Structure–Optical Property Correlation of Co-Doped TiO₂ and ZnO Nanofillers for Advanced Functional Composite Applications

Year : 2026 | Volume : 14 | Special Issue 01 | Page : 1374 1394
    By

    Anil Kumar,

  • Swati,

  • Niharika,

  1. Associate Professor, Department of Applied Science, Bharati Vidyapeeth’s College of Engineering, New Delhi, India
  2. Assistant Professor, Department of Chemistry, Baba Mastnath University, Rohtak, Haryana, India
  3. Research Scholar, Department of Chemistry, Baba Mastnath University, Rohtak, Haryana, India

Abstract

This study investigates the enhancement of the structural and optical properties of titanium dioxide (TiO₂) and zinc oxide (ZnO) nanoparticles through cobalt (Co) doping. Pristine TiO₂ and ZnO are widely studied metal oxides; however, their large band gaps and limited visible-light absorption restrict their performance in optoelectronic, photocatalytic, and environmental applications. Co doping is employed as an effective strategy to overcome these limitations by inducing band-gap narrowing, creating defect-related electronic states, and modifying the crystalline and morphological features of the host materials. TiO₂ and ZnO nanoparticles were synthesized using sol–gel and co-precipitation methods, respectively, allowing controlled dopant incorporation and uniform particle distribution. The successful substitution of Co ions into the TiO₂ and ZnO lattices was confirmed through comprehensive characterization techniques, including X-ray diffraction (XRD), UV–visible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). Structural analysis revealed that TiO₂ retained its anatase phase, while ZnO preserved its hexagonal wurtzite structure, indicating high phase stability even after doping. Optical studies demonstrated a noticeable red shift in absorption edges and enhanced visible-light absorption, attributed to Co-induced defect levels and altered electronic structures. Morphological analysis showed improved crystallinity and reduced particle agglomeration in the doped samples. Furthermore, Co-doped nanoparticles exhibited enhanced catalytic efficiency and structural robustness compared to their undoped counterparts. The results highlight the potential of Co-doped TiO₂ and ZnO as energy-efficient and environmentally friendly nanomaterials. In addition, these doped metal-oxide nanoparticles can function as effective Nano fillers in polymer and hybrid composite systems, significantly improving optical performance, photocatalytic activity, and environmental remediation efficiency.

Keywords: Cobalt doping, Titanium dioxide, Zinc oxide, Band gap reduction, Sol-gel synthesis, Photocatalysis.

[This article belongs to Special Issue under section in Journal of Polymer & Composites (jopc)]

How to cite this article:
Anil Kumar, Swati, Niharika. Structure–Optical Property Correlation of Co-Doped TiO₂ and ZnO Nanofillers for Advanced Functional Composite Applications. Journal of Polymer & Composites. 2026; 14(01):1374-1394.
How to cite this URL:
Anil Kumar, Swati, Niharika. Structure–Optical Property Correlation of Co-Doped TiO₂ and ZnO Nanofillers for Advanced Functional Composite Applications. Journal of Polymer & Composites. 2026; 14(01):1374-1394. Available from: https://journals.stmjournals.com/jopc/article=2026/view=238555


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Special Issue Subscription Review Article
Volume 14
Special Issue 01
Received 03/02/2026
Accepted 21/02/2026
Published 05/03/2026
Publication Time 30 Days
50

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