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2nd International Conference on Materials Manufacturing and Design Engineering 2nd International Conference on Materials Manufacturing and Design Engineering

Sol-gel Auto Combustion Synthesis, Structural and Magnetic Sol-gel Auto Combustion Synthesis, Structural and Magnetic Properties of Mn doped Conference ZnO Nanoparticles Manufacturing Engineering Society International 2017, MESIC 2017, 28-30 June Properties of Mn doped ZnO Nanoparticles 2017, Vigo (Pontevedra), Spain

Shankar D. Birajdaraa *, R. C. Alangebb, S. D. Morecc, V. D. Murumkardd, K. M. Jadhavee Shankar D. Birajdar *, R. C. Alange , S. D. More , V. D. Murumkar , K. M. Jadhav

of Basicfor Sciencecapacity and Humanities, Marathwada Institute of Technology (MIT), Aurangabad, (M.S), India CostingDepartment models optimization in Industry 4.0: Trade-off Department of Basic Science and Humanities, Marathwada Institute of Technology (MIT), Aurangabad, (M.S), India Department of Physics, Shri Madhavrao Patil Mahavidyalaya, Murum, Osmanbad, (M.S), India Department ofMadhavrao Physics, Deogiri College Aurangabad, (M.S), India between capacity and operational efficiency Department ofused Physics, Shri Patil Mahavidyalaya, Murum, Osmanbad, (M.S), India a a

b b

c

c Department of Physics, Deogiri College Aurangabad, (M.S), India Aurangabad, (M.S), India Department of Physics, Vivekanand Arts, Sardar Dalip Sing Commerce and Science College, d e Department of Physics, Arts, Sardar Dalip Sing Commerce and Science College, Aurangabad, (M.S), India Department of Vivekanand Physics, Dr.Babasaheb Ambedkar Marathwada University, Aurangabad, a a,* b b(M.S), India e Department of Physics, Dr.Babasaheb Ambedkar Marathwada University, Aurangabad, (M.S), India d

A. Santana , P. Afonso , A. Zanin , R. Wernke a

University of Minho, 4800-058 Guimarães, Portugal

Unochapecó, 89809-000 Chapecó, SC, Brazil Abstract Abstract Mn2+ doped ZnO nanoparticles were synthesized by sol–gel auto combustion technique. The effects of Mn2+ doping on the 2+ 2+ Mn doped nanoparticles synthesized by sol–gel auto combustion technique. The effectswere of Mn doping on structural andZnO magnetic propertieswere of ZnO nanoparticles were investigated. Synthesized nanoparticles characterized by the XAbstract structural and magnetic of ZnOtransform nanoparticles werespectroscopy investigated.(FTIR). Synthesized nanoparticles werestructure characterized Xray diffraction techniqueproperties (XRD), Fourier infrared The hexagonal wurtzite with by single ray diffraction (XRD), Fourier were transform infrared spectroscopy The hexagonal structurebywith single phase of Mn2+technique doped ZnO nanoparticles confirmed by XRD analysis.(FTIR). The average crystallite wurtzite size determined Scherrer's Under the concept of "Industry 4.0", production processes will be pushed to be increasingly interconnected, phase of was Mn2+ doped ZnO nanoparticles by XRD analysis. The average crystallite sizeX-ray determined Scherrer's formula found in the range 14–17 nm.were It is confirmed observed that the lattice parameter, volume of unit cell, density,byand atomic information basedinonthea range real time necessarily, much more efficient. In this context, capacity optimization 2+ observed formula found 14–17basis nm.Mn Itand, is that the lattice parameter, volume of unit density, andof atomic packing was fraction increase with increasing content. FTIR analysis revealed a slight change incell, mainX-ray absorption band ZnO 2+ maximization, contributing also for organization’s profitability and value. goes beyond the traditional aim of capacity −1 FTIR analysis a slight in main absorption band of ZnO packing fraction range increase with increasing Mn content. in the frequency of 500-1000 cm . Magnetic characterization wasrevealed performed usingchange vibrating sample magnetometer (VSM) Indeed, lean management and cm continuous approaches suggest capacity optimization instead of . Magnetic characterization wasnanoparticles performed using vibrating sample magnetometer (VSM) in thewhich frequency range the of 500-1000 and, evidenced properties of−1pure ZnO improvement and Mn doped ZnO showed the diamagnetic and paramagnetic maximization. The study of capacity optimization and costing models is an important research topic that deserves and, which evidenced the properties of pure ZnO and Mn doped ZnO nanoparticles showed the diamagnetic and paramagnetic behaviour respectively. contributions from both the practical and theoretical perspectives. This paper presents and discusses a mathematical behaviour respectively. model on different costing models (ABC and TDABC). A generic model has been © 2017for Thecapacity Authors.management Published bybased Elsevier B.V. © The Authors. Published byby Elsevier B.V.B.V. © 2018 2017The Authors. Published Elsevier Peer-review under responsibility of the scientific committee of the 2nd International Conference on of Materials developed and it was used to analyze idle capacity and strategies towards theon maximization organization’s Peer-review under responsibility of the scientific committee ofto thedesign 2nd International Conference Materials Manufacturing and Peer-review under responsibility of the scientific committee of the 2nd International Conference on Materials Manufacturing and Design Engineering. value. The trade-off capacity maximization vs operational efficiency is highlighted and it is shown that capacity Design Engineering. b

