Self-powered graphene transistor mimics synapses for wearable sensing

Researchers at Dongguk University in South Korea have developed a battery-free, flexible graphene transistor that mimics biological synapses and can recognize human activity without any external power source.

A self-powered graphene-channel transistor, driven entirely by triboelectric nanogenerators, mimics biological synaptic behavior and recognizes human activity from touch alone.

The device is a graphene-channel ion-gel-gated transistor (g-IGT), fabricated on a flexible PET substrate, with monolayer CVD graphene as the channel and an ion-gel electrolyte (based on the ionic liquid EMIM-TFSI) serving as the gate dielectric. Two triboelectric nanogenerators (TENGs), built from a poly(vinylidene fluoride-co-trifluoroethylene) triboelectric layer, are coupled to the transistor: one connected to the gate supplies pre-synaptic spikes, and one connected to the drain supplies post-synaptic spikes. As the TENGs undergo repeated contact and separation from touch or mechanical motion, they generate voltage pulses that drive ion migration within the gel and modulate the graphene channel’s conductance – reproducing synaptic signaling entirely from harvested mechanical energy, with no external power supply or battery.

A self-powered graphene-channel transistor, driven entirely by triboelectric nanogenerators, mimics biological synaptic behavior and recognizes human activity from touch alone.The device is a graphene-channel ion-gel-gated transistor (g-IGT), fabricated on a flexible PET substrate, with monolayer CVD graphene as the channel and an ion-gel electrolyte (based on the ionic liquid EMIM-TFSI) serving as the gate dielectric. Two triboelectric nanogenerators (TENGs), built from a poly(vinylidene fluoride-co-trifluoroethylene) triboelectric layer, are coupled to the transistor: one connected to the gate supplies pre-synaptic spikes, and one connected to the drain supplies post-synaptic spikes. As the TENGs undergo repeated contact and separation from touch or mechanical motion, they generate voltage pulses that drive ion migration within the gel and modulate the graphene channel’s conductance – reproducing synaptic signaling entirely from harvested mechanical energy, with no external power supply or battery.

Read More Graphene-Info – Graphene industry portal