Electrically Adjustable, Super Adhesive Force of a Superhydrophobic Aligned MnO2 Nanotube Membrane

摘要: A superhydrophobic membrane of MnO2 nanotube arrays on which a water droplet can be immobilized by application small DC bias, despite large contact angle, is reported. For 3 mu L droplet, the measured adhesive force increases monotonically with increasing negative voltage, reaching maximum 130 N at 22 V, 25 times original value. It follows that nearly spherical controllably pinned substrate, even if substrate turned upside down. Moreover, electrically adjustable adhesion strongly polarity-dependent: only five-fold increase found when positive bias V applied. This remarkable electrically-controlled property ascribed to change in geometry between and array, droplets exhibit different continuities three-phase line. As modulation this manner situ, fast, efficient environmentally-friendly, kind smart material properties has wide variety applications biotechnology lab-on-chip devices.