Mn Ferrite Nanoparticle Generation in Distilled Water Using Nd:Yttrium Aluminum Garnet Laser H

Mn ferrite nanoparticle generation in distilled water using Nd:yttrium aluminum garnet laser H. R. Dehghanpour and L. Delshad

Citation: Journal of Laser Applications 26, 022008 (2014); doi: 10.2351/1.4866677 View online: http://dx.doi.org/10.2351/1.4866677 View Table of Contents: http://scitation.aip.org/content/lia/journal/jla/26/2?ver=pdfcov Published by the Laser Institute of America

Articles you may be interested in Direct laser writing of three-dimensional photonic structures in Nd:yttrium aluminum garnet laser ceramics Appl. Phys. Lett. 93, 151104 (2008); 10.1063/1.2998258

Mode-locking optimization with a real-time feedback system in a Nd:yttrium lithium fluoride laser cavity Rev. Sci. Instrum. 78, 013105 (2007); 10.1063/1.2356853

Enhanced 532 nm emission by frequency-doubling of the one-micron Nd:yttrium vanadate laser in gadolinium calcium oxoborate J. Appl. Phys. 97, 056104 (2005); 10.1063/1.1851594

Ultraviolet single-frequency pulses with high average power using frequency-converted passively Q-switched quasimonolithic Nd:yttrium–aluminum–garnet ring lasers Appl. Phys. Lett. 79, 458 (2001); 10.1063/1.1388028

Highly efficient 2% Nd:yttrium aluminum garnet ceramic laser Appl. Phys. Lett. 77, 3707 (2000); 10.1063/1.1331091

This article is copyrighted as indicated in the article. Reuse of AIP content is subject to the terms at: http://scitation.aip.org/termsconditions. Downloaded to IP: 67.180.227.126 On: Mon, 07 Apr 2014 05:28:32 JOURNAL OF LASER APPLICATIONS VOLUME 26, NUMBER 2 MAY 2014

Mn ferrite nanoparticle generation in distilled water using Nd:yttrium aluminum garnet laser H. R. Dehghanpoura) and L. Delshad Physics Department of Tafresh University, Tafresh, Markazi 3951879611, Iran (Received 5 October 2012; accepted for publication 5 February 2014; published 31 March 2014) In this work, the authors have generated Mn ferrite nanoparticles by Nd:YAG (1064 nm) laser irradiation in distilled water. Then, they have investigated shape and size of nanoparticles by transmission electron microscopy and atomic force microscope. Chemical composition of nanoparticle was characterized using dispersive x-ray energy, and the magnetic properties of them were studied by magnetic force microscopy. A spinel structure in nanoparticles similar to the bulk sample was shown by selected area electron diffraction. The results show that the chemical composition and magnetic properties of nanoparticles are nearly similar to bulk sample. VC 2014 Laser Institute of America.[http://dx.doi.org/10.2351/1.4866677]

Key words: magnetic nanoparticle, Mn ferrite, laser

I. INTRODUCTION distilled water so that 6 mm of liquid height was above the target at room temperature using a lens with 10 cm focal point. Study of the magnetic materials is a rich mixture of syn- The focusing area, power, and energy density of laser were thesis, characterization, theory, and applications.1 Magnetic controlled properly by the relative displacement of the target nanoparticles are needed in ferro-ﬂuids,2 refrigeration sys- and the lens. The exposure times were performed on 10 min. tems,3 and multiterabit information storage devices.4,5 The After laser irradiation, drops of liquid containing nanoparticles nanoparticles of metal oxides such as soft ferrites are attrac- were placed on a plate of glass using pipette. Then, after water tive because of their properties by chemical manipulations.6 evaporation, we have collected remained materials. The magnetic properties of ferrites are strongly changed when the particle size is near to the critical diameter so that B. Characterization methods below it each particle is a single magnetic domain.7 Laser ablation which is usually applied to in situ elemen- Geometrical aspects of the generated nanoparticles were tal analysis,8 forming thin ﬁlm (pulsed laser deposition)9 has studied by transmission electron microscopy (TEM), Philips been also used to prepare nanoparticles.10,11 model EM 208 S, and atomic force microscope (AFM), Here, we have generated Mn ferrite nanoparticles in dis- Dualscope/Rasterscope C26 DME Denmark. Chemical com- tilled water by Q-switched Nd:YAG laser (1064 nm) irradia- position of the bulk and nanoparticles was investigated using tion on the Mn ferrite target. Then, the geometrical, energy-dispersive x ray (EDX). Magnetic properties of these chemical, and magnetic properties of those nanoparticles samples were measured by magnetic force microscope were investigated properly. (MFM), Dualscope/Rasterscope C26 DME Denmark.

