The optimal concentrations of the nanoceria to achieve the maximum biological effect were determined (10−3 M). Conclusions: It was possible to develop a method for the industrial synthesis of nanoceria, which can be used to produce drugs and medical devices containing CeO2 NPs.

Facile fabrication of redox nanoparticles loaded with exosomal-miRNAs and resveratrol as glycation inhibitor in alleviating the progression and development of diabetic cataract.

Diabetic cataract (DC) represents a highly prevalent ocular manifestation resulting from diabetes often culminating in vision impairment among individuals with diabetes. Regrettably, the armamentarium of pharmaceutical interventions capable of both delaying and thwarting the onset of DC remains conspicuously sparse. Based on contemporary investigations, the pathogenesis of DC is prominently influenced by oxidative harm to the crystalline lens and the nonenzymatic glycosylation of lens proteins. Consequently, we have developed self-regenerating cerium oxide nanoparticles (CeO2 NPs), enveloped with resveratrol (RSV) and exosomal-microRNA (miRNA) to alleviate the effects of DC in an in vitro model. Moreover, the inclusion of RSV within CeO2 NPs serves a dual purpose. It can act as an antioxidant, minimizing glycation, and induce oxidative stress by effectively neutralizing reactive oxygen species (ROS). Additionally, it serves as a glycation inhibitor effectively preventing the cross-linking. Consequently, it helps minimize the glucose level in hemoglobin and inhibits the formation of advanced glycation end products (AGEs). Likewise, the CeO2-exosomal-miRNA when treated alone found to slightly impede the viability of human lens epithelial cells (HLEC) and induce apoptosis by suppressing the expression of α-crystalline gene (CRYAA). Particularly, miRNAs target genes associated with oxidative stress pathways, protein glycation, and the generation of AGEs, hence preventing structural damage to lens proteins. Compared with CeO2, RSV-CeO2, and miRNA-RSV-CeO2, the presence of miRNA-RSV-CeO2 led to a significant decrease in hemoglobin glycation. Remarkably, miRNA-RSV-CeO2 NPs attenuate the formation of malondialdehyde (MDA) and conjugated dienes (CD) with a relative value of 14.63 and 11.37nmol/mg. As per the report, this method presents a promising opportunity to implement the proposed material combination for attenuating diabetic cataracts.

Recycling waste tires into sustainable biofuel for replacing petroleum fuel in diesel engines using nanoparticles and biohydrogen.

In this paper, the production of pyrolyzed oil in lab scale plant and its possible use in variable speed diesel engine with nanoparticle and secondary fuel oxy-hydrogen gas is investigated. The pyrolyzed oil is produced from waste tires in lab scale plant, and after its distillation, it is blended with neat diesel in the proportion of 20:80 (TDF). The different testing fuels are prepared by mixing nanoparticle CeO2 (NP) at the concentrations 50ppm and 100ppm with blended fuel (named as TDF-NP50 and TDF-NP100). While in the testing phase, the HHO gas is supplied through specially designed venturi at fixed flow rate (fuel designated as TDF-NP50-HHO and TDF-NP100-HHO). The focus of current investigation is to investigate the combined impact of inducting HHO with nanoparticle mixed pyrolyzed blends on engine performance and emissions characteristics. The pyrolyzed blended fuel deteriorate the BTE, BSFC, emissions of HC and NOx while improves the CO emission. The improvement in all the characteristics can be achieved by introducing CeO2 nanoparticle at 50ppm and 100ppm which improves BTE by 15-24%, BSFC by 2.2-4.2%, HC by 8-18%, CO by 7-12%, and NOx by 7-16%. The further improvement can be achieved by inducting HHO gas, which are BTE 11%, BSFC 5-8%, HC 15%, and CO 13-16%. However, the NOx emission is increased by 14-17%. Hence, the waste tire-derived pyrolyzed oil along with green hydrogen and nanoparticles CeO2 can be used as a sustainable transportation fuel in existing CI engine.

