Cutaneous Respiration Inspired Porous Seawater Electrodes

Abstract

Electron transfer between oxygen molecules and electrodes is important for various underwater devices. However, the combined difficulties in renewing dissolved oxygen molecules and bridging their electron transfer are still challenges for current electrodes. In this work, we report a cutaneous respiration inspired strategy by using porous seawater as the active liquid medium. Porous seawater and solid electrodes are packed by dialysis membranes to form porous seawater electrodes. The dialysis bag allows capturing oxygen molecules from external environment to renew dissolved oxygen molecules. The porous seawater electrode can bridge electron transfer between the renewed oxygen and the electrode through Na-ion intercalation/de-intercalation under artificial waves. The seawater batteries made with the porous seawater electrodes supply continuous electricity with an output voltage at 5 V with boosting chips. This strategy is expected to enhance performance of the underwater devices which rely on power supply from metal-oxygen batteries and may inspire other technologies which are based on electron transfer between dissolved gas molecules and solid electrodes.

Keywords: Porous liquids, porous seawater, seawater battery, dissolved gas, electrons transfer, Prussian blue analogues, metal-organic frameworks, cutaneous respiration