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Synthesis and magnetic properties of PrFeO3 nanopowders by the co-precipitation method using ethanol
A. T. Nguyen1, V. Y. Nguyen2'3, I. Ya. Mittova4, V. O. Mittova5, E.L. Viryutina4, C. Ch. T. Hoang1, Tr. L. T. Nguyen1, X. V. Bui6, T. H. Do7
1Ho Chi Minh City University of Education, Ho Chi Minh City, 700000, Vietnam 2Institute of Theoretical and Applied Research, Duy Tan University, Ha Noi, 100000, Vietnam 3Faculty of Natural Sciences, Duy Tan University, Da Nang, 550000, Vietnam 4Voronezh State University, Universitetskaya pl.1, Voronezh, 394018, Russia 5Burdenko Voronezh State Medical University, Voronezh, 394036, Russia 6Faculty of Pedagogy in Natural Sciences, Sai Gon University, Ho Chi Minh City, 700000, Vietnam 7Thai Nguyen University of Education, Thai Nguyen University, Vietnam tienna@hcmue.edu.vn, nguyenvanyen@duytan.edu.vn, imittova@mail.ru, vmittova@mail.ru, viryutina.helena@yandex.ru,htcamchuong92@gmail.com, linhntt@hcmue.edu.vn, buixuanvuongsgu@gmail.com, huongdt.chem@tnue.edu.vn
DOI 10.17586/2220-8054-2020-11-4-468-473
Praseodymium orthoferrite nanoparticles were synthesized by a simple co-precipitation method via the hydrolysis of Pr (III) and Fe (III) cations in boiling ethanol with 5% aqueous ammonia. The single-phase PrFeO3 product formed after annealing the precipitates at 650, 750, and 850°C for 1 h had an average crystal size of 20-30 nm (XRD, SEM, TEM). The synthesized nanopowders were soft ferromagnetic materials with low coercive force and excessive magnetization values.
Keywords: o-PrFeO3, nanoparticles, magnetic properties, co-precipitation, ethanol. Received: 28 May 2020 Revised: 29 June 2020
1. Introduction
Among semiconductors, oxides with a perovskite-like structure of the ReMeO3 type (Re - rare-earth elements; Me - transition metals) have both significance and importance for their application and fundamental research [1-8], since these oxides have a high sensitivity of properties to decrease in particle size to nanometer values. Among the rare-earth orthoferrites, PrFeO3 was obtained and used in some fields, such as magneto-optical devices and electromagnetic equipment [9-13], photocatalysts [14-16], dyes, and inorganic pigments [17,18].
A wide variety of techniques have been developed for the synthesis of praseodymium orthoferrite nanoparticles (o-PrFeO3), for example, high-temperature ceramic fabrication [9,11,18], hydrothermal methods [13,16], and solgel complex methods [14,15,17,19]. Several studies [20-25] describe the formation of ReFe1-xMxO3 orthoferrites nanoparticles (Re = Nd, Y, La; M = Mn, Co, Ni), by a simple co-precipitation method in boiling water followed by the addition of appropriate precipitants. According to published data, the replacement of water as a solvent with ethanol for the synthesis of o-PrFeO3 nanoparticles was not studied.
The goal of this study the synthesis of praseodymium orthoferrite (o-PrFeO3) nanoparticles with low coercive force and excessive magnetization by co-precipitation via hydrolysis of praseodymium (III) and iron (III) cations in boiling ethanol with the addition of an ammonia solution.
2. Experimental
In this study, we used Pr(NO3)3 6H2O, Fe(NO3)3 9H2O, absolute ethanol (d=0.79 g/ml), 25 % ammonia solution (d=0.901 g/ml) (all reagents were of CP grade), distilled water. The procedure for PrFeO3 nanoparticles synthesis was similar to that of ReFeO3 (Re = Nd, Y, La) nanomaterials [20,21], with ethanol as the solvent instead of water.
