Abstract A non‐volatile conjugated polymer‐based electrochemical memristor (cPECM), derived from sodium 4‐[(2,3‐dihydrothieno[3,4‐b][1,4]dioxin‐2‐yl)methoxy]butane‐2‐sulfonate (S‐EDOT), is fabricated through roll‐to‐roll printing and exhibited neuromorphic properties. The 3‐terminal device employed a “read” channel where conductivity of the water‐soluble, self‐doped S‐PEDOT is equated to synaptic weight and was electrically decoupled from the programming electrode. For the model system, a +2500 mV programming pulse of 100 ms duration resulted in a 0.136 μS resolution in conductivity change, giving over 1000 distinct conductivity states for one cycle. The minimum programming power requirements of the cPECM was 0.31 pJ mm−2and with advanced printing techniques, a 0.1 fJ requirement for a 20 μm device is achievable. The mathematical operations of addition, subtraction, multiplication, and division are demonstrated with a single cPECM, as well as the logic gates AND, OR, NAND, and NOR. This demonstration of a printed cPECM is the first step toward the implementation of a mass produced electrochemical memristor that combines information storage and processing and may allow for the realization of printable artificial neural networks.
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Spatially Directed Functionalization by Co-electropolymerization of Two 3,4-ethylenedioxythiophene Derivatives on Microelectrodes within an Array
Electrodeposited conductive copolymer films with predictable relative properties (quantities of functional groups for further modification and capacitance) are of interest in sensors, organic electronic materials and energy applications. Potentiodynamic copolymerization of films in aqueous solutions of two different thiophene derivatives, (2,3-dihydrothieno[3,4-b]dioxin-2-yl)methanol (1) and 4-((2,3-dihydrothieno[3,4-b][1,4]dioxin-2-yl)-methoxy)-4-oxobutanoic acid (2), containing 0.02 M total monomer (0, 25, 34, 50, 66, 75, 100 mol%2), 0.05 M sodium dodecyl sulfate, and 0.1 M LiClO4, on gold microelectrodes in an array was investigated. Decreasing monomer deposited (m)from 0 to 100 mol%2is attributed to a decreasing pH that inhibits electropolymerization. Molar ratios of1and2in the films, determined by micro-attenuated total reflectance Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy, tracks closely with the ratio in the deposition solutions. Capacitances measured from cyclic voltammetry in aqueous buffer and electron transfer of ferrocyanide at the films are unaffected by copolymer composition, except for the 100 mol%2case. Ratios of reverse-to-forward faradaic peak currents suggest that films with high content of1expand in the anodic form and contract in the cathodic form and vice versa for films with high content of2, where anions and cations dominate counterion transport from solution, respectively.
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- Award ID(s):
- 1808286
- PAR ID:
- 10361213
- Publisher / Repository:
- The Electrochemical Society
- Date Published:
- Journal Name:
- Journal of The Electrochemical Society
- Volume:
- 167
- Issue:
- 16
- ISSN:
- 0013-4651
- Page Range / eLocation ID:
- Article No. 166511
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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