Manufacturing and hide Design Engineering. optimization might operational inefficiency.

Keywords: XRD; ZnO; FTIR, VSM by Elsevier B.V. © 2017 The Authors. Published Keywords: XRD; ZnO; FTIR, VSM Peer-review under responsibility of the scientific committee of the Manufacturing Engineering Society International Conference 2017.

Keywords: Cost Models; ABC; TDABC; Capacity Management; Idle Capacity; Operational Efficiency

1. Introduction * Corresponding author. Tel.: +91-9822736542 ; fax: +91 - 240 - 2375275, 2376154 * The Corresponding author. Tel.: +91-9822736542 ; fax: information +91 - 240 - 2375275, 2376154 and their management of extreme importance E-mail address: [email protected] cost of idle capacity is a fundamental for companies E-mail address: [email protected]

in modern production systems. In general, it is defined as unused capacity or production potential and can be measured 2351-9789© 2017 The Authors. Published by Elsevier B.V. in several ways: tons of production, available hours of manufacturing, etc. The management of the idle capacity 2351-9789© 2017 The Authors. Published Elsevier B.V. Peer-review under responsibility of thebyscientific committee of the 2nd International Conference on Materials Manufacturing and * Paulo Afonso. Tel.: +351 253 510of 761; +351 253 604 741 of the 2nd International Conference on Materials Manufacturing and Peer-review under responsibility thefax: scientific committee Design Engineering. E-mail address: [email protected]

Design Engineering.

2351-9789 © 2017 The Authors. Published by Elsevier B.V. Peer-review under of the scientificbycommittee the Manufacturing Engineering Society International Conference 2017. 2351-9789 © 2018responsibility The Authors. Published Elsevier of B.V. Peer-review under responsibility of the scientific committee of the 2nd International Conference on Materials Manufacturing and Design Engineering. 10.1016/j.promfg.2018.02.025