Complex thermal analysis of the PrFeO3 sample was carried out TG-DSC analyzer (Labsys Evo, TG-DSC 1600°C, SETARAM Instrumentation). The sample was placed in a platinum cylindrical crucible and heated from 30 to 1000°C at 10 K min-1 in dried air. X-ray phase analysis was carried out on a D8-ADVANCE diffractome-ter (CuKa radiation, A = 0.15418 A). The qualitative and quantitative elemental composition was established using a local X-ray spectral microanalysis (EDX, Horiba H-7593. Particle size and morphology were determined using
scanning electron microscopy (FESEM S-4800) and high voltage transmission electron microscopy (HRTEM; JEOL-1400). The average crystal size was determined according to the Debye Scherrer equation; parameters a, b, c and the unit cell volume V were determined using the Rietveld method, implemented in the X'pert High Score Plus 2.2b software package.
The magnetic characteristics of PrFeO3 nanopowders (coercive force Hc, remanent magnetization Mr, and magnetization Ms) were studied using vibrating sample magnetometer at room temperature (VSM, MICROSENE EV11).
3. Results and discussions
The complex thermal analysis of the dried precipitate showed (Fig. 1) that the mass loss during heating of the sample in the range of 60-1000°C was 27.01 %. The most significant mass loss (about 25.85 %) was observed in the range of 50-600°C. The processes occurring during heating of the precipitate were accompanied by three endothermic thermal effects at 93.38, 327.62, and 420.78°C (Fig. 1), characteristic for water evaporation, decomposition of iron (III) hydroxides and praseodymium (III) (20, 26 In the 600-700°C range, an exothermic thermal effect (636.10°C, Fig. 1) was observed corresponding to the formation of perovskite PrFeO3.
Fig. 1. TG-DSC curves of the powders prepared by a simple co-precipitation method using ethanol
In accordance with the data of complex thermal analysis for the synthesis of praseodymium orthoferrite, the temperatures of 650, 750 and 850° C were chosen to calcine the precipitate for 1 h. XRD patterns of the samples annealed at 650, 750, and 850°C for 1 h showed single-phase orthoferrite PrFeOs (JCPDC No 00-047-0065) (Fig. 2). The average crystal diameter and cell volume of PrFeO3 samples increase with increasing annealing temperature, (Table 1).
According to the results of local X-ray spectral microanalysis, PrFeO3 sample contained only three elements -Pr, Fe, and O (Fig. 4). Mass percentage and elemental percentage of obtained PrFeO3 nanopowders are rather close to expected chemical composition (Fig. 4). It can be seen from SEM, TEM, and HRTEM images (Fig. 5) that, after annealing at 750° C for 1 h, PrFeO3 nanoparticles were isometric, and the average size of individual particles was about 30 nm. Interestingly, the synthesized PrFeO3 nanoparticles were characterized by a lower degree of agglomeration compared to the orthoferrites of other rare-earth elements, such as NdFeO3 [20], YFeO3 [21], and LaFeO3 [25], obtained by the co-precipitation method via the hydrolysis of cations in boiling water. This was explained by the fact that a lower polarity of ethanol than water (the dipole moments of water and ethanol are 1.85 and 1.66 D, respectively [26,27]) led to an insignificant interaction between the cations of iron (III) and praseodymium (III) with
Fig. 2. XRD patterns of PrFeO3 nanopowders annealed at 650, 750, and 850oC for 1 h
Fig. 3. Slow-scan XRD patterns of peak (121) of PrFeO3 nanopowders annealed at 650, 750, and 850o C for 1 h
FIG. 4. EDX image of PrFeÛ3 sample annealed at 750oC for 1 h
fig. 5. SEM (a), TEM (b), and HRTEM (c) images of PrFeÜ3 nanoparticles annealed at 750°C for 1 h
ra-
Й-
— r ,1:
[1)-№0 (=Q
(2). -750 (°C)
P)—S50f°C)
n-1-1-1-1-1-1-1-г
-5030 -2500 0 2500 5000
Field (Oe>
Fig. 6. Field dependence of the magnetization of PrFeÛ3 nanopowders, annealed at 650, 750, and 850o C for 1 h
TABLE 1. XRD patterns of PrFeO3 nanopowders annealed at 650, 750, and 850°C for 1 h
Indices PrFeO3
650° C 750°C 850° C
a, A 5.4576 5.4732 5.4513
b, A 5.5742 5.5831 5.6207
c,A 7.8110 7.7995 7.8178
Volume, A3 237.62 238.33 239.54
Average crystal diameter, nm 19.73 22.37 25.48
Coercive force Hc, Oe 17.45 29.45 33.38
Remanent magnetization Mr, emu/g 0.4410-3 1.1010-3 1.77-10-3
Magnetization M, emu/g 0.11 0.12 0.14
ethanol molecules. Accordingly, the formed sediment particles were more easily separated from each other and from the solvent.
