α-Fe2O3 Nanoparticles Research Articles

Heterojunction-Based Photocatalytic Degradation of Rose Bengal Dye via Gold-Decorated α-Fe2O3-CeO2 Nanocomposites under Visible-Light Irradiation

Developing photocatalytic nanomaterials with unique physical and chemical features using low-cost and eco-friendly synthetic methods is highly desirable in wastewater treatment. In this work, the magnetically separable α-Fe2O3-CeO2 nanocomposite (NC), with its respective metal oxides of α-Fe2O3 and CeO2 nanoparticles, was synthesized using a combination of hexadecyltrimethylammonium bromide (CATB) and ascorbic acid via the hydrothermal method. To tune the band gap, the heterojunction nanocomposite of α-Fe2O3-CeO2 was decorated with plasmonic Au nanoparticles (Au NPs). The various characterization methods, such as FTIR, UV-vis DRS, XRD, XPS, TEM, EDX, SEM, and PL, were used to determine the properties of the materials, including their morphology, elemental composition, optical properties, band gap energy, and crystalline phase. The nanocomposite of α-Fe2O3-CeO2@Au was utilized to remove Rose Bengal (RB) dye from wastewater using a photocatalytic technique when exposed to visible light. A comprehensive investigation of the impact of the catalyst concentration and initial dye concentration was conducted to establish the optimal photodegradation conditions. The maximum photocatalytic efficiency of α-Fe2O3-CeO2@Au (50 mg L−1) for RB (20 ppm) dye removal was found to be 88.9% in 120 min under visible-light irradiation at a neutral pH of 7 and 30 °C. Various scavengers, such as benzoquinone (BQ; 0.5 mM), tert-butyl alcohol (TBA; 0.5 mM), and ethylenediaminetetraacetic acid (EDTA; 0.5 mM), were used to investigate the effects of different free radicals on the photocatalytic process. Furthermore, the reusability of the α-Fe2O3-CeO2@Au photocatalyst has also been explored. Furthermore, the investigation of the potential mechanism demonstrated that the heterojunction formed between α-Fe2O3 and CeO2, in combination with the presence of deposited Au NPs, led to an enhanced photocatalytic efficiency by effectively separating the photogenerated electron (e−)–hole (h+) pairs.

Synthesis and characterization of α-Fe2O3 nanoparticles for high-performance CO gas sensor

Synthesis and characterization of α-Fe2O3 nanoparticles for high-performance CO gas sensor

Adsorption and photocatalytic degradation activities of a hybrid magnetic mesoporous composite of α-Fe2O3 nanoparticles embedded with sheets-like MgO

Crystal violet (CV), identified as a potential carcinogen, is a synthetic dye prevalent in wastewater from textile and paint industries. Therefore, the current study demonstrates that the hybrid composite of mesoporous magnetic α-Fe2O3 nanoparticles @ sheet-like MgO (Fe2O3@MgO) can be employed as a potential effective sorbent and photocatalyst for CV-removal from polluted water. A comparative study was systematically performed on the CV-removal using MgO and Fe2O3@MgO composite. The physicochemical, textural, and structural properties, morphological features, and elemental composition of mesoporous Fe2O3@MgO composite were intensively investigated. Batch trials were performed to optimize the sorption conditions. The highest CV-uptake efficiency was detected at pH 9 within the adsorption equilibrium time of about 30 min, where the maximum capacity of Fe2O3@MgO was 50.8 mg/g. Under UV irradiation, the Fe2O3@MgO photocatalyst exhibited a high efficiency and fast response toward CV-removal. The mechanism of CV removal was researched through zeta potential (ZP), bandgap, and density functional theory (DFT) calculations. The outcome demonstrated that mesoporous Fe2O3@MgO sorbent/photocatalyst could be recycled and reused ten times, making it a cost-effective solution for removing CV-dye from wastewater. This manuscript suggested that mesoporous Fe2O3@MgO composite is an efficient adsorbent/photocatalyst for fast, affordable, and efficient decontamination of CV-dye from wastewater.

