High Ion/Ioff ratio of electrochemically prepared graphene quantum dots

Herein we report lithographically fabricated FET with annealed graphene quantum dots (GQDs) as channel shows higher Ion/Ioff ratio as compared to as-prepared GQDs as channel. GQDs are synthesized via an electrochemical avenue using multiwall carbon nanotubes. As-prepared dots of 4.5 ± 0.55 nm average diameter are found to be p-type in air under ambient conditions with Ion/Ioff ratio of 45 and after annealing in Argon atmosphere at 300°C for 20 min it shows ambipolar nature with significant increase in resistance with Ion/Ioff ratio of 200.