Influence of Foliar Application of Nanoparticles on Low Temperature Resistance of Rice Seedlings

Chilling stress, a common abiotic factor, adversely affects the growth and biomass of rice seedlings during the early stages, ultimately reducing the yield. Effective strategies to mitigate these negative impacts are essential for improving rice productivity. The application of nanotechnology in agriculture, particularly nanoparticles (NPs), has shown a promising effect in alleviating chilling stress in plants. This study evaluates the effects of various nanoparticles, ZnO (0, 50, 100, and 200 mg/L), Fe2O3 (0, 50, 75, and 100 mg/L), TiO2 (0, 50, 75, and 100 mg/L), and CeO2 (0, 50, 75, and 100 mg/L) on the chilling resistance with one control (a water spray) under a normal temperature. Four rice cultivars: LLY-7108 and XZX-6 (Low-temperature-tolerant), and LLY-32 and ZJZ-17 (Low-temperature-susceptible) were tested in this experiment. Rice seedlings were subjected to low temperature conditions (12 h light 14 °C/12 h dark, at 10 °C) for five days, followed by seven days of recovery. The results of this study demonstrate that NPs significantly enhanced seedling height fresh/dry weight and root length compared to untreated controls under chilling stress. NP treatment also reduced the reactive oxygen species (ROS), malondialdehyde (MDA), and proline content, while enhancing superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities, thereby mitigating oxidative damage. The four rice varieties exhibited clear signs of rapid growth recovery and positive physiological changes due to NPs’ application. Among the tested cultivars, LLY-7108 showed the most substantial recovery and physiological responses, while ZJZ-17 exhibited the least. The findings of this study indicate that the foliar application of ZnO (100 mg/L), Fe2O3 (50 mg/L), TiO2 (50 mg/L), and CeO2 (75 mg/L) NPs effectively mitigates chilling stress in rice seedlings, likely by enhancing the antioxidant enzymatic activity while reducing the oxidative damage. This study highlights the potential of NPs as effective agents in reducing the adverse effects of chilling stress on rice.

Stability Assessment Through Dynamic Light Scattering and Rheological Study of Hexanoic Acid-Surface-Modified Cerium Oxide Nanoparticles in Cyclohexane at Low Concentration

The stability of 1wt% cerium oxide (CeO2) nanoparticles in cyclohexane is assessed in this paper. To do so, first, n-hexanoic acid (C6-) surface-modified CeO2 nanoparticles were synthesized by heating the aqueous Ce(OH)4 suspension at 400 °C and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high regulation transmission electron microscopy (HRTEM), Fourier transform infrared (FTIR) spectroscopy and thermogravimetric analysis (TGA). XRD pattern indicated the crystalline structure and TEM showed the cubic shape of the synthesized CeO2 nanoparticles with an average size of 4.5 nm. Next, 1 wt% CeO2–cyclohexane dispersion (nanofluids) was prepared simply by dispersing the required amounts of CeO2 nanoparticles in cyclohexane. Finally, the stability of CeO2–cyclohexane was assessed by dynamic light scattering (DLS) and rheological study. DLS measurement revealed that the 1wt% CeO2–cyclohexane nanofluid has good dispersibility with a small DLS diameter (~6 nm) comparable to that of the pristine particle diameter measured by TEM. Also, the rheology study depicted the Newtonian behavior of prepared nanofluids which indicated its excellent stability. Jagannath University Journal of Science, Volume 11, Number 1, June 2024, pp. 23−30

Chitosan xerogel embedded with green synthesized cerium oxide nanoparticle: An effective controlled release fertilizer for improved cabbage growth

With the growing awareness on the adverse effects of conventional fertilizers; the use of sustainable and controlled release fertilizers has garnered much significance. In the present study, we report the synthesis of chitosan-benzaldehyde Schiff base xerogel incorporated with green synthesized cerium oxide nanoparticle using Psidium guajava leaves extract as a sustainable fertilizer. Spherical CeO2 NPs having an average particle size of 15.3 nm and zeta potential of – 39.9 mV was obtained. The urea-loaded nanocomposite xerogel (CsB@U/CeO2) was examined for cabbage growth. The water retention capacity extended for >2 weeks. A controlled release profile for urea was accomplished from CsB@U/CeO2 for a period extending for 30 days. The kinetics assay suggested that presence of CeO2 NPs asserted a greater role in urea-controlled release from the CsB@U/CeO2 nanocomposite hydrogel owing to polymer relaxation. The growth parameters of cabbages such as head height, diameter, fresh head weight, head circumference was enhanced in plants fertilized by CsB@U/CeO2 as compared to urea. Furthermore, the phenolic content, free radical scavenging activity, protein content, sugar and flavonoid content were also found higher in CsB@U/CeO2 fertilized plants. This study puts forth CsB@U/CeO2 xerogel can be potentially harnessed as an alternative to urea in sustainable agriculture.

