Methyl Methacrylate Copolymer with Pendant Thioxanthenone Groups as Active Layer for Resistive Memory Devices

An electro‐active copolymer of methyl methacrylate and 2‐((4‐acroylpiperazine‐1‐yl)methyl)‐9H‐thioxanthene‐9‐one (poly(MMA‐co‐ThS)) was synthesized by radical polymerization. The copolymer has good solubility in most organic solvents, thermal stability up to 282 °C and excellent ability to form thin...

Full description

Saved in:

Bibliographic Details
Published in:	Chemphyschem Vol. 25; no. 21; pp. e202400266 - n/a
Main Authors:	Odintsov, Danila S., Gismatulin, Andrei A., Shundrina, Inna K., Buktoyarova, Alexandra D., Os'kina, Irina A., Beckmann, Jens, Azarov, Ivan A., Dementeva, Ekaterina V., Shundrin, Leonid A., Gritsenko, Vladimir A.
Format:	Journal Article
Language:	English
Published:	Germany Wiley Subscription Services, Inc 04-11-2024
Subjects:	Absorption spectra Aluminum Charge transport Copolymers Current voltage characteristics Electrochromism Memory devices Memristor Optical transition Organic polymers Pendant groups Polymethyl methacrylate Silicon Silicon wafers Spectroelectrochemistry Thermal stability Thin films Thioxanthenone Memristor Charge transport Organic polymers Pendant groups Spectroelectrochemistry
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	An electro‐active copolymer of methyl methacrylate and 2‐((4‐acroylpiperazine‐1‐yl)methyl)‐9H‐thioxanthene‐9‐one (poly(MMA‐co‐ThS)) was synthesized by radical polymerization. The copolymer has good solubility in most organic solvents, thermal stability up to 282 °C and excellent ability to form thin films on silicon wafers. Poly(MMA‐co‐ThS) films exhibited an electrochemical and electrochromic activity resulting in the formation of long‐lived radical anion states of pendant thioxanthone groups inside the film. These states exhibit optical transitions in the visible region as a broad optical absorption band, 500<λ<900 nm (1.38<Wopt(ThS)<2.48 eV) with a maximum at λmax=675 nm (1.84 eV). Using temperature measurements of the current–voltage characteristics of p‐Si(100)/poly(MMA‐co‐ThS)/Al devices, it was shown that the charge transport in the film occurs by a multiphonon mechanism, which is quantitatively described by the Nasyrov–Gritsenko model of phonon‐assisted tunneling between traps. The value of the optical transition energy of the trap, determined by the Nasyrov–Gritsenko model, Wopt=1.8 eV, is in a good agreement with Wopt(ThS), confirming the nature of the traps as 9H‐thioxanthen‐9‐one structures. The n++Si(100)/poly(MMA‐co‐ThS)/Al memory device exhibited a memristive effect (reversible ON/OFF switching of the device) with an initial “forming” cycle followed by repetitive memory cycles characterized by bipolar switching. A methyl methacrylate copolymer containing electron‐withdrawing 9H‐thioxanthen‐9‐one pendant groups in its structure (poly(MMA‐co‐ThS)) was synthesized by radical polymerization. Using temperature measurements of the current–voltage characteristics of the p‐Si(100)/poly(MMA‐co‐ThS)/Al model memory device, it was shown that the charge transport in the copolymer film is well described by the Nasyrov–Gritsenko model of phonon‐assisted tunneling between traps. For the first time, the nature of the electron traps as thioxanthenone pendant groups was identified using a combination of spectroelectrochemical and electrophysical measurements.
Bibliography:	ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23
ISSN:	1439-4235 1439-7641 1439-7641
DOI:	10.1002/cphc.202400266