CO-ION LEAKAGE THROUGH BIPOLAR MEMBRANES INFLUENCE ON IV RESPONSES AND WATER-SPLITTING EFFICIENCY

The influence of co-ion leakage through a bipolar membrane on both I-V response and current efficiency of water dissociation was studied. Th e monofilm bipolar membrane was synthetized from a pretreated ETFE fil m functionalized by quaternized ammonium groups on one side and sulpho nic groups on the other. The co-ion leakage of this bipolar membrane i mmersed in NaCl solutions was measured by means of radiotracers. The r esults showed that the greater the co-ion leakage, the lower was the c urrent efficiency of water dissociation. A theoretical analysis of ion transfer through the bipolar membrane pointing out the effect of boun dary layer on the limiting leakage current is presented.