The study of PrFeO3 samples using the magnetometer MICROSENE EV11 at 300 K in a maximum field of 5000 Oe showed that all certain magnetic characteristics Hc, Mr and Ms (Fig. 6, Table 1). Probably, this was due to the fact that annealing at a higher temperature led to larger PrFeO3 particles (Table 1). Nanoscale particles (D < 100 nm) can be considered as single-domain particles. Then, Hc depends on the particle size according to the following formula [28]:
Hc = g - D3/2 (1)
where g and h are constants, and D is the particle diameter. Clearly, Hc will increase with the particle size. Indeed, when the crystallite size rises from 19.73 to 25.48 nm, Hc also increases from 17.45 to 33.38 Oe. A similar pattern was observed in [25]. It is more interesting that the synthesized PrFeO3 nanocrystals were characterized by lower Hc and Mr values, but higher Ms at 300 K compared to the orthoferrite particles of other rare-earth elements, such as HoFeO3 (Hc=2659 Oe, Mr =4.08, [29]), LaFeO3 (Hc=1217.6 Oe, Mr=5.4310-4 emu/g, Ms=6.4910-3 emu/g, [30]), NdFeO3 (Hc -850 Oe, Mr=1.5 emu/g, [31]) and even o-PrFeO3 (Ms=0.05 emu/g, [13]).
The studied o-PrFeO3 samples with low values of coercive force, excess magnetization, and higher magnetization not reaching magnetic saturation at a maximum field of 5000 Oe were a soft magnetic ferromagnet and can be used for the manufacture of magnetic cores, transformers, electric motors, and generators.
4. Conclusion
In this study, o-PrFeO3 nanoparticles with an average crystal size < 30 nm were formed by co-precipitation method by aqueous ammonia solution via simple process of the hydrolysis of Pr (III) and Fe (III) cations in boiling ethanol, followed by annealing at 650, 750, and 850°C for 1 h. The synthesized o-PrFeO3 nanopowders were characterized by a narrow hysteresis loop, low values of excess magnetization and coercive force, but high magnetization, which makes them promising for use as soft ferromagnetic material in the manufacture of magnetic cores, transformers, electric motors, generators, and radio engineering.
Conflict of interests
The authors maintain that they have no conflict of interest with respect to this communication.
Acknowledgements
Nguyen Anh Tien thanks the financial support of Ho Chi Minh City University of Education, Ho Chi Minh City, Vietnam through Grant No. CS.2019.19.19.
References
[1] Popkov V.I., Almjasheva O.V., Nevedomskii V.N., Panchuk V.V., Semenov V.G., Gusarov V.V. Effect of spatial constraints on the phase evolution of YFeOe-based nanopowders under heat treatment of glycine-nitrate combustion products. Ceramics International, 2018, 44(17), P. 20906-20912.
[2] Bachina A., Ivanov V.A., Popkov V.I. Peculiarities of LaFeO3 nanocrystals formation via glycine-nitrate combustion, Nanosystems: Physics, Chemistry, Mathematics, 2017, 8(5), P. 647-653.