Cerium Oxide Nanoparticles (CeO2 NPs) Enhance Salt Tolerance in Spearmint (Mentha spicata L.) by Boosting the Antioxidant System and Increasing Essential Oil Composition

Salinity represents a considerable environmental risk, exerting deleterious effects on horticultural crops. Nanotechnology has recently emerged as a promising avenue for enhancing plant tolerance to abiotic stress. Among nanoparticles, cerium oxide nanoparticles (CeO2 NPs) have been demonstrated to mitigate certain stress effects, including salinity. In the present study, the impact of CeO2 NPs (0, 25, and 100 mg L−1) on various morphological traits, photosynthetic pigments, biochemical parameters, and the essential oil profile of spearmint plants under moderate (50 mM NaCl) and severe (100 mM NaCl) salinity stress conditions was examined. As expected, salinity reduced morphological parameters, including plant height, number of leaves, fresh and dry weight of leaves and shoots, as well as photosynthetic pigments, in comparison to control. Conversely, it led to an increase in the content of proline, total phenols, malondialdehyde (MDA), hydrogen peroxide (H2O2), and antioxidant enzyme activities. In terms of CeO2 NP applications, they improved the salinity tolerance of spearmint plants by increasing chlorophyll and carotenoid content, enhancing antioxidant enzyme activities, and lowering MDA and H2O2 levels. However, CeO2 NPs at 100 mg L−1 had adverse effects on certain physiological parameters, highlighting the need for careful consideration of the applied concentration of CeO2 NPs. Considering the response of essential oil compounds, combination of salinity stress and CeO2 treatments led to an increase in the concentrations of L-menthone, pulegone, and 1,8-cineole, which are the predominant compounds in spearmint essential oil. In summary, foliar application of CeO2 NPs strengthened the resilience of spearmint plants against salinity stress, offering new insights into the potential use of CeO2 NP treatments to enhance crop stress tolerance.

In situ synthesis of nano-CeO2 and chitosan composite

Nanosized cerium oxide (CeO2) particles were prepared by co-precipitation method using chitosan as a template, cerium (III) nitrate and cerium (IV) sulfate as starting materials and aqueous ammonia solution as a precipitating agent. XRD data indicate that cerianite with face-centered cubic phase is formed in the reaction systems. The size of the coherent scattering regions is about 3 nm or less. FTIR spectroscopy data indicate the interaction of polymer molecules with the inorganic component. The shift of absorption bands related to N-H bonds for composites with Ce(III) and Ce(IV) compared to chitosan indicates the interaction of amino groups with CeO2 particles. The application of chitosan as a matrix for the synthesis of CeO2 nanoparticles showed that this approach is more economical and easier to produce nanomaterials for various applications.

Phyto-mediated fabrication of cerium oxide nanoparticles using Mollugo oppositifolia L aqueous leaf extract: Antibacterial, antitonicity, and molecular docking studies

The use of bio-processes for synthesizing metal oxide nanoparticles represents a forefront area of research in nanotechnology. This study introduces a rapid and eco-friendly approach for producing cerium oxide nanoparticles (CeO2 NPs) utilizing the aqueous extract of Mollugo oppositifolia L leaves as a catalyst. The synthesized CeO2 NPs underwent comprehensive characterization through scanning electron microscopy (SEM), X-ray diffraction (XRD), ultraviolet–visible spectroscopy (UV–Vis), and Fourier transform infrared spectroscopy (FT-IR). Furthermore, the antimicrobial activity of the CeO2 NPs was assessed in vitro against various bacterial strains, demonstrating a concentration-dependent inhibition zone when exposed to concentrations ranging from 25 to 100 μg/mL. Antitonicity activity results of the synthesized CeO2 NPs revealed significant activity. Further molecular docking studies also revealed that the synthesized CeO2 NPs have better docking ability compared to control Streptomycin in E. coli topoisomerase II DNA gyrase B (PDB ID:1KZN).

Experimental study on the cerium oxide nanoparticles doped in diesel fuel improving the cold start performance of diesel engines at high-altitude and low-temperature environments

