Politeknik Dergisi 2147-9429 Gazi University 10.2339/politeknik.647702 Engineering Mühendislik Band Gap Engineering of ZnO Nanocrystallites Prepared via Ball-Milling Band Gap Engineering of ZnO Nanocrystallites Prepared via Ball-Milling https://orcid.org/0000-0003-4852-2230 Şimşek Telem HACETTEPE UNIVERSITY Ceylan Abdullah HACETTEPE ÜNİVERSİTESİ Aşkın Gülçin Şefiye HACETTEPE ÜNİVERSİTESİ Özcan Şadan HACETTEPE ÜNİVERSİTESİ 03 01 2022 25 1 89 94 11 16 2019 09 30 2020 Copyright © 1998, Journal of Polytechnic 1998 Journal of Polytechnic

Zinc oxide (ZnO) nanostructures have become the foremost prevalent metal oxide materials for technological applications due to their tunable optical properties. However, a simple, cheap and green method is required for the mass production of these nanostructures. In the present investigation ball-milling technique was used to tune the band gap of ZnO nanocrystallites. Samples were synthesized using metallic Zn powder and distilled water via wet-milling followed by dry-milling. The crystallite size of the ZnO samples were determined in the range of 24.9 – 22.0 nm depending on the dry milling time. UV-vis absorbance measurements and Kubelka-Munk theory were used to calculate the band gap of the ZnO nanocrystallites. The energy band gap of the samples was successfully tuned in the range of 3.15 - 3.02 eV depending on the nanocrystallite size. This behavior was explained by the surface states and energy traps on the band edge, created by delocalization of molecular orbitals.

Zinc oxide (ZnO) nanostructures have become the foremost prevalent metal oxide materials for technological applications due to their tunable optical properties. However, a simple, cheap and green method is required for the mass production of these nanostructures. In the present investigation ball-milling technique was used to tune the band gap of ZnO nanocrystallites. Samples were synthesized using metallic Zn powder and distilled water via wet-milling followed by dry-milling. The crystallite size of the ZnO samples were determined in the range of 24.9 – 22.0 nm depending on the dry milling time. UV-vis absorbance measurements and Kubelka-Munk theory were used to calculate the band gap of the ZnO nanocrystallites. The energy band gap of the samples was successfully tuned in the range of 3.15 - 3.02 eV depending on the nanocrystallite size. This behavior was explained by the surface states and energy traps on the band edge, created by delocalization of molecular orbitals.

 Band gap engineering dry-milling zinc oxide wet-milling bang gap engineering dry-milling zinc oxide wet-milling [1] Rasmussen J.W., Martinez E., Louka P. and Wingett D.G., “Zinc oxide nanoparticles for selective destruction of tumor cells and potential for drug delivery applications”, Expert Opinion on Drug Delivery, 7: 1063–1077, (2010) [2] Xiong H.M., Xu Y., Ren Q.G. and Xia Y.Y., “Stable Aqueous ZnO@Polymer Core−Shell Nanoparticles with Tunable Photoluminescence and Their Application in Cell Imaging”, Journal of American Chemical Society, 18: 7522-3, (2008) [3] Pan Z.Y., Liang J., Zheng Z.Z, Wang H.H. and Xiong H.M., “The application of ZnO luminescent nanoparticles in labeling mice”, Contrast Media & Molecular Imaging, 6: 328–30, (2011) [4] Singh S.P., “Multifunctional magnetic quantum dots for cancer theranostics”, Journal of Biomedical Nanotechnology, 7: 95–7, (2011) [5] Hong H., Shi J., Yang Y., Zhang Y., Engle J.W., Nickles R.J., Wang X. And Cai W., “Cancer-Targeted Optical Imaging with Fluorescent Zinc Oxide Nanowires”, Nano Letters, 11: 3744–50, (2011) [6] Wang X., Summers C. J. and Wang Z.L., “Large-scale hexagonal-patterned growth of aligned ZnO nanorods for nano-optoelectronics and nanosensor arrays”, Nano Letters, 4: 423–426, (2004) [7] Huang M.H., Mao S., Feick