Recently, there has been increasing attention on bipolar electrodes which work as a wireless electrode in the presence of external electric field.¹ Since bipolar electrodes are driven with low concentration of supporting electrolytes, an electrosynthesis process using bipolar electrode can reduce the amount of waste after the electrolysis. We have already reported the electrochemical fluorination using a bipolar electrode system, in which the amount of supporting electrolyte used could be reduced to less than 1/100 compared to the conventional method.² On the other hand, when pumping the solution with low concentration of supporting electrolyte into a narrow channel, potential difference between inlet and outlet of the channel, i.e., a streaming potential, generates to potentially be a driving energy for a bipolar electrode system.³

In this study, we have investigated the conditions in a flow cell to generate enough streaming potentials for electrode reactions. Then, electropolymerization of aromatic monomers such as pyrrole and 3,4-ethylenedioxythiophene has been achieved by driving a bipolar electrode using a streaming potential.

References

1. N. Shida, Y. Zhou, S. Inagi, Acc. Chem. Res., 2019, 52, 2598–2608.
2. K. Miyamoto, H. Nishiyama, I. Tomita, S. Inagi, ChemElectroChem, 2019, 6, 97–100.
3. I. Dumitrescu, R. K. Anand, S. E. Fosdick, R. M. Crooks, J. Am. Chem. Soc., 2011, 133, 4687–4689.