Synergistic effects of mixed anionic-cationic surfactants on the stability and thermophysical behavior of ferrite-based magnetic nanofluids
Journal of Molecular Liquids, cilt.458, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 458
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.molliq.2026.129786
- Dergi Adı: Journal of Molecular Liquids
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Chimica, Compendex, INSPEC, Academic Search Ultimate (EBSCO), Engineering Source (EBSCO)
- Anahtar Kelimeler: Colloidal stability, Ferrite nanoparticles, Magnetic nanofluid, Mixed surfactant, Thermal performance index
- Gazi Üniversitesi Adresli: Evet
Özet
In this study, ferrite-based magnetic nanofluids containing MnFe₂O₄, CoFe₂O₄, and Ni₀.₅ Co ₀.₅Fe₂O₄ nanoparticles were prepared using pure and mixed SDS/CTAB surfactant systems. The influence of ferrite composition and surfactant mixing ratio on the thermophysical, rheological, colloidal stability, and wettability characteristics of the nanofluids was investigated. Thermal conductivity increased by 8.19–9.6% compared with pure water, with the highest values obtained for Ni₀.₅ Co ₀.₅Fe₂O₄-based nanofluids. The SDS:CTAB ratio strongly affected viscosity, with the 1:1 mixture producing the highest viscosity values in MnFe₂O₄ and CoFe₂O₄ systems. Stability analyses indicated acceptable short-term colloidal stability during 7-day static storage, with absolute zeta potential values generally exceeding 30 mV. Mixed surfactant systems also improved wettability, with the lowest contact angle of 16.0° observed for the Ni₀.₅ Co ₀.₅Fe₂O₄ nanofluid. TPI analysis showed that nanofluid performance depends on the combined effects of thermal conductivity, volumetric heat capacity, and viscosity rather than thermal conductivity alone. Overall, both ferrite composition and surfactant ratio played critical roles in determining nanofluid performance. These formulations represent promising candidates for heat-transfer-fluid development, although further device-level validation is required for practical applications.