Elucidating the structural and spectroscopic attributes of titania-iron oxide (TiO2-([formula omitted]-Fe2O3)) nanocomposites: Showcasing a pulsed laser ablation in liquid approach

Various nanomaterials with tailored photo-electrochemical and physicochemical attributes became viable for the photo-catalysis and sensors applications. Thus, some new types of TiO2-(α-Fe2O3) nanocomposites were made via the pulse laser ablation in liquid method. These nanocomposites at each value of laser fluence were obtained by mixing the colloidal TiO2 nanoparticles and colloidal (α-Fe2O3) nanoparticles at equal ratio. The stability, structures, morphologies, and optical characteristics of the produced nanocomposites (suspended in deionized water) were customized by changing the laser fluence from 3.5–17.7 J cm−2. The high-resolution transmission electron microscopy micrographs showed the existence of homogeneous dispersion of spherical nanocrystallites (mean diameter 12.4 ± 6.0 nm) in the colloidal suspension. Both X-ray diffraction and Fourier transform infrared profiles of the specimen verified their purity and good nanocrystallinity. Two optical absorption peaks were probed in the range of 240 to 380 nm convoyed by a blue-shift. The spectral edge related to UV–Vis absorption was used to estimate the optical band gap of these nanocomposites. TiO2-(α-Fe2O3) nanocomposites made at optimum laser fluence (10.6 J cm−2) exhibited strong fluorescence with the life time decay of 3.64 μs, indicating the electronic density of states modification due to quantum size effects. The presence of Fe, Ti, and O in the X-ray photoelectron spectroscopy spectra reaffirmed the samples purity. The measured strong negative zeta potential (-33.1 mV) of the optimum TiO2-(α-Fe2O3) nanocomposites confirmed their excellent stability in the colloidal suspension. In short, these nanocomposites may be advantageous as good photo-catalysts for waste water treatment and photo-electrochemical uses.

Quasicrystal Nanosheet/α-Fe2O3 Heterostructure-Based Low Power NO2 Sensors: Experimental and DFT Studies.

Industrial emissions, environmental monitoring, and medical fields have put forward huge demands for high-performance and low power consumption sensors. Two-dimensional quasicrystal (2D QC) nanosheets of metallic multicomponent Al70Co10Fe5Ni10Cu5 have emerged as a promising material for gas sensors due to their excellent catalytic and electronic properties. Herein, we demonstrate highly sensitive and selective NO2 sensors developed by low-cost and scalable fabrication techniques using 2D QC nanosheets and α-Fe2O3 nanoparticles. The sensitivity (ΔR/R%) of the optimal amount of 2D QC nanosheet-loaded α-Fe2O3 sensor was 32%, which is significantly larger about 3.5 times than bare α-Fe2O3 sensors for 1 ppm of NO2 at 150 °C operating temperature. The sensors exhibited p-type conduction, and resistance was reduced when exposed to NO2, an oxidizing gas. The enhanced sensing characteristics are a result of the formation of nanoheterojunctions between 2D QC and α-Fe2O3, which improved the charge transport and provided a large sensing signal. In addition, the heterojunction sensor demonstrated excellent NO2 selectivity over other oxidizing and reducing gases. Furthermore, density functional theory calculation examines the adsorption energy and charge transfer between NO2 molecules on the α-Fe2O3(110) and QC/α-Fe2O3(110) heterostructure surfaces, which coincides well with the experimental results.

Novel Defluorination Pathways of Perfluoroether Compounds (GenX): α-Fe2O3 Nanoparticle Layer Retains Higher Concentrations of Effective Hydrated Electrons.

