METHOD OF PLASMA MEMBRANE MODIFICATION IN PRODUCTION OF MEMBRANE-ELECTRODE UNIT OF FUEL ELEMENT Russian patent published in 2015 - IPC H01M8/10 

FIELD: chemistry.

SUBSTANCE: invention relates to field of chemical sources of current, namely to methods of modifying polymer perfluorinated sulphocationite membranes, used in manufacturing membrane-electrode units (MEU), applied in fuel elements (FE) of various types, including portable electronic devices. Method of plasma membrane modification consists in transition of membrane into H⁺-form by boiling in sulphuric acid with further washing in de-ionised water, after which plasma processing of membrane is performed, with the following plasma-chemical modification of cathode side of membrane in atmosphere of inert gas and fluorinating agent. Polymer perfluorinated sulphocationite membranes of Nafion, MF-4SK type are used. Plasma processing of membrane is performed under conditions of continuous, or radio-frequency, or pulse plasma discharge. Constant current magnetron possesses the highest efficiency of plasma localisation near the surface of membrane. Dose of the membrane surface irradiation constitutes 1-2 kJ/cm², discharge power in plasma processing is 50-200 W. Time of plasma processing is 5-50 min. Rate of membrane rotation in plasma processing constitutes 5-20 rev/min.

EFFECT: reduced consumption of platinum group metals, improved contact between catalyst layer and membrane, increased stability of FE operation, decreased degree of permeability by methanol, increased mechanical strength and chemical stability of polymer membrane.

15 cl, 2 dwg