title: Efficient generation of H2 by splitting water with an isothermal redox cycle.
abstract: Solar thermal water-splitting (STWS) cycles have long been recognized as a desirable means of generating hydrogen gas (H2) from water and sunlight. Two-step, metal oxide-based STWS cycles generate H2 by sequential high-temperature reduction and water reoxidation of a metal oxide. The temperature swings between reduction and oxidation steps long thought necessary for STWS have stifled STWS's overall efficiency because of thermal and time losses that occur during the frequent heating and cooling of the metal oxide. We show that these temperature swings are unnecessary and that isothermal water splitting (ITWS) at 1350°C using the "hercynite cycle" exhibits H2 production capacity >3 and >12 times that of hercynite and ceria, respectively, per mass of active material when reduced at 1350°C and reoxidized at 1000°C.
authors.affiliation: Department of Chemical and Biological Engineering, University of Colorado, Boulder, CO 80303, USA.
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Muhich
authors.forename: Brian W
authors.initials: BW
authors.lastname: Evanko
authors.forename: Kayla C
authors.initials: KC
authors.lastname: Weston
authors.forename: Paul
authors.initials: P
authors.lastname: Lichty
authors.forename: Xinhua
authors.initials: X
authors.lastname: Liang
authors.forename: Janna
authors.initials: J
authors.lastname: Martinek
authors.forename: Charles B
authors.initials: CB
authors.lastname: Musgrave
authors.forename: Alan W
authors.initials: AW
authors.lastname: Weimer