Crystallite Size Determination of Thermally Deposited Gold

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Procedia Manufacturing 30 (2019) 173–179 Procedia Manufacturing 00 (2017) 000–000 14th Global Congress on Manufacturing and Management (GCMM www.elsevier.com/locate/procedia-2018) Crystallite14th Global size Congress determination on Manufacturing of andthermally Management deposited (GCMM-2018) Gold Crystallite size determinationNanoparticles of thermally deposited Gold ManufacturingOlasupo Daniel Engineering Ogundare Societyab, , Ojo InternNanoparticles Jeremiahational Akinribide Conference ac *2017,, Adelana MESIC Rasak 2017, Adetunji 28-30 Juneb, Mosobalaje Oyebanji2017, Vigo Adeoye (Pontevedra),b, Peter Spain Apata Olubambic ab, ac b Olasupoa Daniel Ogundare , Ojo Jeremiah Akinribide *, Adelana Rasak Adetunji , Research and Developent Department, Engineering Materialsb Development Institute,611,Ondo road Akure,c Nigeria Costing modelsbMaterialMosobalaje forScience capacity and OyebanjiEngineering Department,optimiza Adeoye Obafemi, tionPeter Awolowo Apatain University, Industry Olubambi Ile-Ife, Nigeria. 4.0: Trade-off cCentre for Nanoengineering and Tribocorossion, University of Johannesburg, Johannesburg 2028, South Africa aResearchbetween andDepartment Developent used of Department, metallurgy, capacity EngineeringUniversity of Materials Johannesburg,and Developmentoperational Johannesburg, Institute,611,Ondo 2028, efficiency South road Africa Akure, Nigeria bMaterial Science and Engineering Department, Obafemi Awolowo University, Ile-Ife, Nigeria. cCentre for Nanoengineering and Tribocorossion, University of Johannesburg, Johannesburg 2028, South Africa DepartmentA. Santana of metallurgy,a, P. University Afonso of Johannesburg,a,*, A. Zanin Johannesburg,b, R. Wernke 2028, Southb Africa Abstract a University of Minho, 4800-058 Guimarães, Portugal b This paper has x-rayed an approach to investigateUnochapecó, the 89809-000 crystallite Chapecó, size of SC, thermally Brazil deposited gold nanoparticles on a glass Abstract substrate. The mined and beneficiated gold sample was deposited on glass slide in Nano-38 thermal depositor after the substrate has been technically prepared. The crystallite size and profile fitting of the nanoparticles were determined by X-ray This paper has x-rayed an approach to investigate the crystallite size of thermally deposited gold nanoparticles on a glass Diffractometer (XRD). The result showed that the average crystallite size of Au nanoparticles thermally deposited on glass slide Abstractsubstrate. The mined and beneficiated gold sample was deposited on glass slide in Nano-38 thermal depositor after the substrate was 14.4 ± 6.7 nm with lattice constants: a, b, c; 4.0789, 4.0789, and 4.0789 (Å) respectively. The TEM images have confirmed has been technically prepared. The crystallite size and profile fitting of the nanoparticles were determined by X-ray that high quality spherical Au NPs that were between 18 nm – 24 nm were successfully synthesized. The XRD has shown that the Diffractometer (XRD). The result showed that the average crystallite size of Au nanoparticles thermally deposited on glass slide Undermaterial the of theconcept gold nanoparticlesof "Industry is4.0", gold productionand crystalline proce in ssesstructure. will Narrowbe pushed size todistribution be increasingly and small interconnected, monosize gold was 14.4 ± 6.7 nm with lattice constants: a, b, c; 4.0789, 4.0789, and 4.0789 (Å) respectively. The TEM images have confirmed informationnanoparticles basedproduced on maya real proffer time advantages basis and, for necessarily, self-assembled much monolayer more efficient. formation In and this enhanced context, surface capacity area. optimization that high quality spherical Au NPs that were between 18 nm – 24 nm were successfully synthesized. The XRD has shown that the goesmaterial beyond of the the gold traditional nanoparticles aim of is capacity gold and maximization, crystalline in contributingstructure. Narrow also for size organization’s distribution and profitability small monosize and value. gold Indeed,nanoparticles lean produced management may proffer and advantagescontinuous for improvement self-assembled monolayerapproaches formation suggest and capacity enhanced optimization surface area. instead of maximization. The study of capacity optimization and costing models is an important research topic that deserves contributions from both the practical and theoretical perspectives. This paper presents and discusses a mathematical © 2018 The Authors. Published by Elsevier Ltd. model © 2019 for The capacity Authors. managementPublished by Elsevier based onLtd. different costing models (ABC and TDABC). A generic model has been This is an open access article under the CC BYBY-NC-ND-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/https://creativecommons.org/licenses/by-nc-nd/4.0/) ) developedSelection and and peer it was-review used under to analyze responsibility idle capacity of the andscientific to design committee strategies of the towards 14th Global the maximization Congress on Manufacturingof organization’s and ©Selection 2018 The and Authors. peer-review Published under by responsibility Elsevier Ltd. of the scientific committee of the 14th Global Congress on Manufacturing and value.Management The trade-off (GCMM- 2018).capacity maximization vs operational efficiency is highlighted and it is shown that capacity ThisManagement is an open (GCMM-2018). access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) optimizationSelection and mightpeer-review hide operationalunder responsibility inefficiency. of the scientific committee of the 14th Global Congress on Manufacturing and Keywords: crystallite size, thermal deposition, gold nanoparticles, XRD ©Management 2017 The Authors. (GCMM Published-2018). by Elsevier B.V. Peer-review under responsibility of the scientific committee of the Manufacturing Engineering Society International Conference 2017. Keywords: crystallite size, thermal deposition, gold nanoparticles, XRD Keywords: Cost Models; ABC; TDABC; Capacity Management; Idle Capacity; Operational Efficiency