[3] Shanker J., RaoG.N., VenkataramanaK., BabuD.S., Investigation of structural and electrical properties of NdFeO3 perovskite nanocrystalline. Physics Letter A, 2018, 382(4), P. 2974-2977.
[4] H. El Moussaoui, Mounkachi O., Masrour R., Hamedoun M., Hlil E.K., Benyoussef A. Synthesis and super-paramagnetic properties of neodymium ferrites nanorods. Journal of Alloys and Compounds, 2013, 581, P. 776-781.
[5] Zh.-Qi. Wang, Ya.-Sh. Lan, Zh.-Yi. Zeng, X-R. Chen, Q-.-F. Chen. Magnetic structures and optical properties of rare-earth orhtoferrites RFeO3 (R = Ho, Er, Tm and Lu). Solid State Communications, 2018.
[6] Jeffrey W. Fergus, Perovskite oxides for semiconductor-based gas sensors. Sensors and Actuators B: Chemical, 2007, 123(2), P. 1169-1179.
[7] Popkov V.I., Tugova E.A., Bachina A.K., Almjasheva O.V. The formation of nanocrystalline orthoferrites of rare-earth elements XFeO3 (X = Y, La, Gd) via heat treatment of co-precipitated hydroxides. Russian Journal of General Chemistry, 2017, 87(11), P. 1771-1780.
[8] Kondrashkova I.S., Martinson K.D., Zakharova N.V., Popkov V.I. Synthesis of nanocrystalline HoFeO3 photocatalyst via heat treatment of products of glycine-nitrate combustion. Russian Journal of General Chemistry, 2018, 88(12), P. 2465-2471.
[9] Abdellahi M., Abhari A.Sh., Bahmanpour M. Preparation and characterization of orthoferrite PrFeO3 nanoceramic. Ceramics International, 2016, 42(4), P. 4637-4641.
[10] Sultan K., Ikram M., Asokan K. Structural, optical and dielectric study of Mn doped PrFeO3 ceramics. Vacuum, 2014, 99, P. 251-258.
[11] Panchwanee A., Reddy V.R., Gupta A. Electrical and Mossbauter study of polycrystalline PrFeO3. Journal of Physics: Conference Series, 2016, 755, P. 012033.
[12] Mir F.A., Sharma S.K., Ravi Kumar. Magnetization and magneto-transport properties of Ni-doped PrFeO3 thin film. Chinese Physics B, 2014, 23(4), P. 048101.
[13] Zhou Zh., Guo L., Yang H., Liu Q., Ye F. Hydrothermal synthesis and magnetic properties of multiferroic rare-earth orthoferrites. Journal of Alloys and Compounds, 2014, 583, P. 21-31.
[14] Tijare S.N., Bakardjieva S., Subrt J., Joshi M.V., Rayalu S.S., Hishita S., Labhsetwar N. Synthesis and visible light photocatalytic activity of nanocrystalline PrFeO3 perovskite for hydrogen generation in ethanol-water system. Journal of Chemical Sciences, 2014,126(2), P. 517-525.
[15] Peisong T., Xinyu X., Haifeng Ch., Chunyan L., Yangbin D., Synthesis of nanoparticulate PrFeO3 by sol-gel method and its visible-light photocatalytic activity. Ferroelectrics, 2019, 546, P. 181-187.
[16] Megarajan S.K., Rayalu S., Nishibori M., Labhsetwar N. Improved catalytic activity of PrMO3 (M = Co and Fe) perovskite: synthesis of thermally stable nanoparticles by a novel hydrothermal method, New Journal Chemistry, 2015, 39, P. 2342-2348.
[17] Opuchovic O., Kreiza G., Senvaitiene J., Kazlauskas K., Beganskiene A., Kareiva A. Sol-gel synthesis, characterization and application of selected sub-microsized lanthanide (Ce, Pr, Nd, Tb) ferrites. Dyes and Pigments, 2015,118, P. 176-182.
