Two-step etch method to improve the filtering performance of nuclear track membrane

摘要

A method for the fabrication of double-cone shape pores in polyethylene terephthalate (PET)-based nuclear track membranes (NTMs) is presented here. PET films of 25 μm thickness were irradiated with Bi ions (kinetic energy 9.5 MeV/u, fluence 5×10~7 ions/cm~2) at room temperature under vacuum at the Heavy Ion Research Facility (HIRFL) in Lanzhou. Then using two-step etch method to fabricate the NTMs with double-cone pores. Comparing the filtering flux by using Yellow-river water between the double-cone shape and regular, cylindrical shape in the experiment. Filtering flux through simulation by ANSYS Fluent and the water test results are also compared. The experimental results show that the flux of double-cone shape is significantly 5 times higher than that of cylindrical shape. And NTMs with inner pore size of 450 nm can effectively separate bacteria by an average of 99.90% (particle counter) in raw water.