Simple fabrication method of flexible carbon nanotube electrodes using inkjet and transfer printing methods for dopamine detection

Abstract

Modern light wearable electrical devices require flexible, conductive materials for the development of portable and/or wearable devices. In this study, a flexible carbon nanotube (CNT) electrode is prepared, and the conductive CNTs are deposited on a flexible polydimethylsiloxane (PDMS) substrate using a combination of inkjet printing and transfer printing methods. Aqueous CNT ink is printed on a commercial overhead projector film. The subsequent deposition of a thin PDMS layer and peeling the layer off resulted in the production of a flexible PDMS film with conductive CNT patterns. The thickness of the prepared electrode increased by ∼1.2 µm after every 10 prints, and the sheet resistance decreased rapidly from 14.7 MΩ/sq to 913 kΩ/sq after 20 and 50 prints, respectively. The construction of a simple foldable electrical circuit and its application to the electrochemical sensing of dopamine using flexible electrodes are demonstrated. These flexible electrodes can be easily fabricated while displaying designer functionality.