The development of efficient defluorination technology is an important issue because the kind of emerging pollutant of hexafluoropropylene oxide dimer acid (GenX) as an alternative to perfluorooctanoic acid (PFOA) has the higher environmental risks. In the UV/bisulfite system, we first developed a hydrophobic confined α-Fe2O3 nanoparticle layer rich in oxygen vacancies, which accelerated the enrichment of HSO3- and GenX on the surface and pores through electrostatic attraction and hydrophobic interaction, retaining more hydrated electrons (eaq-) and rapidly destroying GenX under UV excitation. Especially, under anaerobic and aerobic conditions, the degradation percentage of GenX obtain nearly 100%, defluorination of GenX to 88 and 57% respectively. It was amazed to find that the three parallel H/F exchange pathways triggered by the rapid reactions of eaq- and GenX, which were unique to anaerobic conditions, improved the efficiency of fluoride removal and weaken the interference of dissolved oxygen and H+. Therefore, this study provided an available material and mechanism for sustainable fluoride removal from wastewater in aerobic and anaerobic conditions.

Stabilization of γ-Fe2O3 nanoparticles to heat by doping Nb and its property studied by Mössbauer spectroscopy

Nb5+-doped γ-Fe2O3 was synthesized by sol–gel method followed by calcination at various temperatures from 200 to 700 °C, analyzed using Powder X-ray Diffraction (PXRD), Transmission Electron Microscopy (TEM), Energy Dispersive X-ray Spectroscopy (EDS) and Mössbauer Spectroscopy. PXRD results show the formation of γ-Fe2O3 at 300 °C and it begins to transform to α-Fe2O3 at 350 °C for pure and 2 at.% Nb-doped samples. As the Nb doping increases (≥3.8 at.%), the transformation was suppressed up to 600 °C. TEM EDS confirms the incorporation of Nb to γ-Fe2O3 lattice in 9.1 at.% Nb sample calcined at 500 °C. At elevated temperature of 700 °C, γ-Fe2O3 went through full transformation to α-Fe2O3 by expelling large amount of Nb to the surface forming FeNbO4. TEM EDS confirms the compositional change during this process with reduced Nb content in α-Fe2O3 and Nb-rich nanoparticle on the surface of α-Fe2O3. Superparamagnetic properties were observed for Mössbauer spectra when the Nb doping increased, which is caused by decreased particle size. The slight increase in internal magnetic field also indicated the transformation from γ-Fe2O3 to α-Fe2O3. High Nb doping with 20 and 40 at.% shows the formation of FeNbO4 at lower temperature where limited or almost no Nb substitution in α-Fe2O3 was detected by EDS.

Design and construction of a refrigerator-cooled adiabatic calorimeter for heat capacity measurement in liquid helium temperature region.

Heat capacity is a fundamental thermodynamic property of a substance. Although heat capacity values and related thermodynamic functions are available for many materials, low-temperature heat capacity measurements, especially for novel materials, can still provide valuable insights for research in physics, chemistry, thermodynamics, and other fields. Reliable low-temperature heat capacity data are typically measured using classical adiabatic calorimeters, which use liquid helium as the refrigerant to provide a cryogenic environment for heat capacity measurements. However, liquid helium is not only expensive but also not easy to obtain, which greatly limits the application of adiabatic calorimetry. In this work, an accurate adiabatic calorimeter equipped with a Gifford-MacMahon refrigerator was designed and constructed for measuring the heat capacity of condensed matter in the temperature range from 4 to 100K. The Gifford-MacMahon refrigerator was utilized to provide a stable liquid helium-free cryogenic environment. A simple mechanical thermal switch assembly was designed to facilitate switching between the refrigeration mode and the adiabatic measurement mode of the calorimeter. Based on the measurement results of standard reference materials, the optimized repeatability and accuracy of heat capacity measurements were determined to be within 0.8% and 1.5%, respectively. The heat capacity of α-Fe2O3 nanoparticles was also investigated with this device. Furthermore, this adiabatic calorimeter only requires electricity to operate in the liquid helium temperature range, which may significantly advance the research on low-temperature heat capacity based on adiabatic calorimetry.

