1. Materials Science and Technology of Polymers; MESA Institute for Nanotechnology; University of Twente; P.O. Box 217 Enschede 7500 AE The Netherlands
2. Nanoionics; MESA Institute for Nanotechnology; University of Twente; P.O. Box 217 Enschede 7500 AE The Netherlands
3. Centre for Biomimetic Sensor Science; School of Materials Science and Engineering; Nanyang Technological University; Singapore 637553 Singapore