[18] Luxova J., SulcovaP., Trojan M. Influence of firing temperature on the color properties orthoferrite PrFeO3. Thermochimica Acta, 2014, 579, P. 80-85.
[19] Pekinchak O., Vasylechko L., Lutsyuk I., Vakhula Ya., Prots Yu., Carrillo-Cabrela W. Sol-gel-prepared nanoparticles of mixed praseodymium cobaltites-ferrites. Nanoscale Research Letters, 2016, 11(75).
[20] Nguyen T.A., Pham V., Pham T.L., Nguyen L.T.Tr., Mittova I.Ya., Mittova V.O.,Vo L.N., Nguyen B.T.T., Bui V.X., Viryutina E.L. Simple synthesis of NdFeO3 by the so-precipitation method based on a study of thermal behaviors of Fe (III) and Nd (III) hydroxides. Crystals, 2020, 10, P. 219.
[21] Nguyen A.T., Almjasheva,O.V. Mittova I.Ya., Stognei O.V., Soldatenko S.A. Synthesis and magnetic properties of YFeO3 nanocrystals. Inorganic Materials, 2009, 45(11), P. 1304-1308.
[22] Nguyen A.T., Mittova I.Ya., Almjasheva O.V., Kirillova S.A., Gusarov V.V. Influence of the precipitation conditions on the size and morphology of nanocrystalline lanthanum orthoferrite. Glass Physics and Chemistry, 2008, 34(6), P. 756-761.
[23] Nguyen A.T., Vinh N.T. Pham, Nguyen T.Tr.L., Mittova V.O., Vo Q.M., Berezhnaya M.V., Mittova I.Ya., Do Tr.H., Chau H.D. Crystal structure and magnetic properties of perovskite YFe1_xMnxO3 nanopowders synthesized by co-precipitation method. Solid State Sciences, 2019, 96, P. 105922.
[24] Nguyen A.T., Chau H.D., Tr.L. Nguyen Thi, Mittova V.O., Do Tr.H., Mittova I.Ya. Structural and magnetic properties of YFe1-xCoxO3 (0.1 < x < 0.5) perovskite nanomaterials synthesized by co-precipitation method. Nanosystems: Physics, Chemistry, Mathematics, 2018, 9(3), P. 424-429.
[25] Tien A. Nguyen, Vinh N.T. Pham, Hanh T. Le, Diem H. Chau, Mittova V.O., Linh T.Tr. Nguyen, D.A. Dinh, T.V. Nhan Hao, I.Ya. Mittova. Crystal structure and magnetic properties of LaFe1-xNixO3 nanomaterials prepared via a simple co-precipitation method. Ceramics International, 2019, 45, P. 21768-21772.
[26] Housecroft C.E., Sharpe A.G. Inorganic Chemistry, second ed., Pearson, Prentice Hall, 2005.
[27] David Klein. Organic Chemistry, 2-nd edition, Wiley, 2016, chapte 13.
[28] Cullity B.D., Graham C.D. Introduction to Magnetic Materials. John Wiley and Sons, Piscataway, NJ, 2011.
[29] Habib Z., Majid K., Ikram M., Sultan Kh. Influence of Ni subsmitution at B-site for Fe3+ ions on morphological, optical, and magnetic properties of HoFeO3 ceramics. Applied Physics A. Materials Science & Processing, 2016, 122(550).
[30] Sasikala C., Durairaj N., Baskaran I., Sathyaseelan B., Henini M. Transition metal titanium (Ti) doped LaFeO3 nanoparticles for enhanced optical structure and magnetic properties. Journal of Alloys and Compounds, 2017, 712, P. 870-877.
[31] Babu P.R., Babu R. Starch assisted sol-gel synthesis and characterization of NdFeO3. International Journal of ChemTech Research, 2016, 9(4), P. 364-369.