A Facile Method for Synthesis of α-Fe2O3 Nanoparticles and Assessment of Their Characterization

Recently, magnetic nanomaterials have gained much attention from researchers because of their various unique physical and chemical properties and usage in a wide range of technological aspects. In this study, the synthesis of α-Fe2O3 nanoparticles was performed by a simple co-precipitation method. The synthesis of α-Fe2O3 nanoparticles was carried out by mixing ferric nitrate and oxalic acid in an aqueous solution followed by evaporation, resulting in the solution’s dried form. The synthesized nanoparticles were analyzed by XRD, FTIR, Raman spectra, SEM-EDX, DSC, BET, and Zeta potential for detailed examination of the morphology, structure, and other physicochemical characteristics. The XRD results confirmed that the nanoparticles formed were Hematite (α-Fe2O3) after the evaluation of obtained spectra compared to the Joint Committee on Powder Diffraction Standards Database (JCPDS). The FTIR spectra showed various bonds among functional groups, O-H bending, Fe-O group, and within-vibration bonds. The phase study of the α-Fe2O3 nanoparticles was performed by using Raman spectroscopy. SEM depicted a sphere-like or rhombohedral (hexagonal) structure, and the EDX spectrum confirmed the peaks of iron and oxygen.

Green synthesis, characterization and drug-loaded iron oxide nanoparticles derived from Nerium oleander flower extract as a nanocarrier for in vitro antibacterial efficacy

Application of drug conjugated iron oxide hematite (α-Fe2O3) nanoparticles are of tremendous interest in biomedicine nowadays. Meanwhile, green production of iron oxide nanoparticles is gaining favour due to its sustainability, ease of usage, and biocompatibility. Therefore, this work reports on the use of hexahydrate ferric chloride and nerium oleander flower extract to synthesize nanoscaled hematite (α-Fe2O3) iron oxide particles conjugated with various drugs for antibacterial agents. Diverse morphological, physicochemical, structural, optical, and magnetic characteristics have been characterized using FESEM, EDX, XRD, UV–vis, FTIR, Raman and vibrating sample magnetometer. The synthesis of the polyshaped iron oxide nanoparticles, with average sizes ranging from 47.2 ± 20 nm, was accomplished. Furthermore, temperature-dependent variations in magnetic behavior were observed during calcination. The XRD and Raman spectra revealed hematite (α-Fe2O3) type formation of iron oxide nanoparticles. Only calcinated IO-NPs at high temperatures (700 °C) demonstrated low coercivity and residual magnetism, which revealed weak ferromagnetic ordering; other calcinated samples, including nascent ones, showed incredibly weak ferromagnetic ordering. Besides, the effectiveness of drug-encapsulated iron oxide nanoparticles against bacteria in vitro was examined. It was interesting to observe that gentamycin-coated IO-NPs tended to be more susceptible to S. aureus than E. coli bacteria, but streptomycin-conjugated IO-NPs showed the reverse trend. However, as compared to the nascent sample and the high temperature (700 °C) calcinated sample, both antibiotic-loaded IO-NPs displayed better inhibitory abilities.

Facet-dependent dispersion and aggregation of aqueous hematite nanoparticles.

Nanoparticle aggregates in solution controls surface reactivity and function. Complete dispersion often requires additive sorbents to impart a net repulsive interaction between particles. Facet engineering of nanocrystals offers an alternative approach to produce monodisperse suspensions simply based on facet-specific interaction with solvent molecules. Here, we measure the dispersion/aggregation of three morphologies of hematite (α-Fe2O3) nanoparticles in varied aqueous solutions using ex situ electron microscopy and in situ small-angle x-ray scattering. We demonstrate a unique tendency of (104) hematite nanoparticles to maintain a monodisperse state across a wide range of solution conditions not observed with (001)- and (116)-dominated particles. Density functional theory calculations reveal an inert, densely hydrogen-bonded first water layer on the (104) facet that favors interparticle dispersion. Results validate the notion that nanoparticle dispersions can be controlled through morphology for specific solvents, which may help in the development of various nanoparticle applications that rely on their interfacial area to be highly accessible in stable suspensions.

