In-depth stability analysis and optimization of ultrasonication duration for novel TiO2-seaweed nanolubricants using the one-factor-at-a-time (OFAT) response surface methodology

The advancement of electric vehicle (EV) technology necessitates advanced, sustainable lubrication solutions. This study introduces an eco-friendly TiO 2 nanolubricant stabilized by a seaweed-based biolubricant, a renewable resource that eliminates the need for synthetic surfactants. Employing Response Surface Methodology (RSM) with a One-Factor-At-a-Time (OFAT) design, the ultrasonication duration was systematically optimized to maximize dispersion stability, which was quantified by Ultraviolet-Visible (UV-Vis) spectrophotometry. The results identified an ultrasonication time of 60 minutes (min) as optimal, a finding that was predicted with high accuracy by a quadratic model (R 2 = 0.9644). This optimization provides a critical, energy-efficient processing parameter for developing high-performance nanolubricants. The findings establish seaweed biolubricant as a viable stabilizer and present a statistically robust framework for the reproducible preparation of nanolubricants, thereby advancing the integration of green materials into tribological applications for EVs.