, 44:26 | Cite as

The calculate of optical gap energy and urbach energy of Ni1−xCoxO thin films

  • Said BenramacheEmail author
  • Yacine Aoun
  • Said Lakel
  • Boubaker Benhaoua
  • Chahrazed Torchi


The effect of Co doping on optical, structural and electrical properties of Ni1−xCoxO thin films has been successfully deposited on glass substrate by Sol–Gel Sping coating technique. The main objective of this research is to study the Ni1−xCoxO thin films to determine the optical gap energy by various methods and compare of calculated values. The transmission spectra show that the Ni1−xCoxO thin films have a good optical transparency in the visible region. The optical gap energy was varied between 3.8 and 4.05 eV, which was determined by various methods and equations. These are found in the drawn of A, A2, α, α2 (Ahν)2 and (αhν)2 as a function of the photon energy , the suitable method to calculate the optical energy was observed for (Ahν)2 versus , but this method can not be related to the film thickness. The urbach energy of the Ni1−xCoxO thin films also was determined by the curves of LnA and Lnα as a function of photon energy . The deduce by LnA versus is also suitable to estimate the urbach energy. However, the Ni0.96Co0.04O thin films have a few defects with minimum value of urbach energy. XRD patterns of the Ni1−xCoxO thin films indicate that some films are polycrystalline with cubic structure. The electrical conductivity of our films is in the order of 8.2*10−3(Ω.cm)1.


