| 초록 |
We demonstrated, for the first time, the salt–assisted poly(styrenesulfonic acid) (PSSH) proton conductor for gating graphene transistors. Upon applying gate bias, electric double layers (EDLs) were formed at both gate-proton conductor and proton conductor-graphene interfaces. The exceptionally high specific capacitance of the proton conductor yielded a high on–current and low voltage operation below 2 V of the graphene transistors. The electrical properties of the proton conductor-gated graphene transistors were enhanced dramatically by the optimization of i) the addition of the sodium halide salts (NaF, NaCl, NaBr, and NaI), ii) salt concentration, and iii) relative humidity. The resulting graphene transistors gated with on the PSSH containing NaI (0.5 M) exhibited hole and electron mobilities of 1394 and 712 cm2/Vs, respectively, at a drain bias of –0.05 V with almost zero Dirac voltage. The cut-off frequency of the device reached up to 100 kHz under RH 40%. The results presented represent a significant step in the application of graphene to low-power printed electronics. |