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1. Introduction From last few decades, the scientist and researchers have been looking intensively at the use of nanomaterials because of their excellent physical [1] and chemical properties [2] compared to bulk materials. Nowadays, nanostructures material are being used in the manufacturing of sensors, solar panel display, anti-graffiti coatings for walls, transparent sunscreens, stain-repellent fabrics etc. ZnO is one of the important and attractive nanostructure materials due to their optical and magnetic properties. ZnO material can be used to fabricate optoelectronic device due their wide energy band gap (3.37 eV) and large exciton binding energy (60 meV) [3, 4]. The development of novel nanostructure material in the form of thin films, nanoparticles, nanowire, nanowalls etc, it is an essential part of research as well as technology. In order to develop new technology, it is important to understand fundamental properties of nanomaterials. Fundamental properties of nanomaterials depend on size of nanoparticles, colour of nanoparticles, doping concentrations, sintering temperature, synthesis temperature etc. The properties of ZnO nanoparticles can be controlled by introducing the dopant element [5]. Doping of transition metal ions in the ZnO has lead to the enhancement of the band gap, optical, electrical and magnetic properties [6-8]. The transition metal ions have several advantages as a dopant that makes easy to incorporate into ZnO crystal structures and induced the magnetic as well as optical properties [9, 10]. Recently, the transition metal ions like Co2+, Mn2+, Fe2+, Ni2+, etc substitution in ZnO has received special attention [11]. The role played by the substituent in modifying the physical properties of ZnO and the mechanism behind reduce the size of nanoparticles and enhanced magnetic response is not widely studied. Furthermore, many theoretical and experimental evidences suggested that ZnO doped with transition metals is a promising semiconductor material exhibiting ferromagnetism when doped with transition metal ions like Co, Ni [12]. The control of chemical composition, purity, morphology, and particle size is very important to obtain suitable metalions doped ZnO powders for their desired applications. A number of synthesis methods have been devoted to the fabrication of transition metal doped ZnO nanoparticles, such as auto combustion method [13], ball milling method [14], co-precipitation method [15], hydrothermal process [16], solid state reaction method [17]. Among these synthesis methods, sol gel auto combustion method was used for the synthesis of Mn doped ZnO nanoparticles [18]. Using sol gel auto combustion method, reagents can be mixed at molecular level, easily control agglomeration of nanoparticles and reaction can be carried at low temperature [19]. In order to fabricate spintronic and optoelectronic device at room temperature, it is necessary to understand magnetic and optical properties of nanomaterials. These properties can be changed with doping of transition metal ions such as Ni2+, Co2+, Fe3+, Mn2+, Zn2+ etc. Among the transition metal ions, manganese is considered as a potential candidate because of its variable oxidation state, large solubility limit in ZnO matrix. In the present work, the effect of manganese ions on the structural and magnetic properties of ZnO nanoparticles has been investigated and the obtained experimental results are presented. 2. Experimental details 2.1 Synthesis of Mn doped nanoparticles Nanocrystalline Zn1-xMnxO (x = 0.0, 0.06 and 0.12) samples were synthesized by a sol-gel auto-combustion technique. Analytical grade chemicals were used for synthesis of Mn doped ZnO nanoparticles. Zinc nitrate hexahydrate (Zn (NO3)2.6H2O, Sigma-Aldrich 99.999 %), manganese nitrate hexahydrate (Mn (NO3)2.6H2O, SigmaAldrich 98.0 %), and citric acid monohydrate (C6H8O7.H2O, Sigma-Aldrich 99 %), were used. Double distilled water (Merck & Co., Inc.) was used as a solvent. Citric acid was used as a fuel. The fuel ratio was taken according to stoichiometric proportion of metal nitrate to oxidizer ratio (1:1). In a typical synthesis of Zn 1‒xMnxO samples, the appropriate proportion of Zn (NO3)2.6H2O, Mn (NO3)2.6H2O and C6H8O7.H2O were completely dissolved in a minimum amount of double distilled water to get the aqueous solution. The aqueous solution was then stirred for about 1 h in order to mix the solution uniformly. The mixed solution was evaporated to dryness by heating at 120 C on a hot plate with continuous constant stirring and finally formed a very viscous gel. The viscous gel was ignited by increasing temperature up to 200  C and the loose and burnt powder of the samples was obtained. Finally, the burnt powder was sintered at 600  C for 6 h to obtain manganese substituted zinc oxide nanoparticles. The resulting

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powders of undoped and manganese doped ZnO powder were white in colour. All the samples were ground for a half an hour and used for further characterization. 2.2. Characterization techniques The crystalline nature and the phase identification of Mn doped ZnO nanoparticles were examined through X-ray powder diffraction analysis (XRD) technique using (Model: Xpert PRO MPD) with Cu-Kα radiations (λ = 1.5405 Å) operated at a voltage of 45 kV and current of 40 mA. Fourier transform infrared spectroscopy (FT-IR) spectra of all the samples were recorded in the range of 400 - 4000 cm-1. The field dependent magnetizations were measured by vibrating sample magnetometer (VSM) at room temperature. 3. Results and discussion 3.1 X-ray diffraction study (XRD) The X-ray diffraction patterns of all synthesized Zn1–xMnxO (0.0≤x≤0.12) nanoparticles are shown in Fig. 1 X-ray diffraction analysis revealed that all the diffraction peaks in the XRD pattern well match with the standard pattern of pure ZnO (JCPDS: 36- 1451). From the analysis of XRD pattern of undoped and Mn doped ZnO nanoparticles revealed the formation of hexagonal wurtzite structure.

