Embedding Azobenzol-Decorated Tetraphenylethylene into the Polymer Matrix to Implement a Ternary Memory Device with High Working Temperature/Humidity

The
development of new high-density memories that can work in harsh
environments such as high temperature and humidity will be significant
for some special occasions such as oil and geothermal industries.
Herein, a facial strategy for implementing a ternary memory device
with high working temperature/humidity was executed. In detail, an
asymmetric aggregation-induced-emission active molecule (azobenzol-decorated
tetraphenylethylene, i.e., TPE-Azo) was embedded into flexible poly­(ethylene-alt-maleic anhydride) (PEM) to prepare a TPE-Azo@PEM composite,
which served as an active layer to fabricate the FTO/TPE-Azo@PEM/Ag
device. This device can demonstrate excellent ternary memory performances
with a current ratio of 1:104.2:101.6 for “OFF”,
“ON1”, and “ON2” states. Specially, it
can exhibit good environmental endurance at high working temperature
(350 °C) and humidity (RH = 90%). The ternary memory mechanism
can be explained as the combination of aggregation-induced current/conductance
and conformational change-induced charge transfer in the TPE-Azo molecule,
which was verified by Kelvin probe force microscopy, UV–vis
spectra, X-ray diffraction, and single-crystal structural analysis.
This strategy can be used as a universal method for the construction
of high-density multilevel memristors with good environmental tolerance.