title: Photoelectrochemical hydrogen evolution using Si microwire arrays.
abstract: Arrays of B-doped p-Si microwires, diffusion-doped with P to form a radial n(+) emitter and subsequently coated with a 1.5-nm-thick discontinuous film of evaporated Pt, were used as photocathodes for H(2) evolution from water. These electrodes yielded thermodynamically based energy-conversion efficiencies >5% under 1 sun solar simulation, despite absorbing less than 50% of the above-band-gap incident photons. Analogous p-Si wire-array electrodes yielded efficiencies <0.2%, largely limited by the low photovoltage generated at the p-Si/H(2)O junction.
authors.affiliation: California Institute of Technology, Pasadena, California 91125, United States.
authors.forename: Shannon W
authors.initials: SW
authors.lastname: Boettcher
authors.forename: Emily L
authors.initials: EL
authors.lastname: Warren
authors.forename: Morgan C
authors.initials: MC
authors.lastname: Putnam
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Santori
authors.forename: Daniel
authors.initials: D
authors.lastname: Turner-Evans
authors.forename: Michael D
authors.initials: MD
authors.lastname: Kelzenberg
authors.forename: Michael G
authors.initials: MG
authors.lastname: Walter
authors.forename: James R
authors.initials: JR
authors.lastname: McKone
authors.forename: Bruce S
authors.initials: BS
authors.lastname: Brunschwig
authors.forename: Harry A
authors.initials: HA
authors.lastname: Atwater
authors.forename: Nathan S
authors.initials: NS
authors.lastname: Lewis