Redox Active Binary Logic Gate Circuit for Homeland Security

Bipolar
junction transistors are at the frontiers of modern electronics
owing to their discrete voltage regulated operational levels. Here
we report a redox active binary logic gate (RLG) which can store a
“0” and “1” with distinct operational
levels, albeit without an external voltage stimuli. In the RLG, a
shorted configuration of half-cell electrodes provided the logic low
level and decoupled configuration relaxed the system to the logic
high level due to self-charge injection into the redox active polymeric
system. Galvanostatic intermittent titration and electrochemical quartz
crystal microbalance studies indicate the kinetics of self-charge
injection are quite faster and sustainable in polypyrrole based RLG,
recovering more than 70% signal in just 14 s with minor signal reduction
at the end of 10000 cycles. These remarkable properties of RLGs are
extended to design a security sensor which can detect and count intruders
in a locality with decent precision and switching speed.