Abstract
Nanoporous membranes with platinum (Pt) and gold (Au) coated on opposite faces can autonomously pump fluid in the presence of hydrogen peroxide, but the physics is not fully understood. Here, we show with simulation results that the self-pumping flow rate can be considerably increased by avoiding the overlap of electric double layers (EDL) inside pores. Due to catalytic electrochemical reactions on Pt and Au, hydrogen ions (H+) are generated and depleted on opposite sides of the membrane, establishing a self-generated electric field and associated electro-osmotic flow through the pores. By optimizing the pore radius, EDL overlap is avoided and an area-averaged self-pumping flow speed of 23 µm/s can be achieved, which is 20 times higher than previously reported. By conducting the first-ever physico-chemical computational model of self-pumping membranes, this work reveals the mechanism of self-pumping flow in porous two-sided “Janus” membranes and highlights the potential of developing biomimetic membranes and lab-on-chip devices that can precisely and remotely control fluid flow in pores or channels in an “on/off” manner.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have