title: Multi-resistive reduced graphene oxide diode with reversible surface electrochemical reaction induced carrier control.
abstract: The extended application of graphene-based electronic devices requires a bandgap opening in order to realize the targeted device functionality. Since the bandgap tuning of pristine graphene is limited to 360 meV, the chemical modification of graphene is considered essential to achieve a large bandgap opening at the expense of electrical properties degradation. Reduced graphene oxide (RGO) has attracted significant interest for fabricating graphene-based semiconductors since it has several advantages over other forms of chemically modified graphene; such as tunable bandgap opening, decent electrical properties, and easy synthesis. Because of the reduced bonding nature of RGO, the role of metastable oxygen in the RGO matrix is recently highlighted and it may offer emerging ionic devices. In this study, we show that multi-resistivity RGO/n-Si diodes can be obtained by controlling the RGO thickness at a nanometer scale. This is made possible by (1) a metastable lattice-oxygen drift within bulk RGO and (2) electrochemical ambient hydroxyl (OH) formation at the RGO surface. The effect demonstrated in a p-RGO/n-Si heterojunction diode is equivalent to electrochemically driven reversible electronic manipulation and therefore provides an important basis for the application of O bistability in RGO for chemical sensors and electrocatalysis.
authors.affiliation: 1] Department of Energy Systems Research, Ajou University, Suwon 443-739, Republic of Korea [2] Department of Materials Science and Engineering, Ajou University, Suwon 443-739, Republic of Korea.
authors.forename: Hyungtak
authors.initials: H
authors.lastname: Seo
authors.affiliation: Department of Environmental Engineering, Inha University, 100 Inha- ro, Nam-gu, Incheon, 402-751, Republic of Korea.
authors.forename: Seungbae
authors.initials: S
authors.lastname: Ahn
authors.affiliation: 1] Department of Energy Systems Research, Ajou University, Suwon 443-739, Republic of Korea [2] Department of Materials Science and Engineering, Ajou University, Suwon 443-739, Republic of Korea.
authors.forename: Jinseo
authors.initials: J
authors.lastname: Kim
authors.affiliation: 1] Department of Energy Systems Research, Ajou University, Suwon 443-739, Republic of Korea [2] Department of Materials Science and Engineering, Ajou University, Suwon 443-739, Republic of Korea.
authors.forename: Young-Ahn
authors.initials: YA
authors.lastname: Lee
authors.affiliation: School of Mechanical Engineering, University of Ulsan, Ulsan 680-749, Republic of Korea.
authors.forename: Koo-Hyun
authors.initials: KH
authors.lastname: Chung
authors.affiliation: Department of Environmental Engineering, Inha University, 100 Inha- ro, Nam-gu, Incheon, 402-751, Republic of Korea.
authors.forename: Ki-Joon
authors.initials: KJ
authors.lastname: Jeon