Ag/α-Fe2O3/g-C3N4 nanocomposites as Z-scheme heterojunction photocatalysts for degradation of RhB

In this study, Ag/α-Fe2O3/g-C3N4 composites with varying α-Fe2O3 and Ag contents were synthesized by loading α-Fe2O3 and Ag nanoparticles onto the g-C3N4 with a high specific surface area via acid annealing. These composites were then utilized for the photocatalytic degradation of RhB under the irradiation of visible light. For α-Fe2O3/g-C3N4 composites with 5 wt% content of α-Fe2O3, the degradation efficiency reached a peak of 97.57% within 55 min, which was much higher than that of α-Fe2O3 and acid-annealed g-C3N4 with 45.92% and 83.61%, respectively. Furthermore, the photocatalytic degradation efficiency of Ag/α-Fe2O3/g-C3N4 composites reached its maximum of 99.61% with 1% content of Ag. It was demonstrated that the ternary Z-scheme heterojunction construction leaded to a significant enhancement of carrier separation and transfer effects, while the incorporation of Ag serves as electron reservoirs and photoinduced electrons capturers, thereby significantly enhancing the Fenton reaction and photocatalytic performance. This work is significant to drive the widespread application of g-C3N4 based heterojunctions in photocatalytic water purification.

Facile formation of surface functionalised α-Fe2O3 nanoparticles and their role in developing dual sensors towards cysteamine quantification

The innovative one step method employed here for the synthesis and surface modification of α-Fe2O3 is equally efficient and viable. The role of surface modification in maximising the output is obvious as terephthalic acid (TPA) crowned Fe2O3 (T-Fe2O3) nanoparticles exhibited better electrochemical properties than bare Fe2O3 when employed as an electrode modifier. It is first time, cysteamine sensors based on T-Fe2O3 nanoparticles were developed and displayed great response in terms of widest linear range, improved selectivity and sensitivity. When combined with glassy carbon electrode (GCE), the sensor achieved broad linear range from 8 µM to 3732 µM which is superior than reported till now. The sensor illustrated with disposable Screen printed electrode (SPE) exhibited widest linear range from 25 to 3900 µM with great linearity in a single calibration graph attributed by the high sensitivity of SPE. The results obtained with SPE lead pathway for designing of portable sensors.

Novel Bi-Functional MoS2/α-Fe2O3 Nanocomposites for High Photocatalytic Performance

In this study, 3-dimensional molybdenum disulfide (MoS2) structures, integrated with hematite (α-Fe2O3) nanoparticles, were fabricated under a convenient two-step hydrothermal route. The fabricated photocatalytic nanocomposites consist of well-arranged MoS2 flakes, resembling spherical flower-like morphology, and the nanoparticulate α-Fe2O3 structures decorate the 3D network. By raising the α-Fe2O3 weight ratio, the composites’ specific surface area and morphology were not affected, regardless of the partial cover of the cavities for higher hematite content. Moreover, the crystallinity examination with XRD, Raman, and FTIR techniques revealed that the precursor reagents were fully transformed to well-crystalized MoS2 and Fe2O3 composites of high purity, as no organic or inorganic residues could be detected. The photocatalytic oxidation and reduction performance of these composites was evaluated against the tetracycline pharmaceutical and the industrial pollutant hexavalent chromium, respectively. The improvement in the removal efficiencies demonstrates that the superior photoactivity originates from the high crystallinity and homogeneity of the composite, in combination with the enhanced charge carriers’ separation in the semiconductors’ interface.