Fig. 1 X-ray diffraction pattern of Zn1‒xMnxO (x = 0.00, 0.06 and 0.12) nanoparticles From the analysis of Fig. 1, it is found that the diffraction peak intensities decreases with an increase in Mn 2+ content in ZnO matrix, which indicates that the dopant Mn 2+ ions are substituted in the inner lattice of Zn 2+ ions. Average crystallite size of nanoparticles was calculated from the Debye-Scherrer’s equation [20].

D = (K ∗  )/(  ∗ cos  )

(1)

where, k = 0.90,  is the X-ray wavelength (1.540562 Å),  is the full width half maximum of the most intense peak,  is the Bragg’s angle position. The increase of the full width at half maxima of the diffraction peak reveals that the crystallite size decreases with increase in Mn 2+ content. The average crystallite size of pure and Mn doped ZnO nanoparticles were found to be in the range 17–14 nm. The reduction in the average crystallite size is mainly due to the distortion in the host (ZnO) lattice by foreign impurity introducing that decrease the nucleation and growth rate of ZnO nanoparticles [21]. The lattice parameters of the hexagonal wurtzite structure undoped and Mn 2+ doped ZnO nanoparticles were calculated from the using equation [20, 22].

Author name / Procedia Manufacturing 00 (2017) 000–000 Shankar D. Birajdar et al. / Procedia Manufacturing 20 (2018) 174–180

1/𝑑𝑑^2 = [4/3 ((ℎ)^2 + ℎ𝑘𝑘 + ( 𝑘𝑘)^2 )/𝑎𝑎^2 + 𝑙𝑙^2/𝑐𝑐^2 ) ]

177

(2)

The calculated lattice parameters ‘a’ and ‘c’ of undoped and Mn2+ doped ZnO nanoparticles are 3.2397, 3.2454 and 3.2489 for x = 0.0,0.06 and 0.12 mol respectively. The lattice parameters a and c are found to increase with increase in Mn content in ZnO nanoparticles because of higher ionic radius of Mn 2+ ions (0.83 Å) in comparison to the Zn 2+ ions ( 0.72 Å). A similar behaviour of lattice parameter has been reported Mn by Duan L B et al. [23]. The volume of the unit cell was calculated using the equation [21]. V = (√3/2) a^2 ∗ c

(3)

where, V is the volume of the hexagonal unit cell, a and c are lattice parameter. It was found that the volume of the unit cell increases with increase of Mn 2+ doping level, the obtained values of volume of unit cell present sample are 47.23, 47.44 and 47.59 for x = 0.0,0.06 and 0.12 mol respectively. The X-ray density was determined using the equation [24]. ρx = nM/(N A V)

(4)

APF = 2πa/(3√3c)

(5)

𝑙𝑙 = √(𝑎𝑎^2/3) + (1/2 − 𝑢𝑢)^2

(6)

where, n is the number of atoms per unit cell, M is the molecular weight, NA is the Avogadro’s number and V is the volume of the unit cell. The X-ray density and volume of unit cell increases with the increase in Mn 2+ content. It means that Mn2+ ions go to the Zn2+ site in ZnO structure[25]. The atomic packing fraction was calculated using the equation [22].

where, a and c are the lattice parameters. The obtained values of atomic packing factors (APF) are 1.9724, 1.9753 and 1.9774 for x =0.0, 0.06 and 0.12 respectively. It is found that values of atomic packing factor increase with increase in Mn content, it may be due to the decreases of voids in the samples. The variation of atomic packing factor, it suggests that homogeneous substitution of Mn2+ ions in the Zn2+ site of ZnO hexagonal wurtzite structure. The bond length of undoped and doped ZnO nanoparticles has been calculated using the following equation [21].

