Paper Title
Omniphobic Hollow Fiber Membrane with Nanoparticles Deposition

Abstract
In this study, the hydrophobic surface of polytetrafluoroethylene (PTFE) hollow fiber membrane was enhanced to omniphobic by using coating the membrane surface with zinc oxide nanoparticles (ZnO-NPs) mixed with polyvinylidene fluoride-cohexafluoropropylene (PVDF-HFP) via universal spray technique. The morphology and performance of the membrane were characterized based on the spray cycle number which induced the thickness of the coating agent on the membrane surface. The sprayed was varied up to 4 cycles to represent which membrane with the most effective deposition of ZnO NPs in term of water contact angle and liquid entry pressure (LEPw). The results showed that the membrane that had been spray coated up to 4 cycles, referred as PTFE-4 portrayed a rough hierarchical re-entrant morphology which allowed it to achieve an omniphobic characteristic. The optimized membrane exhibits high water contact angle value of 170° and liquid entry pressure value of 2.6 bar. Fourier-transform infrared (FTIR) and energy dispersive analysis of X-rays (EDX) analysis also showed the successful chemical integration of the ZnO NPs on the commercial membrane. This study is important for the future of MD for treating wastewater containing low surface tension pollutants. Keywords - Hydrophobic membrane; Hollow fiber; Nanoparticles; Omniphobicity