NiO thin films co doping TCO sol–gel sping coating method 


  1. 1.
    Verma V and Katiyar M 2013 Effect of the deposition parameters on the structural and magnetic properties of pulsed laser ablated NiO thin films. Thin Solid Films 527: 369–376CrossRefGoogle Scholar
  2. 2.
    Chen S C, Kuo T Y, Lin Y C and Lin H C 2011 Preparation and properties of p-type transparent conductive Cu-doped NiO films. Thin Solid Films 519: 4944–4947CrossRefGoogle Scholar
  3. 3.
    Sharma R, Acharya A D, Shrivastava S B, Patidar M M, Gangrade M, Shripathi T and Ganesan V 2016 Studies on the structure optical and electrical properties of Zn-doped NiO thin films grown by spray pyrolysis. Optik 127: 4661–4668CrossRefGoogle Scholar
  4. 4.
    Benramache S and Aouassa M 2016 Preparation and Characterization of p-Type Semiconducting NiO Thin Films Deposited by Sol–Gel Technique. Journal of Chemistry and Materials Research 5(6): 119–122Google Scholar
  5. 5.
    Dendouga S, Benramache S and Lakel S 2016 Influence of film thickness on optical and electrical properties of Nickel Oxide (NiO) thin films. Journal of Chemistry and Materials Research 5(4): 78–84Google Scholar
  6. 6.
    Dini D, Halpin Y, Vos J G and Gibson E A 2015 The influence of the preparation method of NiO x photocathodes on the efficiency of p-type dye-sensitized solar cells. Coordination Chemistry Reviews 304–305: 179–201CrossRefGoogle Scholar
  7. 7.
    Cai G F, Gu C D, Zhang J, Liu P C, Wang X L, You Y H and Tu J P 2013 Ultra fast electrochromic switching of nanostructured NiO films electrodeposited from choline chloride-based ionic liquid. Electrochimica Acta 87: 341–347CrossRefGoogle Scholar
  8. 8.
    Nwanya A C, Offiah S U I, Amaechi C, Agbo S, Ezugwu S C, Sone B T, Osuji R U, Maaza M and Ezema F I 2015 Electrochromic and electrochemical supercapacitive properties of Room Temperature PVP capped Ni(OH)2 /NiO Thin Films. Electrochimica Acta 171: 128–141CrossRefGoogle Scholar
  9. 9.
    Romero R, Martin F, Ramos-Barrado J R and Leinen D 2010 Synthesis and characterization of nanostructured nickel oxide thin films prepared with chemical spray pyrolysis. Thin Solid Films 518: 4499–4502CrossRefGoogle Scholar
  10. 10.
    Chtouki T, Soumahoro L, Kulyk B, Bougharraf H, Kabouchi B, Erguig H and Sahraoui B 2017 Comparison of structural, morphological, linear and nonlinear optical properties of NiO thin films elaborated by Spin-Coating and Spray Pyrolysis. Optik 128: 8–13CrossRefGoogle Scholar
  11. 11.
    Deokate R J, Kalubarme R S, Park C J and Lokhande C D 2017 Simple Synthesis of NiCo2O4 thin films using Spray Pyrolysis for electrochemical supercapacitor application: A Novel approach. Electrochimica Acta 224: 378–385CrossRefGoogle Scholar
  12. 12.
    Yu Y, Li X, Shen Z, Zhang X, Liu P, Gao Y, Jiang T and Hua J 2017 Restrain recombination by spraying pyrolysis TiO2 on NiO film for quinoxaline-based p-type dye-sensitized solar cells. Journal of Colloid and Interface Science 490: 380–390CrossRefGoogle Scholar
  13. 13.
    Offiah S U, Nwodo M O, Nwanya A C, Ezugwu S C, Agbo S N, Ugwuoke P U, Osuji R U, Malik M and Ezema F I 2014 Effects of post-thermal treatments on morphological and optical properties of NiO/Ni(OH)2 thin films synthesized by solution growth. Optik 125: 2905–2908CrossRefGoogle Scholar
  14. 14.
    Chen S C, Kuo T Y, Lin Y C, Hsu S W and Lin H C 2013 Effect of palladium content on microstructures, electrical and optical properties of NiO films by rf sputtering. Thin Solid Films 549: 50–53CrossRefGoogle Scholar
  15. 15.
    Xia X H, Tu J P, Zhang J, Wang X L, Zhang W K and Huang H 2008 Morphology effect on the electrochromic and electrochemical performances of NiO thin films. Electrochimica Acta 53: 5721–5724CrossRefGoogle Scholar
  16. 16.
    Castro-Hurtado I, Herrán J, Mandayo G G and Castaño E 2011 Studies of influence of structural properties and thickness of NiO thin films on formaldehyde detection. Thin Solid Films 520: 947–952CrossRefGoogle Scholar
  17. 17.
    Dridi R, BenAmor M, Mahdhi N, Amlouk A, Boubaker K and Amlouk M 2016 Structural, optical and conductivity studies of amorphous ZnxNi1−xO thin films along with wettability and photocatalytic tests. Journal of Non-Crystalline Solids 449: 1–11CrossRefGoogle Scholar
  18. 18.
    Al-Ghamdi A A, Abdel-wahab M, Sh Farghali A A and Hasan P M Z 2016 Structural, optical and photo-catalytic activity of nanocrystalline NiO thin films. Materials Research Bulletin 75: 71–77CrossRefGoogle Scholar
  19. 19.
    Benramache S and Benhaoua B 2012 Influence of substrate temperature and Cobalt concentration on structural and optical properties of ZnO thin films prepared by Ultrasonic spray technique. Superlattices and Microstructures 52: 807–815CrossRefGoogle Scholar
  20. 20.
    Kumar N S, Bangera K V, Ananda C and Shivakumar G K 2013 Properties of ZnO:Bi thin films prepared by spray pyrolysis technique. Journal of Alloys and Compounds 578: 613–619CrossRefGoogle Scholar
  21. 21.
    Benramache S and Benhaoua B 2012 Influence of annealing temperature on structural and optical properties of ZnO: In thin films prepared by ultrasonic spray technique. Superlattices and Microstructures 52: 1062–1070CrossRefGoogle Scholar
  22. 22.
    Benramache S, Benhaoua B and Chabane F 2012 Effect of substrate temperature on the stability of transparent conducting cobalt doped ZnO thin films. Journal of Semiconductors 33: 093001–093004CrossRefGoogle Scholar
  23. 23.
    Abdur Rahman M, Radhakrishnan R and Gopalakrishnan R 2018 Structural, Optical, Magnetic and antibacterial properties of Nd doped NiO nanoparticles prepared by co-precipitation method. Journal of Alloys and Compounds 742: 421–429CrossRefGoogle Scholar
  24. 24.
    Sajilal K and Moses Ezhil Raj A 2016 Effect of thickness on physico-chemical properties of p-NiO(bunsenite) thin films prepared by the chemical spray pyrolysis(CSP) technique. Optik 127: 1442–1449CrossRefGoogle Scholar
  25. 25.
    Cao J, Wang Z, Wang R, Liu S, Fei T, Wanga L and Zhang T 2015 Synthesis of core–shell α-Fe2O3@NiO nanofibers with hollow structures and their enhanced HCHO sensing properties. Journal of Materials Chemistry A 3: 5635–5641CrossRefGoogle Scholar

Copyright information

© Indian Academy of Sciences 2019

Authors and Affiliations

  • Said Benramache
    • 1
    Email author
  • Yacine Aoun
    • 1
    • 2
  • Said Lakel
    • 3
  • Boubaker Benhaoua
    • 4
  • Chahrazed Torchi
    • 3
  1. 1.Laboratoire de Physique photonique et nanomatériaux multifonctionnelsUniversity of BiskraBiskraAlgeria
  2. 2.Mechanics DepartmentEl-Oued UniversityEl-OuedAlgeria
  3. 3.Material Sciences DepartmentBiskra UniversityBiskraAlgeria
  4. 4.Unité de Recherche en Energies Renouvelables en zones aridesEl-OuedAlgeria

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