where, a and c are lattice constant, u is the positional parameter. The Zn-O bond length is obtained from lattice parameters ‘a’ and positional parameters ‘u’ in the wurtzite structure, which has been observed that ‘bond length (l) increases with the increase in Mn 2+ content, it may be due to the effect of replacement of Mn 2+ ions in ZnO. 3.2. Fourier transforms infrared spectroscopy (FTIR) Fourier transforms infrared absorption measurement technique was employed to confirm the formation of hexagonal wurtzite structure. FTIR measurements of all the samples were performed in the wave number range from 400 to 4,000 cm-1 using the KBr method at room temperature as shown in Fig. 2. From the analysis of FTIR spectra, it is found, the absorption peaks between 1536 cm-1 and 1515 cm-1 , which are corresponding to asymmetric and symmetric stretching of the carboxyl group (C=O) [26]. The broad absorption peak showed the presence of O-H stretching mode of H2O in the ZnO nanocrystals around 3403 cm -1 for pure ZnO, 3396 cm-1 ,3389 cm-1 for (x= 0.06, 0.12 ) respectively [27, 28]. The absorption peaks were observed between 2348 cm-1 and 2307 cm-1, which are because of the existence of O-C-O molecule in the atmosphere [29, 30].


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Fig.2 FTIR spectra of of Zn1‒xMnxO (x = 0.00, 0.06 and 0.12) nanoparticles The main absorption band of Zn-O stretching, vibration at 460 cm-1, 475 cm-1, 481 cm-1 for 0.00, 0.06 and 0.12 respectively [31-35]. There is a slight change in the band position observed due to the substitution of Mn2+ content. The band positions are slightly shifted towards higher frequency with increase in Mn 2+ substitution in ZnO matrix. From the FTIR study it is confirmed that Mn2+ ions are substituted into the ZnO matrix 3.3. Vibrating sample magnetometer measurement (VSM) The magnetic properties of Mn 2+ doped zinc oxide nanoparticles were carried out using vibrating sample magnetometer (VSM) technique. Fig. 3 (a-c) shows the field–dependent magnetization curve of Mn2+ doped ZnO nanoparticles at room temperature. From the analysis of the M-H curve of undoped (ZnO) sample, it shows the clear diamagnetic behaviour [36-39]. The perfect linear (M-H) curve nature of Mn 2+ doped ZnO sample, indicate the absence of ferromagnetic and exhibit paramagnetic nature at room temperature [40-42].

(a)

(b)

(c)

Fig.3 (a-c) M-H plots of Zn 1‒xMnxO (x = 0.00, 0.06 and 0.12) nanoparticles In order to understand transition from diamagnetic to paramagnetic state in Mn doped ZnO nanoparticles, it is necessary to know the oxidation state of Mn ions, according to X-ray diffraction pattern peak intensities decreases with an increase in Mn content in the host (ZnO) lattice, variation of lattice parameter a and c with increase in Mn content, all these variation indicates the dopant Mn 2+ ions are substituted in the inner lattice of Zn 2+ ions. Additionally, the substitution of Zn ion Zn 2+ (0.72 Å) by Mn2+ ions (0.83 Å) does not cause any significant change in the host (ZnO) lattice. Hence it is logical to assume that Mn2+ goes into the ZnO lattice in the same oxidation