Influence of pH on structural, optical and magnetic properties of undoped and Ni-doped α-Fe2O3 nanoparticles for antimicrobial activity

In this present study, the magnetic and antimicrobial properties of biosynthesized α-Fe2O3 and Ni doped α-Fe2O3 nanoparticles were synthesized from ferric chloride and nickel chloride with the addition of Catharanthus roseus flower extract for different sodium hydroxide concentrations to maintain the pH as 5, 7 and 12. The influence of pH indicates changes observed in the size, structure and crystallinity of the prepared samples. The synthesized nanoparticles were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), UV visible spectroscopy (UV-Vis) and vibrating sample magnetometry (VSM), and their antimicrobial and antioxidant properties were investigated. The XRD analysis revealed the prepared nanoparticles have a rhombohedral hematite structure. FTIR analysis in the range 4000 to 400 cm−1 confirmed the presence of various functional groups for the prepared nanoparticles. The surface morphology and as well as structures of the prepared nanoparticles were confirmed by FESEM. The UV–Vis analysis showed the band gap energies of undoped and Ni-doped α-Fe2O3 nanoparticles. Furthermore, the VSM analysis showed the magnetic properties of undoped and Ni-doped α-Fe2O3 nanoparticles, exhibiting ferromagnetic behaviour at room temperature. The total reducing power of the as-prepared Ni doped α-Fe2O3 nanoparticles was maximum for pH 7, while the antioxidant property was lowered for the remaining samples.The inhibition zone of the prepared nanoparticles showed good antimicrobial activity for pH 7 and showed less inhibition for the other samples against Escherichia coli and Staphylococcus aureus.

Nanocomposites comprising PVA/CMC matrix and CNTs/Fe2O3 nanohybrid: A comparative investigation of structural, optical, electrical, and dielectric properties as an application in advanced electrochemical and optoelectronic devices

This work addresses the fabrication of innovative flexible polymer nanocomposite films for electrochemical products made of poly (vinyl alcohol) (PVA), carboxymethyl cellulose (CMC), multi-walled carbon nanotubes (CNTs), and hematite (α-Fe2O3) nanoparticles (NPs) as nanohybrid. The PVA/CMC-CNTs/Fe2O3 nanocomposite films were characterized using various approaches. The PVA/CMC blend polymer matrix shows significant improvements in terms of amorphous nature with the CNTs/Fe2O3 nanofiller content, resulting in an exceedingly flexible polymer backbone and with higher ionic conductivity of the PVA/CMC-CNTs/Fe2O3 nanocomposites films, as reported by the XRD examination. The nanoparticle surfaces and the blend matrix exhibit a significant interaction, as seen by the FTIR spectra. To learn more about how CNTs/Fe2O3 NPs affect the optical characteristics of the PVA/CMC, its optical characteristics were examined. The absorption edge appeared to migrate towards lower photon energy sides upon the addition of CNTs/Fe2O3 NPs to the PVA/CMC matrix. The Eg (direct and indirect) of pure PVA/CMC was considerably decreased from 5.12 to 3.55 eV and 4.23 to 3.01 eV respectively by adding 3.5 wt% of CNTs/Fe2O3 NPs. The results proved the influence of the nanofiller on the host polymer's decreased band gap energy. The blend nanocomposite had a substantially higher AC conductivity compared with the blend, and the PVA/CMC-3.5%CNTs/Fe2O3 nanocomposite had the highest electrical conductivity. It was discovered that while the dielectric loss and dielectric constant increased with the high content of nanoparticles, they reduced with increasing frequency. These findings demonstrated that the produced films had undergone substantial changes, which allows for the use of flexible films made of PVA/CMC-CNTs/Fe2O3 in a variety of electrochemical and optoelectronic applications.

