[1] [1] J. G. Kim, D. L. Pugmire, D. Battaglia, and M. A. Langell, “Analysis of the NiCo2O4 spinel surface with Auger and X-ray photoelectron spectroscopy,” Applied Surface Science, 2000, 165(1): 70–84.

[2] [2] F. Iacomi, G. Calin, C. Scarlat, M. Irimia, C. Doroftei, M. Dobromir, et al., “Functional properties of nickel cobalt oxide thin films,” Thin Solid Films, 2011, 520(1): 651–655.

[3] [3] S. K. Chang, Z. Zainal, K. B. Tan, and N. A. Yusof, “Surface morphology and crystallinity of metal oxides in nickel-cobalt binary system,” Sains Malaysiana, 2012, 41(4): 465–470.

[4] [4] O. A. Hamadi, “Characteristics of CdO-Si heterostructure produced by plasma-induced bonding technique,” Proceedings of the Institution of Mechanical Engineers Part L: Journal of Materials Design & Applications, 2008, 222(1): 65.71.

[5] [5] O. A. Hamadi, “Effect of annealing on the electrical characteristics of CdO-Si heterostructure produced by plasma-induced bonding technique,” Iraqi Journal of Applied Physics, 2008, 4(3): 34.37.

[6] [6] R. Ding, L. Qai, and H. Y. Wang, “Scalable electrodeposition of cost-effective microsized NiCo2O4 electrode materials for practical applications in electrochemical capacitors,” ECS Electrochem Letters, 2012, 1(3): A43–A46.

[7] [7] M. Hussain, Z. H. Ibupoto, M. A. Abbasi, X. J. Liu, O. Nur, and M. Willander, “Synthesis of three dimensional nickel cobalt oxide nanoneedles on nickel foam, their characterization and glucose sensing application,” Sensors, 2014, 14(3): 5415–5425.

[8] [8] M. Y. Ho, P. S. Khiew, D. Isa, T. K. Tan, W. S. Chiu, and C. H. Chia, “A review of metal oxide composite electrode materials for electrochemical capacitors,” Nano, 2014, 9(6): 1430002-1–1430002-25.

[9] [9] O. A. Hammadi, “Photovoltaic properties of thermally-grown selenium-doped silicon photodiodes for infrared detection applications,” Photonic Sensors, 2015, 5(2): 152.158.

[10] [10] O. A. Hammadi and N. E. Naji, “Electrical and spectral characterization of CdS/Si heterojunction prepared by plasma-induced bonding,” Optical and Quantum Electronics, 2016, 48(8): 1.7.

[11] [11] S. U. Offiah, A. C. Nwanya, S. C. Ezugwu, B. T. Sone, R. U. Osuji, M. Maaza, et al., “Chemical bath synthesis and physico-chemical characterizations of NiO-CoO composite thin films for supercapacitor applications,” International Journal of Electrochemical Science, 2014, 9(10): 5837–5848.

[12] [12] W. W. Liu, C. Lu, K. Liang, and B. Tay, “A three dimensional vertically aligned multiwall carbon nanotube/NiCo2O4 core/shell structure for novel high-performance supercapacitors,” Journal of Materials Chemistry A, 2014, 2(14): 5100–5107.

[13] [13] N. A. Bakr, S. A. Salman, and A. M. Shano, “ Effect of Co doping on structural and optical properties of NiO thin films prepared by chemical spray pyrolysis method,” International Letters of Chemistry, Physics and Astronomy, 2015, 2: 15–30.

[14] [14] O. A. Hammadi, “Characterization of SiC/Si heterojunction fabricated by plasma-induced growth of nanostructured silicon carbide layer on silicon surface,” Iraqi Journal of Applied Physics, 2016, 12(2): 9–13.

[15] [15] N. S. Umeokwonna, A. J. Ekpunobi, and P. I. Ekwo, “Effect of cobalt doping on the optical properties of nickel cobalt oxide nanofilms deposited by electrodeposition method,” International Journal of Technical Research and Applications, 2015, 3(4): 347–351.

[16] [16] S. Sahoo, S. Ratha, and C. S. Rout, “Spinel NiCo2O4 nanorods for supercapacitor applications,” American Journal of Engineering & Applied Sciences, 2015, 8(3): 371–379.

[17] [17] O. A. Hammadi, “Characteristics of heat-annealed silicon homojunction infrared photodetector fabricated by plasma-assisted technique,” Photonic Sensors, 2016, 6(4): 345–350.

[18] [18] O. A. Hammadi, M. K. Khalaf, F. J. Kadhim, and B. T. Chiad, “Operation characteristics of a closed-field unbalanced dual-magnetrons plasma sputtering system,” Bulgarian Journal of Physics, 2014, 41(1): 24.33.

[19] [19] O. A. Hammadi, M. K. Khalaf, and F. J. Kadhim, “Silicon nitride nanostructures prepared by reactive sputtering using closed-field unbalanced dual magnetrons,” Proceedings of the Institution of Mechanical Engineers Part L: Journal of Materials Design & Applications, 2017, 231(5): 479–487.

[20] [20] O. A. Hammadi, M. K. Khalaf, and F. J. Kadhim, “Fabrication of UV photodetector from nickel oxide nanoparticles deposited on silicon substrate by closed-field unbalanced dual magnetron sputtering techniques,” Optical & Quantum Electronics, 2015, 47(2): 1.9.

[21] [21] O. A. Hammadi, M. K. Khalaf, and F. J. Kadhim, “Fabrication and characterization of UV photodetectors based on silicon nitride nanostructures prepared by magnetron sputtering,” Proceedings of the Institution of Mechanical Engineers Part N: Journal of Nanoengineering & Nanosystems, 2015, 230(1): 32.36.

[22] [22] A. A. Anber and F. J. Kadhim, “Preparation of nanostructured SixN1-x thin films by DC reactive magnetron sputtering for tribology applications,” Silicon, 2017, pp. 1–4.

[23] [23] M. A. Hameed and Z. M. Jabbar, “Preparation and characterization of silicon dioxide nanostructures by DC reactive closed-field unbalanced magnetron sputtering,” Iraqi Journal of Applied Physics, 2016, 12(4): 13–18.