Electrochemical Pump Consisting of Cu~(2+)-Poly(acrylic acid) Gel

摘要

An electrochemical pump consisting of poly(acrylic acid) incorporating Cu~(2+) ion was developed. The pump discharges and charges liquid at the level of a few hundred of picoliter per second upon expansion and contraction of the gel induced by reduction and oxidation of the copper, respectively. The pump discharged ca. 5 μl of water at -1.3 V vs. Ag/AgCl for 3 h, whereas charged ca. 1.2 μl at +1.0 V for 3 h. At constant currents of-4.4 and +4.4 μA cm~(-2), the volumes of water discharged and charged were found to be nearly proportional to the charge at ca. 0.10 cm~3 C~(-1) for both reduction and oxidation processes, except for an initial stage of the electrolysis. Further, upon repeated galvanostatic electrolyses, the same volume-charge slopes were obtained. These results indicate a reversibility and reproducibility of the pump.