II. EXPERIMENTAL SECTION III. RESULTS AND DISCUSSIONS A. Synthesis methods TEM can yield information such as size and size distribution as well as morphology of the nanoparticles. In particle Figure 1 shows the schematic diagram of the experimen- size measurement, microscopy is the only method in which tal setup. Mn ferrite target was immersed in distilled water individual particles are directly observed and measured.12 and ﬁxed on the plate connected to motor to rotate Usually, the calculated sizes are reported as the diameter of a (5 rev/min) the target to prevent laser irradiation on the same sphere that has the same projected area as the projected spot. Nanoparticles were generated by pulsed nanosecond laser irradiation of a Q-switched Nd:YAG laser (Brio 2008) at 1064 nm. The laser pulses are characterized with 10 ns du- ration, 5 Hz repetition rate, 60 mJ energy per pulse, 6 J/cm2 energy density with 1 mm spot size on the target. The laser beam was focused on a target of 2 mm thickness. It was situ- ated at the bottom of a glass beaker ﬁlled with 10 ml of

a)Author to whom correspondence should be address. Electronic mail: [email protected]; Also at: Photonic Research Group, Tafresh FIG. 1. Experimental setup for fabricating Mn ferrite nanoparticles in dis- University, Tafresh, Iran. tilled water by laser irradiation.

1042-346X/2014/26(2)/022008/4/$28.00 022008-1 VC 2014 Laser Institute of America

This article is copyrighted as indicated in the article. Reuse of AIP content is subject to the terms at: http://scitation.aip.org/termsconditions. Downloaded to IP: 67.180.227.126 On: Mon, 07 Apr 2014 05:28:32 022008-2 J. Laser Appl., Vol. 26, No. 2, May 2014 H. R. Dehghanpour and L. Delshad

FIG. 2. TEM micrograph of Mn ferrite generated nanoparticles by Nd:YAG laser with 10 min exposure time.

image of the particle. Manual or automatic techniques are FIG. 4. SAED patterns of the nanoparticles fabricated by 10 min Q-switched Nd:YAG irradiation. used for particle size analysis. Manual technique is usually based on the use of a marking device moved along particle Selected area electron diffraction (SAED) of the nano- to obtain a linear dimensional measure of particle added up 13 particles generated by 10 min Nd:YAG exposure time is and divided by the number of particles to get a mean result. shown in Fig. 4. The first three rings’ diameters were meas- In combination with diffraction studies, microscopy becomes 14 ured. Half of each diameter gives us the ring radius accord- a very valuable aid to characterize nanoparticles. TEM ing to the camera constant equation, as below images of Mn ferrites nanoparticles generated by Q-switched Nd:YAG laser on the exposure time 10 min as well as corre- d ¼ kL=R; sponding size distributions are shown in Fig. 2. By using of scale bar of Fig. 2 and a millimeter ruler, we have measured where d, k,L, and R are lattice spacing, wavelength of accel- the diameter of each spherical particle. Then, we have col- erating voltage, camera length, and ring radius, respectively. lected the data and show them in Fig. 3. After the laser is The product kL is called camera constant. The lattice spacing switched off, the fragmentation process stops and the aggre- d is determined by dividing the camera constant by R, which gation process develops. TEM image shows nearly spherical is the radius measured as mentioned above. nanoparticles with mean diameter of 28.5 nm. Taking into Table I corresponds to the calculated lattice spacing, account the process of formation of nanoparticles and rapid according to crystal reflection and true lattice spacing. Good quenching of the ablated material into the liquid, this is their 15 agreement between exact lattice spacing and calculated most probable morphology. lattice spacing verifies that the samples generated by Although some of authors believe that the largest par- Q-switched Nd:YAG laser have spinel crystalline structure ticles most likely result from the aggregation of the smaller 16 similar to the bulk sample. particles afterward, it can be mentioned that an aggregate The results of EDX microanalyses of the bulk sample particle is not necessarily a particle in its own right. On the and nanoparticles are collected in Tables II and III, other hand, although the number of large particle is small, if respectively. it is made of many small particles, surely statistics do As a result, although the chemical composition of the change. It is in contrast with the opinion that expresses the target and nanoparticles are the same, the percentages of ele- number of large particle is relatively small and does not 16 ments have a few deviations. Those deviations are not signif- influence significantly the size distribution. icant except for oxygen. We believe that considerable oxygen increasing in the nanoparticles is due to increase in the surface areas of the nanoparticles compared to bulk sample which results more surface oxygen content bonds. So the laser ablation could not effect on the cubic structure of nanoparticles. Although TEM is the most extensively used experimental technique to obtain general information on particle

