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Single-crystalline, wormlike hematite photoanodes for efficient solar water splitting.

ABSTRACT: A hematite photoanode showing a stable, record-breaking performance of 4.32?mA/cm² photoelectrochemical water oxidation current at 1.23?V vs. RHE under simulated 1-sun (100?mW/cm²) irradiation is reported. This photocurrent corresponds to ca. 34% of the maximum theoretical limit expected for hematite with a band gap of 2.1?V. The photoanode produced stoichiometric hydrogen and oxygen gases in amounts close to the expected values from the photocurrent. The hematitle has a unique single-crystalline "wormlike" morphology produced by in-situ two-step annealing at 550°C and 800°C of ?-FeOOH nanorods grown directly on a transparent conducting oxide glass via an all-solution method. In addition, it is modified by platinum doping to improve the charge transfer characteristics of hematite and an oxygen-evolving co-catalyst on the surface.

SUBMITTER: Kim JY

PROVIDER: S-EPMC3775410 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Single-crystalline, wormlike hematite photoanodes for efficient solar water splitting.

Kim Jae Young JY Magesh Ganesan G Youn Duck Hyun DH Jang Ji-Wook JW Kubota Jun J Domen Kazunari K Lee Jae Sung JS

Scientific reports 20130101

A hematite photoanode showing a stable, record-breaking performance of 4.32 mA/cm² photoelectrochemical water oxidation current at 1.23 V vs. RHE under simulated 1-sun (100 mW/cm²) irradiation is reported. This photocurrent corresponds to ca. 34% of the maximum theoretical limit expected for hematite with a band gap of 2.1 V. The photoanode produced stoichiometric hydrogen and oxygen gases in amounts close to the expected values from the photocurrent. The hematitle has a unique single-crystallin ...[more]

PMID: 24045290

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