Synthesis of cobalt oxides modified with palmitic acid and acetic acid and their application as a hydrophobic and self-cleaning coating

Document Type : Original Article


Urmia, Urmia University, Faculty of Basic Sciences and Chemistry, Department of Chemistry


In the present research work, at first, the preparation of cobalt oxide nanoparticles was done by
sol–gel auto-combustion method. The characteristic properties of the powder were done by techniques of XRD, FT-IR, AFM and FESEM techniques, which revealed the structural, functional groups and particle size and morphology of the sample, respectively. X-ray diffraction show formation of the Co3O4 nanoparticles
with spinel structure. The average crystallite size of the sample was obtained 5-10 nm by using the Scherrer formula, respectively. FT-IR spectrum
confirm the formation of cobalt oxide bonds. FESEM images show that the shape and
size of nanoparticles produced by a sol – gel were 20-50 nm with a cuboid particle shape. After preparation of cobalt oxide nanoparticles, we used them to produce super-hydrophobic surface. The produced cobaltite nanoparticles were coated on the glass substrate and then put in the furnace. In the end,
Palmitic acid and Acetic acid as samples of organic acids were applied for modification of coating.. Different ratio of the acides were used to prepare the coating. The best super hydrophobic coating was resulted for the coating modified with the 1:1 ration of palmetic acid and acetic acid. The value of contact angle (CA) for the water droplet on the surface of best coating was 158.2, indicating that the coating exhibit the super-hydrophobicity property. The self-cleaning property of the coating was tested by dispersing of mud on it for 48 h and after that no mud adhesive on the coating, indicating the self-cleaning properties of the modified cobaltite coating.


[1] VA Ganesh, HK Raut, AS Nair, S. Ramakrishna. A review on self-cleaning coatings. J. Mater. Chem. 21 )2011(16304.
[2] A Solga Z, Cerman, BF Striffler, M Spaeth, W Barthlott. The dream of staying clean: Lotus and biomimetic surfaces. Bioinspiration & Biomimetics. 16 )2007(126.
[3] N. Ehsan, M. Mahdi, J. Of Applied Chemistry, Special issue of the second seminar of applied chemistry in Iran, September 2017, in Persian.
[4] Ž Senić, S Bauk, M Vitorović-Todorović, N Pajić, A Samolov, D. Rajić, Application of TiO2 nanoparticles for obtaining self-decontaminating smart textiles. Sci. Tech. Rev. 61 (2011) 63.
[5] T Nishino, M Meguro, K Nakamae, M Matsushita, Y Ueda. The lowest surface free energy based on− CF3 alignment. Langmuir. 22  (1999) 4321.
[6] IA Larmour, SE Bell, GC Saunders. Remarkably simple fabrication of superhydrophobic surfaces using electroless galvanic deposition. Angewandte Chemie International Edition. 26 ( 2007)1710.
[7] A. Milionis, C.S. Sharma, R. Hopf, M. Uggowitzer, I.S. Bayer, D. Poulikakos, Engineering fully organic and biodegradable superhydrophobic materials, Adv. Mater. Interfaces (2018) 1801202.
[8] A. Davis, Y.H. Yeong, A. Steele, I.S. Bayer, E. Loth, Superhydrophobic nanocomposite surface topography and ice adhesion, ACS Appl. Mater. Interfaces 6 (12) (2014) 9272.
[9] P. Calcagnile, D. Fragouli, I.S. Bayer, G.C. Anyfantis, L. Martiradonna, P.D. Cozzoli, R. Cingolani, A. Athanassiou, Magnetically driven floating foams for the removal of oil contaminants from water, ACS Nano 6 (6) (2012) 5413.
[10] S. Latthe, C. Terashima, K. Nakata, A. Fujishima, Superhydrophobic surfaces developed by mimicking hierarchical surface morphology of Lotus leaf, Molecules 19 (4) (2014) 4256.
[11] V.A. Ganesh, H.K. Raut, A.S. Nair, S. Ramakrishna, A review on self-cleaning coatings, J. Mater. Chem. 21 (41) (2011) 16304.
[12] S. Liu, X. Liu, S.S. Latthe, L. Gao, S. An, S.S. Yoon, B. Liu, R. Xing, Self-cleaning transparent superhydrophobic coatings through simple sol–gel processing of fluoroalkylsilane, Appl. Surf. Sci. 351 (2015) 897.
[13] H. Ogihara, J. Xie, T. Saji, Factors determining wettability of superhydrophobic paper prepared by spraying nanoparticle suspensions, Colloids Surf. A Physicochem. Eng. Asp. 434 (2013) 35.
[14] A. Abbasi, M. Ahmadi Golsefidi, M. Mohammad Beigi, N. Sadri,M. Abroudi, Facile Fabrication of Co3O4 Nanostructures as an Effective Photocatalyst for Degradation and Removal of Organic Contaminants, J. Nanostruct. 8 (2018) 89.
[15] Jonathan Rosen, G. S. Hutchings, F. Jiao, Synthesis, structure, and photocatalytic properties of ordered mesoporous metal-doped Co3O4, J. Catal., 310 (2014) 2.
[16] H. Chen, C. Xue, D. Cui, M. Liu, Y. Chen, Y. Li, W. Zhang, Co3O4–Ag photocatalysts for the efficient degradation of methyl orange, RSC Adv., 10 (2020) 15245.
[17] S.A. Hosseini, A. Niaei, D. Salari, Preparation and characterization of nano- and non-nanoscale Co3O4 spinels obtained from different methods and study of their performance in combustion of aromatics from polluted air-A comparison with Pt/γ -Al2O3 performance, J. Environ. Sci. Health, Part A 47 (2012) 1728.