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arXiv · 1610.04379

Tungsten doping of Ta3N5-Nanotubes for Band Gap Narrowing and Enhanced Photoelectrochemical Water Splitting Efficiency

Sabina Grigorescu·Benedikt Baerhausen·Lei Wang·Anca Mazare·Jeong Eun Yoo·Robert Hahn·Patrik Schmuki
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Abstract

Ordered W-doped Ta2O5 nanotube arrays were grown by self-organizing electrochemical anodization of TaW alloys with different tungsten concentrations and by a suitable high temperature ammonia treatment, fully converted to W:Ta3N5 tubular structures. A main effect found is that W doping can decrease the band gap from 2 eV (bare Ta3N5) down to 1.75 eV. Ta3N5 nanotubes grown on 0.5 at% W alloy and modified with (CoOH)x as co-catalyst show ~33% higher photocurrents in photoelectrochemical (PEC) water splitting than pure Ta3N5.

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Sabina Grigorescu, Benedikt Baerhausen, Lei Wang, Anca Mazare, Jeong Eun Yoo, Robert Hahn, Patrik Schmuki. 2016-10-14. Tungsten doping of Ta3N5-Nanotubes for Band Gap Narrowing and Enhanced Photoelectrochemical Water Splitting Efficiency. https://doi.org/10.1016/j.elecom.2014.12.019

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