CeO2 nanoparticles are effective fuel additives that enhance fuel spray, atomization, and combustion characteristics due to their high catalytic activity and excellent thermal properties. When added to fuel, CeO2 nanoparticles significantly improve in-cylinder combustion, and engine performance, and reduce pollutant emissions under normal engine operating conditions. Diesel engines encounter persistent challenges during cold starts at low temperatures and high altitudes. However, there is limited research on the effects of CeO2 nanoparticles on ignition and combustion at low temperatures and cold start performance. This study aims to evaluate the impact of CeO2 nanoparticles doping in diesel fuel on the cold start performance of diesel engines in high-altitude and low-temperature environments. Diesel fuel doped with CeO2 nanoparticles at various concentrations was prepared using magnetic stirring and ultrasonication. The cold start performance of the test engine was assessed in an environmental chamber. This work investigated and evaluated the improvements of CeO2 nanoparticles on cold start performance from three perspectives: general low-temperature conditions, high-altitude environments, and extreme low-temperature scenarios with diethyl ether premixing. Experimental results indicate that incorporating CeO2 nanoparticles expanded the critical temperature required for a successful cold start from 0 °C to −5 °C. At high altitudes, the addition of CeO2 nanoparticles effectively increased the proportion of efficient combustion, evidenced by single peak and parent peak patterns during cold starts. CeO2 nanoparticles facilitated the transition from low-temperature to high-temperature reactions, promoting fuel ignition during the first injection cycle and reducing speed fluctuations during cold starts with diethyl ether premixing at −40 °C. Furthermore, adding CeO2 nanoparticles prevented detonation and rapid pressure surges during cold starts. Overall, doping diesel fuel with CeO2 nanoparticles proves to be an effective method for enhancing cold start performance in diesel engines. This study offers a novel approach for improving diesel engine cold start performance in high-altitude and low-temperature conditions.

Enhancing engine performance, combustion, and emissions characteristics through CeO2-modified cottonseed biodiesel with hydrogen enrichment: A comprehensive investigation

This investigation delves into the combined use of nanoparticles added biodiesel blends and hydrogen as secondary fuels in CI engines, intending to minimize the reliance on traditional fossil fuels. Calcined wood ash (CWA) has been used as a heterogeneous catalyst for the preparation of cottonseed biodiesel. XRD, SEM and BET analysis was performed to characterize the catalyst. This study evaluates the impact of adding hydrogen and Cerium oxide (CeO2) nanoparticles to cottonseed biodiesel on a CRDI engine. It showed that H2 at an intake rate of 10 L/min improved the engine's overall performance and reduced hazardous emissions. By incorporating the CeO2 nanoparticles (75 ppm) in a cottonseed biodiesel blend and injecting H2 in the engine the BTE was enhanced by 27.8% and BSFC was decreased by 4.41%. There was a reduction of 24%, 22.8%, 6.42%, and 69.5% for HC, CO, CO2 and smoke emissions. On the other hand, NOx rose by 9.3% compared to diesel. The combustion characteristics, such as cylinder pressure showed 26.5% improvement at full load on inclusion of H2. Additionally, under maximum load, the blend C20 + CeO2+H2 has the shortest ignition delay and combustion duration leading to higher engine efficiency. The results of this investigation offer valuable insights into the potential of biodiesel-hydrogen dual-fuel strategies to reduce the environmental impact of CI engines while promoting sustainable energy practices.

Silver vanadate and cerium oxide decorated graphene oxide ternary heterostructure nanocomposites: structural, electrochemical, and optoelectrical properties

In the present work, we synthesized a novel ternary heterostructure nanocomposite comprising Silver Vanadate and Cerium Oxide Decorated Graphene Oxide (AgVO3-CeO2/GO) using a straightforward and cost-effective method. Six samples, including GO, CeO2, CeO2/GO, AgVO3, AgVO3/GO, and CeO2-AgVO3/GO, were prepared. The structural, morphological, electrochemical, and optoelectrical properties of these samples were thoroughly investigated. X-ray diffraction (XRD) demonstrated the presence of graphene oxide, cerium oxide, and silver vanadate phases, while transmission electron microscopy (TEM) showed the single crystalline nature of AgVO3 and the dispersion of CeO2 and AgVO3 nanoparticles within the GO matrix. The heterojunctions between different components facilitated efficient charge transfer and enhanced optoelectronic performance. External quantum efficiency was measured using a 532 nm laser beam, and the electrical properties were evaluated under dark and illuminated conditions with a two-point probe setup. The inclusion of CeO2 and AgVO3 nanoparticles in the GO matrix improved charge transport and interfacial charge transfer processes. These findings highlight the potential of these materials for various optoelectronic applications, including photodetection, sensing, and energy harvesting, with further optimization potentially leading to high-performance devices with enhanced functionality and efficiency.