Chemical/green synthesized cobalt/copper-doped α-Fe2O3 nanoparticles: Potential for environmental remediation

Chemical/green synthesized cobalt/copper-doped α-Fe2O3 nanoparticles: Potential for environmental remediation

Insight into the roles of hematite iron oxide nanoparticles on microalgae growth, urban wastewater treatment and bioproducts generation: Gompertz simulation, nutrient mass balance and gene expression

In this study, the effect of α-Fe2O3 nanoparticles spiking in urban wastewater (UWW) on growth rate, wastewater treatment ability and bioproducts generation of C. vulgaris and Spirulina was investigated and compared with pure cultivation system. The biomass concentration of C. vulgaris and Spirulina improved by 20 % and 39 % at 10 and 15 mg/L α-Fe2O3, respectively while the both microalgae growth pattern fitted better with Gompertz simulation after treatment with α-Fe2O3. The nutrients mass balance revealed that 1 g of treated C. vulgaris and Spirulina could uptake more COD, TN and TP in comparison to the untreated cells. The lipid generation increased remarkably (C. vulgaris: 45 % and Spirulina: 72 %) after α-Fe2O3 treatment. While, the addition of α-Fe2O3 showed no significant impact on the protein and carbohydrate productivity. Overall, this study evangelize the role of nanoparticles on promoting microalgae applications as a sustainable approach for UWW treatment and promising feedstock for biofuel production.

Photocatalytic degradation of methylene blue dye with biosynthesized Hematite α-Fe2O3 nanoparticles under UV-Irradiation

Nanoparticles (NPs) are currently extensively utilized in various fields, such as medicine, solar energy, water treatment, and pollution detection. In this study, hematite (α-Fe2O3) NPs were synthesized using a cost-effective and environmentally friendly method involving the utilization of a biomass filtrate of Mentha pulegium as a bio-reducer. The structural and optical properties of the α-Fe2O3 NPs were investigated using techniques such as X-ray diffraction (XRD), UV-Visible spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). X-ray diffraction analysis confirmed the crystalline nature of the α-Fe2O3 NPs, with a crystallite size ranging from 16.92 to 35.38 nm. The α-Fe2O3 NPs exhibited absorption at 290 nm, indicating a direct bandgap ranging from 3.25 to 3.90 eV and an indirect bandgap of 2.69 to 3.59 eV, as determined from the UV-Visible spectra. FTIR analysis revealed a peak at 486 cm−1, attributed to the vibration of the α-Fe2O3 NPs, confirming the formation of the nanoparticles. SEM imaging showed that the green-synthesized α-Fe2O3 NPs generally exhibited a hexagonal shape. The efficiency of the biosynthesized α-Fe2O3 NPs was evaluated for the rapid degradation of Methylene Blue (MB) dye, achieving a degradation rate of up to 78% after 120 min. These findings could serve as a foundation for the development of highly effective photocatalytic degradation methods that may be employed in the future for the removal of hazardous dyes from contaminated water.

SYNTHESIS, CHARACTERIZATION, AND PHOTOCATALYTIC PROPERTIES OF LANTHANIDE-DOPED HEMATITE NANOPARTICLES

This work aims to develop a highly efficient UV light-induced photocatalyst based on Sm-doped Hematite (α-Fe2O3) nanoparticles (NPs). Sm-doped α-Fe2O3 NPs were synthesized via a straightforward co-precipitation technique and subsequently analyzed for their morphological, structural, and functional attributes. Examination under scanning electron microscopy revealed the formation of NPs, often clustered in small aggregates. Transmission electron microscopy measurements indicated a NPs size range of approximately 18 nm. X-ray diffraction analysis confirmed octahedral-shaped with the crystalline nature and geometry of the synthesized NPs, with a determined crystallite size of 13 nm. The photocatalytic efficacy of the Sm-doped α-Fe2O3 catalysts was evaluated through their ability to degrade Rhodamine B (RhB) under solar light exposure. Remarkably, Sm-doped α-Fe2O3 exhibited outstanding degradation performance, achieving a 96.82% degradation of RhB within 120 minutes under specified conditions ((RhB) = 20 ppm; (catalyst) = 15-25-50 mg/L; pH = 7; T = 30 °C)). The degradation process followed pseudo-first-order kinetics. This exemplary photocatalytic activity suggests that the synthesized NPs hold significant potential for the efficient removal of organic pollutants from industrial wastewater.