论文标题
电解石墨烯场现场效应晶体管上泄漏电流的起源
Origins of leakage currents on electrolyte-gated graphene field-effect transistors
论文作者
论文摘要
石墨烯场效应晶体管被广泛用于生物传感器的开发。但是，尚未完全了解有关其功能细节的某些基本问题。这些问题之一是电解质门控配置中存在栅极（泄漏）电流。在这里，我们报告了考虑到这种化学蒸气沉积现象（CVD）种植石墨烯的原因的观察结果。我们观察到栅极电流反映了在电化学电池中工作电极 - 反电极对电流电极流相似的电流。当石墨烯通道被孔掺杂时，栅极电流是电容的，而在现场效应测量中被电子掺杂时。法拉达电流归因于溶解在水溶液中的氧气的减少，并且其幅度随着每次测量而增加。我们使用氧化还原探针FC（MEOH）2使用循环伏安法来表征造成这种激活的石墨烯结构的变化。总的来说，我们的结果表明，通过晶体管表面的催化氧气减少的过程，出现了更多的缺陷。
Graphene field-effect transistors are widely used for development of biosensors. However, certain fundamental questions about details of their functioning are not fully understood yet. One of these questions is the presence of gate (leakage) currents in the electrolyte-gated configuration. Here, we report our observations considering causes of this phenomena on chemical vapor deposition (CVD) grown graphene. We observed that gate currents reflect currents that occur on the transistor surface similarly to a working electrode - counter electrode pair currents in an electrochemical cell. Gate currents are capacitive when the graphene channel is doped by holes and Faradaic when it is doped by electrons in field-effect measurements. The Faradaic current is attributed to a reduction of oxygen dissolved in the aqueous solution and its magnitude increases with each measurement. We employed cyclic voltammetry with a redox probe Fc(MeOH)2 to characterize changes of the graphene structure that are responsible for this activation. Collectively, our results reveal that through the course of catalytic oxygen reduction on the transistor's surface more defects appear.