UV Light‐Driven Photocatalytic Performance of CeO2 and Co Ion‐Doped CeO2 Nanoparticles: High‐Efficiency Electrochemical and Chromaticity Blue LED Application

AbstractThe study assesses the efficacy of CeO2 nanoparticles synthesised via the hydrothermal method for UV‐induced catalytic activity in decomposing cobalt complexes. Various analyses, including X‐ray diffractometry (XRD), Raman spectroscopy, scanning electron microscopy (SEM), high‐resolution transmission electron microscopy (HR‐TEM), and UV‐Vis spectrophotometry were employed to investigate the impact of cobalt on cerium oxide's morphology, optical, electrochemical, and microstructural characteristics. The XRD analysis revealed a cubic structure in the fluorite‐type pattern, primarily oriented along the (111) direction. Raman spectroscopy supported these findings, identifying an active mode peak at 464 cm−1 and indicating the presence of F2g cubic fluorite. SEM imaging displayed cleavage and uniform, densely packed grains. Elemental analysis confirmed the presence of Ce, O, and Co, corroborated by X‐ray Photoelectron Spectroscopy (XPS) data. Optical measurements indicated a band gap starting at 3.03 eV, which decreased with increasing Co ratio, reaching 2.9 eV at 4 % cobalt incorporation. Furthermore, cyclic voltammetry experiments demonstrated that Co‐doped samples exhibited enhanced ion storage capacity. These comprehensive analyses underscore the potential of Co‐doped CeO2 nanoparticles for UV‐induced catalytic activity, offering valuable insights into their structural and functional properties.

CeO2 loaded on L-tryptophan functionalized graphitic carbon nitride colorimetric-fluorescent dual-channel detection

In this study, a nanocomposite with CeO2 loaded on L-tryptophan functionalized graphitic carbon nitride (CeO2/L-g-C3N4) was developed by a facile two-step method. Firstly, L-tryptophan functionalized graphitic carbon nitride (L-g-C3N4) was achieved via π-π stacking interactions through a physical ultrasonic treatment process, which had better dispersibility in water than Bulk-g-C3N4. Then the final product of CeO2/L-g-C3N4 was obtained by a hydrothermal co-precipitation technique with cerium nitrate as precursor. The characterization of morphology indicated that CeO2 nanoparticles evenly distributed on the surface of CeO2/L-g-C3N4, which might be attributed to L-tryptophan offering more bonding sites (–COOH) for the deposition of nanoparticles. The material exhibited excellent oxidase-mimicking activity, which could catalyze the colorless 3,3′,5,5′-tetramethylbenzidine (TMB) into the blue-colored oxidized TMB product (oxTMB), and a new hydroquinone (HQ) colorimetric sensing strategy was proposed. And theoretical simulations indicate that the increased enzymatic activity is mainly attributable to the reduced binding energy of absorbed intermediates. Additionally, due to the material’s exceptional fluorescence properties, combined with the inner filter effect and redox reactions, a unique on–off-on fluorescence sensing mechanism had been successfully developed for the detection of Cr(VI) and SO32−.

Determination of Structural Elements of Hydrothermally Synthesized CeO₂ Nanoparticles by Monshi, Williamson–Hall, Halder–Wagner, and Size–Strain Plot Methods, and Effect of Annealing Temperature

AbstractCeO₂ nanoparticles are synthesized hydrothermally using CTAB as a surfactant, cerium nitrate hexahydrate (Ce(NO3)3·6H₂O) as a precursor and urea. The synthesized CeO₂ nanoparticles are characterized by Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction peak profile analysis (XRD), Scanning electron microscopy (SEM), and UV–vis. The X‐ray diffraction results revealed that the sample is crystalline with a face centered cubic (fcc) phase having cubic fluorite structure. The structural elements of prepared samples have been investigated by various methods. The Monshi, W–H analysis, size–strain plot, and H–W methods are used to study crystallite sizes and lattice strain on the peak broadening of CeO₂ nanoparticles. Further, the lattice constant of the cubic fluorite has also been estimated from the Nelson–Riley plot. The parameters, including strain, stress, and energy density value, are calculated for all the reflection peaks of X‐ray diffraction corresponding to cubic fluorite phase of CeO₂ lying in the range 20°–80° and at different temperatures.