* Corresponding author. Cell.: +27 73 5042962 E-mail address: [email protected] 1. Introduction * Corresponding author. Cell.: +27 73 5042962 2351-9789 © 2018 The Authors. Published by Elsevier Ltd. E-mail address: [email protected] ThisThe is an cost open of access idle articlcapacitye under is the a fundamentalCC BY-NC-ND information license (https://creativecommons.org/licenses/by for companies and their management-nc-nd/4.0/) of extreme importance inSelection modern and production peer-review undersystems. responsibility In general, of the it scientific is defined committee as unused of the capacity 14th Global or Congress production on Manufacturing potential and and can Management be measured in(GCMM2351 several-9789-2018) © ways: 2018. The tons Authors. of production, Published by Elsevieravailable Ltd .hours of manufacturing, etc. The management of the idle capacity This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) Selection* Paulo Afonso.and peer Tel.:-review +351 under 253 responsibility 510 761; fax: of+351 the 253scientific 604 741 committee of the 14th Global Congress on Manufacturing and Management (GCMME-mail-2018) address:. [email protected]

2351-97892351-9789 ©© 2017 2019 The The Authors. Authors. Published Published by Elsevier by Elsevier B.V. Ltd. Peer-reviewThis is an openunder access responsibility article ofunder the sciethentific CC BY-NC-NDcommittee of licensethe Manufacturing (https://creativecommons.org/licenses/by-nc-nd/4.0/ Engineering Society International Conference 2017.) Selection and peer-review under responsibility of the scientific committee of the 14th Global Congress on Manufacturing and Management (GCMM-2018). 10.1016/j.promfg.2019.02.025

10.1016/j.promfg.2019.02.025 2351-9789 174 Olasupo Daniel Ogundare et al. / Procedia Manufacturing 30 (2019) 173–179 Ogundare, et al. / Procedia Manufacturing 00 (2018) 000–000 2

1.0 Introduction

In the current decade, much attention has been given to the synthesis of metal nanoparticles. This demanding interest has motivated by unique properties displayed by nanoparticles in catalysis, medicine, optics and materials science [1-3]. Alloying metal nanoparticles have portrayed promising attempt to enhance the antibacterial and optical performance in the field of nanotechnology [4-8]. This could be a channel to produce multi-functionalized nanoparticles [9]. Pure silver and gold nanoparticles as well as AgAu nanoalloys in the size of 4 nm have been successfully analyzed using pulsed laser ablation [10].

In the past few years, functionalizing nanoparticles has been a major area of research that have been generating ripples due to its interdisciplinary nature and diverse functionalities [11– 17]. Au NPs loaded carbon nanotubes have been recently prepared by mixed acids treatment process with a view to determining its electrocatalytic properties [18]. Also, the nanoparticles of Au (Au NPs) bearing starch polymer have been prepared and characterized. The catalytic property of starch-borne Au NPs alloyed with phenylboronic acid in water as well as other several parameters has been studied [19].

The aim of this work was to deepen our understanding of the crystal size in thermally deposited gold nanoparticles with a view to ascertaining its response to optical properties. Here, we have reported the average crystallite size and lattice constant of Au nanoparticles thermally deposited on glass slide.

