Diode-like single-ion track membrane prepared by electro-stopping
2001 (English)Article in journal (Refereed) Published
The prepn. of an asym. membrane in poly(ethylene terephthalate) (PET) is described, using a combination of chem. and electro-stopping. For this purpose, a single-ion-irradiated PET film is inserted into an electrolytic cell and etched from one side in 9 M sodium hydroxide while bathing the other side in a mixt. of 2 M KCl and 2 M HCOOH (1:1 by vol.), elec. retracting the OH- ions from the tip of the etch pit during pore break-through. When a preset current has been reached, the etch process is interrupted by replacing the etching soln. with acidic 1 M potassium chloride soln. After etching, the current-voltage (I-V) characteristic is detd. under sym. bathing conditions, immersing both sides of the membrane in KCl solns. of identical concn. (0.01-1 M) and pH (3-8). The I-V characteristic is strongly non-linear, comparable to that of an elec. diode. If the polarity during etching is reversed, pushing the OH- ions into the tip of the etch pit, the resulting pores are larger and the degree of asymmetry smaller. The importance of electro-stopping is compared with chem. stopping.
Place, publisher, year, edition, pages
2001. Vol. 184, 337-346 p.
Research subject Physics
IdentifiersURN: urn:nbn:se:uu:diva-111265OAI: oai:DiVA.org:uu-111265DiVA: diva2:285385