Effect of nano-SiO2 content on morphology and performance of PVDF/SiO2 hybrid membranes: Synergistic enhancement in antifouling and anti-compaction performance

• Membrane morphology and phase separation mechanism are controlled by SiO 2 dosage. • Hybrid membranes with 3 wt% SiO 2 has optimal performance. • 3 wt% SiO 2 boosts compaction resistance & antifouling simultaneously. • Hybrid membranes is suitable for high-pressure water treatment. Polyvinylidene fluoride (PVDF) membranes suffer from strong hydrophobicity-induced fouling and compaction, limiting their application. Herein, PVDF/SiO 2 hybrid membranes were fabricated via thermally induced phase separation (TIPS) to investigate the effects of nano-SiO 2 content (0–6 wt%) on their morphology and performance. Results showed that SiO 2 incorporation significantly improved hydrophilicity (contact angle reduced from 107.9° to 92.5°) , increased porosity by 14.5% (58.8%→67.3%) and improved pure water flux by 231.5% (from 63.4 w to 210.2 L·m −2 ·h −1 of 3 wt% of SiO 2 dosage). The membranes with 3 wt% dosage of SiO 2 exhibited the smallest, most uniform spherulites, and optimal synergistic enhancement in antifouling and anti-compaction performance with deformation rate of 37.1% (vs. 49.4% for neat PVDF) and > 60% reduction in irreversible fouling resistance. Hermia model confirmed reversible cake layer fouling. Even at 6 wt% SiO 2 (with aggregation), performance remained superior to neat PVDF. This study provides a strategy for designing durable PVDF membranes for high-pressure water treatment.