2.0 Experimental section

2.1 Material and preparation process

The gold sample used in this work was mined, beneficiated and processed from Itagunmodi deposit following standard procedure as outlined [20]. Pure Au solid target, washed with ethanol and de-ionized water, was immersed in 5 ml de-ionized water ﬁlled in quartz cuvette in order to remove any impurity. Glass substrate with the dimension 25mm x 12mm2 was used for the experiment. Vacuum evaporation was performed at room deposition temperature, total pressure of about 2x10-5 Pa, molybdenum container with source current more than 5Amp. The gold deposition was accomplished at room temperature using the gold target. The thickness of the deposited Au was determined from profilometer to be 5nm. The procedure was repeated thrice in order to minimize error, which could occur from using a single sample.

The substrate was approximately 25mm x 12mm wide glass slide piece with a shiny deposition of Au nanoparticles on one side. The sample was mounted to an aluminium stub with double sided tape and the stub was mounted on an x-y-z goniometer stage.

Plate 1 has shown low magnification image from the gold nanoparticles deposited on glass slide with the analysis area located at the intersection of the crosshairs on the image. Data was acquired on a Bruker GADDS microdiffractometer equipped with a Copper x-ray tube, incident-beam monochromator, 500micron pinhole collimator, laser alignment system and 2D detector. Unlike traditional point detectors, the 2D detector accepts diffraction from crystallites oriented in a wide variety of tilt angles with respect to the incident x-ray beam. This resulted in reasonable diffraction intensity even though the spot size analyzed was very small. To ensure that the sample height was correct, the GADDS employed a laser and camera system oriented so that the sample was in the correct position when the laser beam was in the center of the camera system.

Plate 2 has shown the image from the alignment camera for the sample. On the photo, the laser spot located at the crosshairs was observable but weak due to the reflective nature of the sample.

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1.0 Introduction

[18]. Also, the nanoparticles of Au (Au NPs) bearing starch polymer have been prepared and characterized. The catalytic property of starch-borne Au NPs alloyed with phenylboronic acid in water as well as other several Figure 1: Low magnification photo of Figure 2: High magnification alignment parameters has been studied [19]. Au nanoparticles thermally deposited on glass slide image of Au nanoparticles thermally deposited on glass slide

The aim of this work was to deepen our understanding of the crystal size in thermally deposited gold nanoparticles 3.0 Results and Discussion with a view to ascertaining its response to optical properties. Here, we have reported the average crystallite size and lattice constant of Au nanoparticles thermally deposited on glass slide.

2.0 Experimental section

2.1 Material and preparation process

Plate 1 has shown low magnification image from the gold nanoparticles deposited on glass slide with the analysis Figure 3: SEM images of the morphologies of the gold ore (a) (x100), c (x1000) and the extracted gold grains (b) (x100), (d) (x1000) [20] area located at the intersection of the crosshairs on the image. Data was acquired on a Bruker GADDS The SEM image (Figs. 3a and c) has illustrated that the surface structure of the particles of Au ore from Itagunmodi microdiffractometer equipped with a Copper x-ray tube, incident-beam monochromator, 500micron pinhole deposit are in trihedron shapes. The SEM (in Figs. 3b and d) image has confirmed that the morphology of the collimator, laser alignment system and 2D detector. Unlike traditional point detectors, the 2D detector accepts particles of Au mined was in tetrahedron and hexahedron shapes. diffraction from crystallites oriented in a wide variety of tilt angles with respect to the incident x-ray beam. This resulted in reasonable diffraction intensity even though the spot size analyzed was very small. To ensure that the The TEM images obtained from the Au NPs synthesis were shown in Fig. 4. The TEM images has elucidated that sample height was correct, the GADDS employed a laser and camera system oriented so that the sample was in the the gold colloids were in monodispersional state, this may not be unconnected to the negatively charged layer of correct position when the laser beam was in the center of the camera system. citrate ions which repel from each other. This monodispersity could be attributed to the probe preparation and

generation of color signal in chromatographic strip assay. Moreover, the TEM images have stipulated that most of Plate 2 has shown the image from the alignment camera for the sample. On the photo, the laser spot located at the the Au nanospheres were round or spherical in shape. The size range of the NPs could be noted to be between 21-29 crosshairs was observable but weak due to the reflective nature of the sample. nm. The average size of Au NPs has been evaluated by measuring the diameter of three particles on TEM images.

The average diameter of colloidal gold was in the range of 24.2 nm with few particles of higher size distribution.

Also, it could be noticed that the Au NPs are the dark spherical shaped dots with smooth surface morphology.