TABLE I. Characterization of the nanoparticles using electron diffraction rings.

Ring Radius Experimental Exact spacing number (R) (mm) spacing (d) (nm) (d) (nm) Reflection

1 27 0.2110 0.2130 h400i 2 33 0.1720 0.1750 h422i FIG. 3. Size distribution of Mn ferrite nanoparticles generated by 10 min 3 45 0.1260 0.1240 h444i Nd:YAG exposure time.

This article is copyrighted as indicated in the article. Reuse of AIP content is subject to the terms at: http://scitation.aip.org/termsconditions. Downloaded to IP: 67.180.227.126 On: Mon, 07 Apr 2014 05:28:32 J. Laser Appl., Vol. 26, No. 2, May 2014 H. R. Dehghanpour and L. Delshad 022008-3

TABLE II. Results of EDX for bulk sample. between 4 and 70 nm with the average near 30 nm. These results have ignorable differences with TEM ones (Fig. 3). It Element C O Mn Fe Si may be raised due to the assumption of the spherical shape of 17 W% 4.23 37.76 21.57 32.5 3.94 the nanoparticles. MFM can provide useful information A% 14.06 56.81 14.98 12.62 1.43 about local magnetic structure as well as topographical properties under the influence of external magnetic fields.18 MFM images are created by scanning the attractive and repulsive TABLE III. Results of EDX for nanoparticles (10 min exposure time). magnetostatic field with the interactions between the shape of the magnetic tip in the vertical direction and the surface of the Element C O Mn Fe Si sample in the horizontal position.19 The shifts of the tips under the magnetization of the sample are displayed on MFM images W% 2.17 58.26 12.26 25.12 2.19 A% 4.34 78.7 5.49 10.68 0.79 by dark and bright regions, e.g., the dark regions demonstrate large negative shifts (repulsion) and the bright regions demonstrate large positive shifts (attraction).20 Figure 6 depicts MFM image of 5 lm 5 lm area of Mn ferrite nanoparticles.

IV. CONCLUSION In this work, we have examined the laser nanoparticle generation in liquid method for fabrication ceramic magnetic nanoparticles. Aggregation of the particles created occurs after a certain period of time (several minutes), as a result of aging. Generated nanoparticles had spinel crystalline structure similar to the bulk sample. On the other hand, the per- centage of elements in the nanoparticles and bulk sample is nearly the same. Magnetic property of the nanoparticles was detectable. It is worth noting that investigation of changing laser dose, wavelength, and exposure time has important role to complete this work.

