Understanding asymmetric switching times in accumulation mode organic electrochemical transistors.
Nat Mater
; 23(5): 656-663, 2024 May.
Article
in En
| MEDLINE
| ID: mdl-38632374
ABSTRACT
Understanding the factors underpinning device switching times is crucial for the implementation of organic electrochemical transistors in neuromorphic computing, bioelectronics and real-time sensing applications. Existing models of device operation cannot explain the experimental observations that turn-off times are generally much faster than turn-on times in accumulation mode organic electrochemical transistors. Here, using operando optical microscopy, we image the local doping level of the transistor channel and show that turn-on occurs in two stages-propagation of a doping front, followed by uniform doping-while turn-off occurs in one stage. We attribute the faster turn-off to a combination of engineering as well as physical and chemical factors including channel geometry, differences in doping and dedoping kinetics and the phenomena of carrier-density-dependent mobility. We show that ion transport limits the operation speed in our devices. Our study provides insights into the kinetics of organic electrochemical transistors and guidelines for engineering faster organic electrochemical transistors.
Full text:
1
Database:
MEDLINE
Language:
En
Journal:
Nat Mater
Journal subject:
CIENCIA
/
QUIMICA
Year:
2024
Type:
Article
Affiliation country:
United States