Photoelectrochemical hydrogen evolution using Si microwire arrays.
نویسندگان
چکیده
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.
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ورودعنوان ژورنال:
- Journal of the American Chemical Society
دوره 133 5 شماره
صفحات -
تاریخ انتشار 2011