Electropolymerization and Characterization of Poly (O-Phenylenediamine) Thin Films at Different pH


  • C. J. Nkamuo* Department of Science of Laboratory Technology, Federal Polytechnic Oko Anambra, Nigeria
  • A.O.C Nwokoye Department of Physics and Industrial Physics, Nnamdi Azikiwe University Awka Anambra, Nigeria
  • A. J. Ekpunobi Department of Physics with Electronics, Legacy University Okija, Anambra, Nigeria
  • N. L. Okoli Department of Industrial Physics, Chukwuemeka Odumegwu Ojukwu University, Uli, Anambra, Nigeria




Electropolymerization, PoPD, Thin film, pH variation


Poly -o- phenylenediamine (PoPD) was deposited as thin films on fluorine doped tin oxide (FTO) conducting substrates by electropolymerization technique using two electrodes at varying acidic pH values of the reaction medium. Dihydrogen sodium phosphate and disodium hydrogen phosphate were used for the preparation of phosphate buffer solution. pH values of 1.0, 1.5 and 2.0 were varied by adding phosphoric acid. 1.2V D.C supply voltage was used with the deposition time of five minutes. The prepared polymer samples were characterized using UV-Vis spectroscopy, Raman Spectroscopy, Scanning Electron Microscope (SEM), X – ray diffraction (XRD) techniques, profilometry and four point probe. The spectral results indicated that the synthesized PoPD film has a head to tail type arrangement with the benzenoid and quinoid structures in the phenazine – like backbone and the absorption bands showed a bathochromic shift. The results also showed that the deposited films have low reflectance and the pH values of the reaction medium affect reflective power of the film produced in such medium and the film deposited at strong acidic condition of (pH = 1.0) has the least reflective power. Also, the optical density (ΔOD) of the PoPD was determined as 0.64 which revealed that the polymer is electrochromic. More unevenly dispersed particles of the Poly (o - phenylenediamine) polymer were observed from the SEM images. The result of the XRD revealed that the samples are amorphous in nature. The results obtained from the Raman spectra confirmed that the PoPD thin film samples contained phenazine ring ladder – structure made of quinoids and benzenoids imine units. The values of the electrical conductivity showed that the PoPD samples fabricated are conducting polymers and pH affect the electrical properties of PoPD thin films.


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How to Cite

Nkamuo, C. J., Nwokoye, A., Ekpunobi, A., & Okoli, N. L. (2022). Electropolymerization and Characterization of Poly (O-Phenylenediamine) Thin Films at Different pH. Journal of Nano and Materials Science Research, 1, 49–57. https://doi.org/10.20221/jnmsr.v1i.6