1J. M. D. Coey, “Magnetism in future,” J. Magn. Magn. Mater. 226–230, 2107 (2001). 2Y. Sahoo, A. Goodarzi, M. T. Swihart, T. Y. Ohulchaskyy, N. Kaur, E. P. Furlani, and P. N. Prasad, “Aqueous ferroﬂuid of magnetite nanoparticles: Fluorescence labeling and magnetophoretic control,” J. Phys. Chem. B 109, 3879 (2005). FIG. 5. AFM image of generated Mn ferrite nanoparticles. 3R. D. Shull, “Magnetocaloric effect of ferromagnetic particles,” IEEE Trans. Magn. 29, 2614 (1993). 4X. Sun, Y. Huang, and D. E. Nikles, “FePt and CoPt magnetic nanoparticles ﬁlm for future high density data storage media,” Int. J. Nanotechnol. 1, 328 (2004). 5T. Hyeon, “Chemical synthesis of magnetic nanoparticles,” Chem. Commun. 927 (2003). 6Q. Chen and Z. J. Zhang, “Size-dependent superparamagnetic properties of MgFe2O4 spinel ferrite nanocrystallites,” Appl. Phys. Lett. 73, 3156 (1998). 7D. K. Kim, Y. Zhang, W. K. Voit, V. Rao, and M. Muhammed, “Synthesis and characterization of surfactant-coated superparamagnetic monodis- persed iron oxide nanoparticles,” J. Magn. Magn. Mater. 225, 30 (2001). 8T. Nishi, T. Sakka, H. Oguchi, K. Fukami, and Y. H. Ogata, “In situ elec- trode surface analysis by laser-induced breakdown spectroscopy,” J. Electrochem. Soc. 155(11), F237–F240 (2008). 9M. Z. Xue and Z. W. Fu, “Electrochemical reactivity mechanism of CuInSe2 with lithium,” Thin Solid Films 516, 8386 (2008). 10S. C. Singh and R. Gopal, “Laser irradiance and wavelength-dependent compositional evolution of inorganic ZnO and ZnOOH/organic SDS nano- composite material,” J. Phys. Chem. C 112, 2812 (2008). 11T. Okada and J. Suehiro, “Synthesis of nano-structured materials by laser- ablation and their application to sensors,” Appl. Surf. Sci. 253, 7840 FIG. 6. MFM image of generated Mn ferrite nanoparticles. (2007). 12T. Allen, Particle Size Measurement, 5th ed. (Chapman and Hall, Great Britain, Padstow, Cornwall, 1997), Vols. 1 and 2. morphology and evaluate size distribution, AFM method has 13A. Jilavenkatesa, S. J. Dapkunas, and H. L. Lin-Sien, “Particle size charac- been established as a complementary and very useful method terization,” in NIST Recommended Practical Guide (National Institute of Standards and Technology (Natl. Inst. Stand. Technol.), USA, 2001). for characterization of shapes in nanoworld. Figure 5 shows 14A. Rawle, “The importance of particle sizing to the coatings industry Part AFM images of nanoparticles. The particle size is comprised 1: Particle size measurement,” Adv. Color Sci. Technol. 5, 1 (2005).

This article is copyrighted as indicated in the article. Reuse of AIP content is subject to the terms at: http://scitation.aip.org/termsconditions. Downloaded to IP: 67.180.227.126 On: Mon, 07 Apr 2014 05:28:32 022008-4 J. Laser Appl., Vol. 26, No. 2, May 2014 H. R. Dehghanpour and L. Delshad

15C. H. Liang, A. W. Colightly, and J. R. Castleman, “Analysis of titanium 18S. A. Koch, R. H. Velde, G. Palasantza, and J. T. M. D. Hosson, nanoparticles created by laser irradiation under liquid environments,” “Magnetic force microscopy on cobalt nanocluster ﬁlms,” Appl. Surf. Sci. J. Phys. Chem. B 110, 19979 (2006). 226, 185 (2004). 16X. P. Zhu, T. Suzuki, T. Nakayama, H. Suematsu, W. Jiang, and K. 19J. Santoyo-Salazar, M. A. Castellanos-Roman, and L. B. Gomez, Niihara, “Underwater laser ablation approach to fabricating monodisperse “Structural and magnetic domains characterization of magnetite nano- metallic nanoparticles,” Chem. Phys. Lett. 427, 127 (2006). particles,” Mater. Sci. Eng. C 27, 1317 (2007). 17M. Vujtek, R. Kubinek, R. Zboril, and L. Machala, Modern Research and 20H. Takahoshi, H. Saito, and S. Ishio, “MFM analysis of magnetization pro- Educational Topics in Microscopy (FORMATEX, Spain, 2007). cess in CoPt dot-array,” J. Magn. Magn. Mater. 272–276, e1313 (2004).