A Bubble-free Electroosmotic Pump with Polyaniline-wrapped Platinum-coated Titanium Mesh Electrodes

We developed a bubble-free electroosmotic pump (EOP) with polyaniline-wrapped platinum-coated titanium mesh electrodes. These electrodes prepared by the chronopotentiometry (CP) method show a better redox performance, electrochemical activity and stability. The optimal CP parameters are 0.413 mA of anode current (current density, 1.5 mA/cm2), and 1800 s of anode time (polymerization time). The EOP, assembled with polyaniline-wrapped platinum-coated titanium mesh electrodes, shows a much better performance than that of platinum-coated titanium mesh electrodes. After modification of the electrodes, the flow rate at a voltage of 6 V for purity water increases from 26.9 µL/min to 87.6 µL/min, and the limiting hydrostatic pressure improves from 59.3 Pa/V to 113.9 Pa/V. The polyaniline-wrapped platinum-coated titanium mesh electrodes can also keep undamaged surface morphology and unaltered redox performance after a long time EOP performance test, which can make it suitable for bubble-free uses in microfluidic system, drug delivery, and cooling of microelectronic devices.