Functional mapping of 3D electrically conductive skin

• Main Author: Zeng, Wen Qiu
• Other Authors: Grzegorz Lisak
• Format: Final Year Project
• Language: English
• Published: 2017
• Subjects: DRNTU::Engineering::Civil engineering
• Online Access: http://hdl.handle.net/10356/71486
• Institution: Nanyang Technological University

Recognition and visualization of diverse skin patterns on a flexible gold-coated substrate surface is performed by means of direct electrochemical deposition to regions of bare substrate surface between the sebaceous skin print residue. The study of skin topography has a remarkable importance for biometric identification. Specially, the ease of collection of fingerprint evidence is widely in used as a technique to identify and verify an individual. In this project, a novel direct on-body electro-polymerization approach has been developed for the fabrication of a 3- dimensional (3D) conducting functional skin pattern deposited on a flexible gold-coated surface from aqueous solutions containing 0.01M 3,4-ethylenedioxythiophene (EDOT) and 0.1 M Poly (sodium 4-styrenesulfonate) (PSS). The decision of employing Poly (3,4- ethylenedioxythiophene) (PEDOT:PSS) in fabricating 3D and conducting skin print was taken due to their superior chemical stability and electrical properties. To perform a diverse skin mapping, a conventional off-body electrochemical polymerization was also performed by using a three-electrode configuration system (reference electrode, counter electrode and working electrode), to increase the feasibility of this approach on different skin features such as hand, fingerprint, face, forehead, scars and moles. Various characterization methods are employed on oxidized (p-doped) PEDOT films in a chemically active aqueous solution, to investigate the electrochemical properties and surface morphology by cyclic voltammetry, scanning electron microscope (SEM), and field emission scanning electron microscope (FESEM). Furthermore, PEDOT samples were fabricated on glassy carbon substrate by varying the deposition time from 415s to 1015s at a constant current density of 0.2mA/cm2. Scanning electron microscope revealed that the longer the deposition time, the thicker the polymer films. It also revealed that the thickness of the polymer film is all dependent over several critical parameters: current density, concentration of dopant and the deposition time.