H., Yan H., Wu Y., Kind H., Weber E., Russo R. and Yang P., “Room-Temperature Ultraviolet Nanowire Nanolasers”, Science, 292: 1897-1899, (2001) [8] Ko Y.H. and Yu J.S., “Urchin-aggregation inspired closely-packed hierarchical ZnO nanostructures for efficient light scattering”, Optics Express, 27: 25935-25943, (2011) [9] Wang X., Summers C.J. and Wang Z.L.,” Large-Scale Hexagonal-Patterned Growth of Aligned ZnO Nanorods for Nano-optoelectronics and Nanosensor Arrays”, Nano Letters, 4: 423-6, (2004) [10] Singh P. and Nanda A., “Enhanced sun protection of nano-sized metal oxide particles over conventional metal oxide particles: an in vitro comparative study”, International Journal of Cosmetic Science, 36: 273-83, (2014) [11] Iwasaki T., Satoh M., Masuda T. And Fujita T., “Powder design for UV-attenuating agent with high transparency for visible light”, Journal of Materials Science, 35: 4025-4029, (2000) [12] Zhou H., Li J., Bao S., Li J., Liu X. and Jin P., “Use of ZnO as antireflective, protective, antibacterial, and biocompatible multifunction nanolayer of thermochromic VO2 nanofilm for intelligent windows”, Applied Surface Science, 363: 15, 532–542, (2016) [13] Lee Y.J., Ruby D.S., Peters D.W., McKenzie B.B. and Hsu J.W.P., “ZnO nanostructures as efficient antireflection layers in solar cells”, Nano Letters, 8: 1501–1505, (2008) [14] Xu S., Adiga N., Ba S., Dasgupta T., Wu C.F.J. and Wang Z.L., “Optimizing and Improving the Growth Quality of ZnO Nanowire Arrays Guided by Statistical Design of Experiments”, ACS Nano, 3: 1803-1812, (2009) [15] Xue X., Zang W., Deng P., Wang Q., Xing L., Zhang Y. and Wang, Z.L., “Piezo-potential enhanced photocatalytic degradation of organic dye using ZnO nanowires”, Nano Energy, 13: 414–422, (2015) [16] Mishra Y.K., Modi G., Cretu V., Postica V., Lupan O., Reimer T., Paulowicz I., Hrkac V., Benecke W., Kienle L. and Adelung R., “Direct Growth of Freestanding ZnO Tetrapod Networks for Multifunctional Applications in Photocatalysis, UV Photodetection, and Gas Sensing”, ACS Applied Materials & Interfaces, 7: 14303–14316, (2015) [17] Hsua C., Chen K., Tsaic T. and Hsueh T., “Fabrication of gas sensor based on p-type ZnO nanoparticles and n-type ZnO nanowires”, Sensors and Actuators B: Chemical, 182: 190–196, (2013) [18] Kazemi A.S., Afzalzadeh R. and Abadyan M., “ZnO Nanoparticles as Ethanol Gas Sensors and the Effective Parameters on Their Performance”, Journal of Materials Science and Technology, 5: 393–400, (2013) [19] Wang R.C. and Tsai C.C., “Efficient synthesis of ZnO nanoparticles, nanowalls, and nanowires by thermal decomposition of zinc acetate at a low temperature”, Applied Physics A, 94: 241-245, (2009) [20] Wang C., Shen E., Wang E., Gao L., Kang Z., Tian C., Lan Y. and Zhang C., “Controlable synthesis of ZnO nanoparticles via a surfactant assisted alcohol thermal process at low temperature”, Current Applied Physics, 6: 499–502, (2006) [21] Raied K.J., Mohammed A.H. and Kadhim A.A., “Optical properties of nanostructured ZnO prepared by pulsed laser deposition technique”, Materials Letters, 132: 31–33, (2014) [22] Zhaoa C. Huang Y. and Abiade J.T., “Ferromagnetic ZnO nanoparticles prepared by pulsed laser deposition in liquid”, Materials Letters, 85: 164–167, (2012) [23] Gao P.X. and Wang Z.L., “Nanopropeller arrays of zinc oxide”, Applied Physics Letters, 15: 2883-2887, (2004) [24] Khorsand Z., Abid A., Majid W.H., Wang H.Z., Yousefi R., Golsheikh M. and Ren Z.F., “Sonochemical synthesis of hierarchical ZnO nanostructures”, Ultrasonic Sonochemistry, 20: 395–400, (2013) [25] Kandjani A.E., Tabriz M.F. and Pourabbas B., “Sonochemical synthesis of ZnO nanoparticles: The effect of temperature and sonication power”, Materials Research Bulletin, 43: 645–654 (2008) [26] Khanna K., Kate K., Dhanabalan K., Banerjee