Enhancing wind turbine blade protection: Solid particle erosion resistant ceramic oxides-reinforced epoxy coatings

Wind energy has been regarded as one of the renewable energy sources to rely on in the future. In this aspect, wind turbine blade maintenance is quite a challenge in tropical areas like India. One of the main reasons why wind turbine blades get damaged and produce less energy is solid particle erosion. In the present work, nanocomposite epoxy (EP) coatings reinforced with Al2O3, ZrO2, and CeO2 nanoparticle fillers have been applied on glass fiber reinforced polymer (GFRP) substrates using a simple spray coating method. These nanoparticles have been prepared in-house by solution combustion synthesis (SCS) route using urea, glycine, and oxalyl dihydrazide fuels. X-ray diffraction, field emission scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy have been used to characterize the materials and coatings. EP coatings with different Al2O3, ZrO2, and CeO2 nanoparticle concentrations have been subjected to solid particle erosion resistance tests at impinging angles of 30°, 60° and 90°. ZrO2 and CeO2 nanoparticle-reinforced EP coatings show better resistance to solid particle erosion than Al2O3-reinforced coatings. Estimated average erosion rates are 17 and 11.3 × 10−3 mm3 g−1, respectively, for epoxy coatings with 20 and 40 wt% ZrO2 nanoparticles. However, GFRP substrate and neat EP coating show much higher erosion rates with respect to nanoparticles-reinforced EP coatings. To ascertain a correlation between H3/E2 and the solid particle erosion rates of the coatings, nanoindentation tests have been carried out. Tensile strength and initial modulus of all the coatings are found to be directly proportional to the average erosion rates, whereas, elongation at break shows an inverse relationship with the average erosion rate. This correlation of mechanical properties with solid particle erosion performance can play a critical role in the development of realistic simulation of protective coatings for wind turbine blades.

Exploration of Physical, Optical, and Electrical Properties of Mg-Doped CeO2 Nanoparticles for Photovoltaic Device Applications

Exploration of Physical, Optical, and Electrical Properties of Mg-Doped CeO2 Nanoparticles for Photovoltaic Device Applications

Electrochemical exfoliation of graphene nanosheets and development of a novel efficient Ni-CeO2-Gr ternary nanocomposite coatings for dual functional anti-corrosion and wear-resistance

Nickel-based coatings offer excellent corrosion, wear resistance, and mechanical strength, and can be further improved with additives, making them ideal for harsh environments like marine and chemical industries. In the present study, graphene (Gr) nanosheets were synthesized via electrochemical exfoliation and a novel Ni-CeO2-Gr nanocomposite coating was prepared by an electrochemical co-electrodeposition technique on a Cu substrate in a traditional Watts bath. The coatings (pure Ni, Ni-Gr, Ni-CeO2 and the ternary Ni-CeO2-Gr) were characterized using optical microscopy, scanning electron microscopy (SEM) coupled with energy-dispersive spectrometry (EDS), X-ray diffraction (XRD), Raman spectroscopy, Vickers microhardness and micro-scratch tests. The electrochemical properties of the coatings were evaluated by electrochemical impedance (EIS) and DC-polarization measurements in 0.5 M NaCl. SEM-EDS, Raman, and XRD analysis confirmed the successful synthesis of high-quality graphene and the incorporation of CeO2 nanoparticles and graphene nanosheets into the nickel coating matrix. It was found that the ternary Ni-CeO2-Gr coating exhibited a high microhardness (915.6 HV), improved cohesive strength and enhanced corrosion resistance (544 KΩ.cm−2) compared to pure Ni coatings (30 KΩ.cm−2) due to the synergistic effect of the graphene and CeO2 duplex layer within the Ni matrix, forming a robust anticorrosion barrier. These findings offer valuable insights into the designing highly efficient materials for corrosion protection.

Investigate growth of Paris polyphylla under synergic effects of CeO2 and SiO2 using as fertilizers

This study successfully synthesized SiO2 and CeO2 nano-materials to fertilize for Paris polyphylla (P. polyphylla). The obtained results indicated that nano CeO2 and SiO2 enhanced root growth and plan height of the P. polyphylla, respectively. This was due to the P. polyphylla absorbed SiO2 nano particles via roots and transferred them to the epidermis walls and vascular bundle of stem and leaves to protect as well as to induce growth of aboveground parts while the P. polyphylla also absorbed CeO2 nanoparticles and retained them in the epidermal roots to provide a medium culture accelerating the nutrient uptake of roots to significantly improve its growth. The simultaneously use of nano CeO2 and SiO2 greatly induced both root growth and plan height of the P. polyphylla. The extraction experiments suggested that significant amounts of gracillin, an important medicinal compound, accumulated in the P. polyphylla rhizome. Gracillin content in the rhizome of the CeO2 fertilized P. polyphylla was also greatly higher than that in the SiO2 fertilized P. polyphylla. Thus, the nano CeO2 not only promoted the development but also enhanced formation of gracillin in the rhizome of the P. polyphylla.