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Figure 4: TEM image of synthesized Au NPs

Figure 1 has shown the XRD scan data from the sample along with the selected background and the reference markers from the International Centre Diffraction Data / Inorganic Crystal Structure Database (ICDD/ICSD) for Au. The irregular background was due to amorphous scattering from the underlying glass slide. The positions of the reference markers have been indicated where in 2Θ an expected diffraction peak would occur and the height of the markers was related to the expected height of an experimental peak if the sample were fine grained and randomly oriented. 2Θ represented the Bragg’s angle between the incident and reflection x-ray beams. In XRD, you have crystallites in all orientations. Only those crystallites whose Bragg planes are at angle of Θ with respect to the incident angle will diffract at an angle of 2Θ with respect to the incident beam. Note that the Au (111) peak is much more intense than the other Au peaks which is reflected in profile fit results for Au nanoparticles, Thermal deposited in Fig 6 . This indicates that there is some moderate texture (i.e. preferred orientation) of the Au on the glass slide.

The broadening of an observed diffraction peak can be characterized in a simplistic way by its FWHM (Full Width at Half Maximum) value at a particular 2 angle as 38o, 43o, 65o, 78o and 82o respectively. Because the apparent FWHM of a peak is a mathematical combination (convolution) of the specimen broadening FW(S) and the instrumental broadening FW (I), instrumental broadening is subtracted from that of the observed diffraction peak. If the crystallites (crystalline domains) in the specimen are free of lattice strain, their average size can be estimated from the specimen broadening FW(S) of any single peak in the observed pattern according to the Scherrer formula:

Crystallite Size = K * λ / (FW(S) * Cos ()),[1] where  is the peak position and K is the dimensionless shape factor of the average crystallite, λ is the x-ray wavelength, FW(S) is the line broadening at half the maximum intensity (FWHM),  is the Bragg angle.

Profile fitting is required to determine the peak positions and widths used for calculating the average crystallite size. Figure 2 shows the profile fitting results for the Au nanoparticles thermally deposited on glass. The fitting details are shown in the table below the profile fit figure. The XS column shows the crystallite size in Angstroms for each peak based on the Scherer equation. The average crystallite size is shown in Table 1 for the Au peaks in the sample. Also shown in Table 1 is the Au structure (FCC) and lattice constants from the ICDD/ICSD data file. The ICDD/ICSD reference and peak data are shown in the Table 2.

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Table1. The average crystallite size Average Crystallite size Sample ID Phase (nm)

Gold Au Cubic, S.G: Fm-3m (225) Au nanoparticles Lattice Constants: thermally a, b, c; 4.0789, 4.0789, 4.0789 (Å) 14.4 ± 6.7 nm deposited on glass α, β, γ ;<90.00°, 90.00°, 90.00°> slide Phase Info [01-075-6560]

Figure 4: TEM image of synthesized Au NPs

Table 2: ICDD/ICSD reference and peak data Figure 1 has shown the XRD scan data from the sample along with the selected background and the reference markers from the International Centre Diffraction Data / Inorganic Crystal Structure Database (ICDD/ICSD) for Au. Crystallite 2Θ Angle d(Å) I%(f) ( h k l) θ(°) 1/(2d) 2π/d The irregular background was due to amorphous scattering from the underlying glass slide. The positions of the size # reference markers have been indicated where in 2Θ an expected diffraction peak would occur and the height of the markers was related to the expected height of an experimental peak if the sample were fine grained and randomly oriented. 2Θ represented the Bragg’s angle between the incident and reflection x-ray beams. In XRD, you have 1 38.185 2.3550 100.0 ( 1 1 1) 19.092 0.2123 2.6680 crystallites in all orientations. Only those crystallites whose Bragg planes are at angle of Θ with respect to the 2 44.382 2.0395 47.1 ( 2 0 0) 22.191 0.2452 3.0808 incident angle will diffract at an angle of 2Θ with respect to the incident beam. Note that the Au (111) peak is much more intense than the other Au peaks which is reflected in profile fit results for Au nanoparticles, Thermal deposited 3 64.571 1.4421 25.0 ( 2 2 0) 32.286 0.3467 4.3569 in Fig 6 . This indicates that there is some moderate texture (i.e. preferred orientation) of the Au on the glass slide. 4 77.560 1.2299 25.4 ( 3 1 1) 38.780 0.4066 5.1089 5 81.716 1.1775 7.0 ( 2 2 2) 40.858 0.4246 5.3361 The broadening of an observed diffraction peak can be characterized in a simplistic way by its FWHM (Full Width at Half Maximum) value at a particular 2 angle as 38o, 43o, 65o, 78o and 82o respectively. Because the apparent 6 98.119 1.0197 3.0 ( 4 0 0) 49.060 0.4903 6.1616 FWHM of a peak is a mathematical combination (convolution) of the specimen broadening FW(S) and the 7 110.806 0.9358 9.2 ( 3 3 1) 55.403 0.5343 6.7144 instrumental broadening FW (I), instrumental broadening is subtracted from that of the observed diffraction peak. If the crystallites (crystalline domains) in the specimen are free of lattice strain, their average size can be estimated 8 115.247 0.9121 8.7 ( 4 2 0) 57.624 0.5482 6.8889 from the specimen broadening FW(S) of any single peak in the observed pattern according to the Scherrer formula: 9 135.384 0.8326 7.4 ( 4 2 2) 67.692 0.6005 7.5464

