Bridging Molecular Modeling Insights and Experimental Findings: A Comparative Study on Surfactant Effects in Al₂O₃...

Area of Science:

• Materials Science
• Nanotechnology
• Physical Chemistry

Background:

• Nanofluids offer enhanced thermal properties for various applications.
• Surfactants are crucial for stabilizing nanoparticles in base fluids.
• Understanding nanoparticle-surfactant interactions is key to optimizing nanofluid performance.

Purpose of the Study:

• To prepare and characterize water-based Al2O3 nanofluids using six different surfactants.
• To investigate the impact of surfactant type on colloidal stability and thermophysical properties.
• To model nanoparticle-surfactant interactions using Density Functional Theory (DFT).

Main Methods:

• Preparation of Al2O3 nanofluids with anionic, cationic, and nonionic surfactants (SDS, CTAC, PVP, Tween 80, PVA, Triton X-100).
• Measurement of zeta potential and particle size for electrostatic colloidal stability assessment.
• DFT modeling to analyze nanoparticle-surfactant interactions and interaction Gibbs free energy.
• Measurement of thermophysical properties (e.g., thermal conductivity, viscosity).

Main Results:

• Surfactant type significantly influences the colloidal and thermophysical properties of Al2O3 nanofluids.
• Al2O3-SDS and Al2O3-CTAC nanofluids exhibited high zeta potential and thermal conductivity.
• These selected nanofluids also demonstrated low viscosity and particle size, indicating good stability.

Conclusions:

• Al2O3-SDS and Al2O3-CTAC nanofluids are suitable for cooling applications.
• The study highlights the importance of surfactant selection for optimizing nanofluid performance.
• DFT analysis provides molecular-level insights into stability and interactions.