S., Reji N., Shinde S.D. and Jain G. H., “Sono-chemical synthesis of ZnO nano-particles and their application in hydrogen sulphide gas sensing”, Journal of Nanoscience and Nanotechnology, 12: 2791-6, (2012) [27] Xu C., De S., Balu A.M., Ojeda M. and Luque R., “Mechanochemical synthesis of advanced nanomaterials for catalytic applications”, Chemical Communications, 51: 6698–6713, (2015) [28] Yadav T.P., Yadav R.M. and Singh D.P., “Mechanical Milling: a Top Down Approach for the Synthesis of Nanomaterials and Nanocomposites”, Nanoscience and Nanotechnology, 3: 22-48, (2012) [29] Glushenkov A.M, Zhang H.Z. and Chen Y., “Reactive Ball Milling to Produce Nanocrystalline ZnO”, Materials Letters, 62: 4047–4049, (2008) [30] Ghose S., Sarkar A., Chattopadhyay S., Chakrabarti M., Das D., Rakshit T., Ray S.K. and Jana D., “Surface defects induced ferromagnetism in mechanically milled nanocrystalline ZnO”, Journal of Applied Physics, 114: 073516, (2013) [31] Phan D., Zhang Y.D., Yang D.S., Nghia N.X., Thanh T.D. and Yu S.C., “Defect-induced ferromagnetism in ZnO nanoparticles prepared by mechanical milling”, Applied Physics Letters, 102: 072408-5, (2013) [32] Damonte L.C., Zélis L.A., Soucase B.M. and Fenollos M.A., “Nanoparticles of ZnO obtained by mechanical milling”, Powder Technology, 148: 15–19 (2004) [33] Salah N., Habib S.S., Khan, Z.H., Memic A., Azam A., Alarfaj E., Zahed N. and Al-Hamedi S., “High-energy ball milling technique for ZnO nanoparticles as antibacterial material”, International Journal of Nanomedicine, 6: 863–869, (2011) [34] Anand K., Varghese S. and Kurian, T., “Preparation of ultra-fine dispersions of zinc oxide by simple ball-milling: Optimization of process parameters”, Powder Technology, 271: 187–192, (2015) [35] Balamurugan S., Joy J., Godwin M.A., Selvamani S. and Raja T.S.G., “ZnO nanoparticles obtained by ball milling technique: Structural, micro-structure, optical and photo-catalytic properties”, AIP Conference Proceedings, 1731: 050121, (2016) [36] Giri P.K., Bhattacharyya S. and Singh D.K., “Correlation between microstructure and optical properties of ZnO nanoparticles synthesized by ball milling”, Journal of Applied Physics, 102: 093515–8, (2007) [37] Balaland S., Babitha K.B., Maria M.J., Mohamed A.A.P. and Ananthakumar S., “Aqueous Mechanical Oxidation of Zn Dust: An Inventive Technique for Bulk Production of ZnO Nanorods”, ACS Sustainable Chemistry & Engineering, 6: 143–154, (2018) [38] Özcan Ş.; Can M.M. and Ceylan A., “Single step synthesis of nanocrystalline ZnO via wet-milling”, Materials Letters, 64: 2447–2449, (2010) [39] Lutterotti L.; Matthies S.and Wenk H.R., “"MAUD (Material Analysis Using Diffraction): a user friendly {Java} program for {Rietveld} Texture Analysis and more”, Proceedings of the 12th International Conference on Textures of Materials (ICOTOM-12), 1: 1599, (1999) [40] Arunachalam V. and Raman O.V., “Powder metallurgy: recent advances”, Aspect Publications Ltd, (1990) [41] Upadhyaya A. and Upadhyaya G.S., “Powder Metallurgy: Science, Technology and Materials”, University Press, (2011) [42] Kortum G.F.A., “Reflectance Spectroscopy: Principles, Methods, Applications”, Springer, New York, (1969) [43] Brus L.E., “Electron–electron and electron‐hole interactions in small semiconductor crystallites: The size dependence of the lowest excited electronic state”, The Journal of Chemical Physics, 80: 4403 (1984) [44] Lin H., Huang C.P., Li W., Ni C., Shah S.I. and Tseng Y.H., “Size dependency of nanocrystalline TiO2 on its optical property and photocatalytic reactivity exemplified by 2-chlorophenol”, Applied Catalysis B: Environmental, 68: 1–11, (2006) [45] L. Bras, “Electronic wave functions in semiconductor clusters: experiment and theory”, The Journal of Physical Chemistry, 90: 2555-2560, (1986)