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state as Zn (i.e., 2+) with a tetrahedral coordination. According to recent experimental results, Alaria et al. [43] reported that pure paramagnetic behaviour in Mn-doped ZnO synthesized by co-precipitation method was reported, where the absence of ferromagnetism was probably due to the lack of free carriers. A. Sivagamasundari et al., [44] have studied that paramagnetism has been observed due to non availability of free carriers. Shi T. et al. [45] reported that neutral dopant atom which do not produce free carrier from X-ray absorption near edge structure (XANES) studies. Hence, non availability of free carriers is responsible for the observed paramagnetism in the prepared samples. The absence of ferromagnetic properties and the presence of purely paramagnetic properties due to the incorporation of Mn2+, which supports no secondary phase detected in XRD pattern. 4. Conclusions Pure and Mn2+ doped ZnO nanoparticles were successfully synthesized by sol gel auto-combustion route. XRD results confirm the prepared samples are in the nano-scale regime having a hexagonal wurtzite structure with single phase. The FT-IR analysis confirmed the presence of Zn-O bond and substitution of Zn 2+ ions by Mn2+ ions in the crystal lattice structure. The detailed analysis of field dependent magnetic data of Mn doped ZnO nanoparticles, which revealed that the observed paramagnetic behavior at room temperature due to the absence of secondary phase and lack of free carrier concentration, which is supported by VSM and XRD. Acknowledgement The first author would like to thank to Department of Physics, Dr. B. A. Marathwada University, Aurangabad and Tata Institute of Fundamental Research (TIFR), Mumbai for providing laboratory VSM characterization facilities. References [1] S. Pearton, D. Norton, Y. Heo, L. Tien, M. Ivill, Y. Li, B. Kang, F. Ren, J. Kelly, A. Hebard, ZnO spintronics and nanowire devices, Journal of electronic materials, 35 (2006) 862-868. [2] A. Djurišić, A. Ng, X. Chen, ZnO nanostructures for optoelectronics: material properties and device applications, Progress in Quantum Electronics, 34 (2010) 191-259. [3] J. Tian, J. Wang, J. Dai, X. Wang, Y. Yin, N-doped TiO 2/ZnO composite powder and its photocatalytic performance for degradation of methyl orange, Surface and Coatings Technology, 204 (2009) 723-730. [4] A.P. Bhirud, S.D. Sathaye, R.P. Waichal, L.K. Nikam, B.B. Kale, An eco-friendly, highly stable and efficient nanostructured p-type N-doped ZnO photocatalyst for environmentally benign solar hydrogen production, Green Chemistry, 14 (2012) 2790-2798. [5] P. Yang, H. Yan, S. Mao, R. Russo, J. Johnson, R. Saykally, N. Morris, J. Pham, R. He, H.-J. Choi, Controlled growth of ZnO nanowires and their optical properties, Advanced Functional Materials, 12 (2002) 323. [6] J. Zhang, L. Sun, J. Yin, H. Su, C. Liao, C. Yan, Control of ZnO morphology via a simple solution route, Chemistry of Materials, 14 (2002) 4172-4177. [7] J. Xu, Q. Pan, Z. Tian, Grain size control and gas sensing properties of ZnO gas sensor, Sensors and Actuators B: Chemica l, 66 (2000) 277279. [8] B. Panigrahy, M. Aslam, D. Bahadur, Controlled optical and magnetic properties of ZnO nanorods by Ar ion irradiation, Applied Physics Letters, 98 (2011) 183109. [9] B. Pal, P. Giri, High temperature ferromagnetism and optical properties of Co doped ZnO nanoparticles, Journal of Applied Physics, 108 (2010) 084322. [10] I. Akyuz, S. Kose, F. Atay, V. Bilgin, The optical, structural and morphological properties of ultrasonically sprayed ZnO: Mn films, Semiconductor science and technology, 21 (2006) 1620. [11] F. Pan, C. Song, X. Liu, Y. Yang, F. Zeng, Ferromagnetism and possible application in spintronics of transition -metal-doped ZnO films, Materials Science and Engineering: R: Reports, 62 (2008) 1-35. [12] K. Sato, H. Katayama-Yoshida, First principles materials design for semiconductor spintronics, Semiconductor Science and Technology, 17 (2002) 367. [13] S. Ekambaram, Combustion synthesis and characterization of new class of ZnO-based ceramic pigments, Journal of alloys and compounds, 390 (2005) L4-L6. [14] S. Suwanboon, P. Amornpitoksuk, A. Sukolrat, N. Muensit, Optical and photocatalytic properties of La -doped ZnO nanoparticles prepared via precipitation and mechanical milling method, Ceramics International, 39 (2013) 2811-2819. [15] O. Jayakumar, H. Salunke, R. Kadam, M. Mohapatra, G. Yaswant, S. Kulshreshtha, Magnetism in Mn-doped ZnO nanoparticles prepared by a co-precipitation method, Nanotechnology, 17 (2006) 1278.

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