Figure 5: Phase identification and (hkl)’s of Au nanoparticles thermally deposited on glass slide.

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Figure 6: Profile fit results for Au nanoparticles, Thermal deposited

Angle(°) d(Å) Height Area(α1) Area(α1)% FWHM(°) XS(Å) ( h k l) 1 38.265 2.3502 1974.8 1421.6 100.0 0.487 253 ( 1 1 1) 2 44.371 2.0400 218.7 375.9 26.4 1.114 84 ( 2 0 0) 3 64.688 1.4398 106.7 133.4 9.4 0.864 120 ( 2 2 0) 4 77.624 1.2290 95.3 134.5 9.5 1.035 106 ( 3 1 1) 5 81.799 1.1765 80.7 82.6 5.8 0.755 157 ( 2 2 2)

R=3.78% (related to goodness of fit; lower R implies better fit)

Conclusions The TEM images have confirmed that high quality spherical Au NPs that were between 18 nm – 24 nm were successfully synthesized. The XRD has shown that the material of the gold nanoparticles is gold and crystalline in structure. Narrow size distribution and small monosize thermally deposited gold nanoparticles produced may proffer advantages for self-assembled monolayer formation and enhanced surface area. These findings imply that the atomic scale interface structure plays an important role when continuous ultrathin films are being considered.

Competing interests

All authors have pronounced that no contending intrigues exist.

Acknowledgements

The authors are appreciative to Engineering Materials Development Institute (EMDI) Akure Nigeria for the bench Work, National Agency for Science and Engineering Infrastructure (NASENI) Abuja Nigeria and International Foundation for Science (IFS) Stockholm, Sweden (No F/5085-1) for the financing.

Olasupo Daniel Ogundare et al. / Procedia Manufacturing 30 (2019) 173–179 179 Ogundare, et al. / Procedia Manufacturing 00 (2018) 000–000 7 Ogundare, et al. / Procedia Manufacturing 00 (2018) 000–000 6 References [1] A. Patterson, "The Scherrer formula for X-ray particle size determination," Physical review, vol. 56, p. 978, 1939. [2] J.-Q. Huo, L.-Y. Ma, Z. Zhang, Z.-J. Fan, J.-L. Zhang, T. V. Beryozkina, et al., "Synthesis and biological activity of novel N-(3-furan- 2-yl-1-phenyl-1H-pyrazol-5-yl) amides derivatives," Chinese Chemical Letters, vol. 27, pp. 1547-1550, 2016. [3] R. Ferrando, J. Jellinek, and R. L. Johnston, "Nanoalloys: from theory to applications of alloy clusters and nanoparticles," Chemical reviews, vol. 108, pp. 845-910, 2008. [4] C. Rehbock, J. Jakobi, L. Gamrad, S. Van der Meer, D. Tiedemann, U. 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Chairam, "Gold nanoparticles stabilized by starch polymer and their use as catalyst in homocoupling of phenylboronic acid," Journal of King Saud University-Science, vol. 29, pp. 547-552, 2017. Conclusions [20] O. D. Ogundare, M. O. Adeoye, A. R. Adetunji, and O. O. Adewoye, "Beneficiation and Characterization of Gold from Itagunmodi Gold Ore by Cyanidation," Journal of Minerals and Materials Characterization and Engineering, vol. 2, p. 300, 2014. The TEM images have confirmed that high quality spherical Au NPs that were between 18 nm – 24 nm were successfully synthesized. The XRD has shown that the material of the gold nanoparticles is gold and crystalline in structure. Narrow size distribution and small monosize thermally deposited gold nanoparticles produced may proffer advantages for self-assembled monolayer formation and enhanced surface area. These findings imply that the atomic scale interface structure plays an important role when continuous ultrathin films are being considered.

Competing interests

All authors have pronounced that no contending intrigues exist.

Acknowledgements