title: Field-induced water electrolysis switches an oxide semiconductor from an insulator to a metal.
abstract: Water is composed of two strong electrochemically active agents, H(+) and OH(-) ions, but has not been used as an active electronic material in oxide semiconductors. In this study, we demonstrate that water-infiltrated nanoporous glass electrically switches an oxide semiconductor from insulator to metal. We fabricated a field-effect transistor structure on an oxide semiconductor, SrTiO(3), using water-infiltrated nanoporous glass-amorphous 12CaO·7Al(2)O(3)-as the gate insulator. Positive gate voltage, electron accumulation, water electrolysis and electrochemical reduction occur successively on the SrTiO(3) surface at room temperature. This leads to the formation of a thin (~3 nm) metal layer with an extremely high electron concentration (10(15)-10(16) cm(-2)), which exhibits exotic thermoelectric behaviour. The electron activity of water as it infiltrates nanoporous glass may find many useful applications in electronics or in energy storage.
authors.affiliation: 1] Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8603, Japan. [2] PRESTO, Japan Science and Technology Agency, 5 Sanbancho, Chiyoda, Tokyo 102-0075, Japan.
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Ohta
authors.forename: Yukio
authors.initials: Y
authors.lastname: Sato
authors.forename: Takeharu
authors.initials: T
authors.lastname: Kato
authors.forename: Sungwng
authors.initials: S
authors.lastname: Kim
authors.forename: Kenji
authors.initials: K
authors.lastname: Nomura
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Ikuhara
authors.forename: Hideo
authors.initials: H
authors.lastname: Hosono