Structural Classification of Sol–Gel Synthesized TiO2 Nanoparticle Variants: An Integrated Multi-Descriptor XRD Framework for Theoretical Functional Domain Assignment
Author(s): Khyati Mody 1,* and I. B. Patel 2
Authors Affiliations:
1, 2 Department of Physics, Veer Narmad South Gujarat University, Surat – 395007, Gujarat, India
DOIs:10.2017/IJRCS/202604023 | Paper ID: IJRCS202604023Five variants (S1–S5) of anatase TiO2 nanoparticles were synthesized via the sol–gel method by systematically varying titanium isopropoxide concentration and calcination temperature (200–500 °C). An integrated multi-descriptor XRD framework — comprising Scherrer crystallite-size analysis, Williamson–Hall (W–H) microstrain extraction, dislocation-density estimation, specific surface-area (SSA) calculation, texture-coefficient analysis, and lattice-parameter refinement — was applied to the original experimental XRD data to derive a complete quantitative structural portrait of each variant. The structural descriptors extracted from these measurements serve as established theoretical predictors of functional behavior in metal-oxide semiconductor nanomaterials: SSA and defect density predict photocatalytic activity; oxygen-vacancy density and facet anisotropy predict gas-sensing response; grain size and microstrain predict mechanical and electrochemical stability. On the basis of the measured structural evidence, S3 — exhibiting maximum SSA (204 m2 g−1), microstrain (3.9 × 10−3), and dislocation density (20.66 × 1015 m−2) — is predicted to be the most suitable candidate for photocatalytic and hydrogen-evolution applications. Variants S2 and S5, showing elevated oxygen-vacancy density and high-energy facet exposure, are structurally predicted for resistive gas sensing. Variants S1 and S4, with large low-strain grains, are structurally predicted for protective coating and electrode applications. Phase-pure anatase was retained in all samples to 500 °C, attributed to oxygen-vacancy-mediated phase pinning. FE-SEM independently validated the XRD-derived size–morphology trends. The structural classification framework presented here is directly extensible to doped and composite TiO2 systems, and forms the theoretical foundation for Part II experimental validation.
Khyati Mody* and I. B. Patel (2026); Structural Classification of Sol–Gel Synthesized TiO2 Nanoparticle Variants: An Integrated Multi-Descriptor XRD Framework for Theoretical Functional Domain Assignment, International Journal of Research Culture Society, ISSN(O): 2456-6683, Volume – 10, Issue – 4, Available on – https://ijrcs.org/
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