Abstract
Nanostructured black Si materials prepared by metal-assisted wet chemical etching (MaCE) using HF to drive the nanostructuring, have emerged as excellent light-harvesting materials for solar water splitting. Recently, their remarkable solar-to-hydrogen conversion capability was attributed to their surface oxidation mechanism. However, the same mechanism inhibits the interfacial kinetics within hours, and therefore they are deemed not suitable for a fully-functional hydrogen generating cell. Herein, we investigate the performance and interfacial kinetics of solar-to-hydrogen fuel conversion on black Si photocathodes that, for the first time, are free of any metal catalysts. We developed a near 100% metal-free Si interface by a HF-free etching approach. Systematic analysis and optimization of the nanostructure morphology and photoelectrochemical procedures supported continuous photoelectrochemical hydrogen generation for ∼250 h, involving −1.18 × 104 C.cm−2 of charge transfer at overpotentials as low as −0.2 V vs. RHE. We find that this high-performance of bSi makes it attractive as a green solar-to-hydrogen platform.
| Original language | English |
|---|---|
| Pages (from-to) | 453-462 |
| Number of pages | 10 |
| Journal | Electrochimica Acta |
| Volume | 235 |
| DOIs | |
| Publication status | Published - 1 May 2017 |
Keywords
- Black silicon
- Metal-free
- Oxidized black Si
- Photocathodes
- SiNW catalysts
Cite this
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Metal-free black silicon for solar-powered hydrogen generation. / Halima, Ahmed F.; Zhang, Xinyi; MacFarlane, Douglas R.
In: Electrochimica Acta, Vol. 235, 01.05.2017, p. 453-462.Research output: Contribution to journal › Article › Research › peer-review
TY - JOUR
T1 - Metal-free black silicon for solar-powered hydrogen generation
AU - Halima, Ahmed F.
AU - Zhang, Xinyi
AU - MacFarlane, Douglas R.
PY - 2017/5/1
Y1 - 2017/5/1
N2 - Nanostructured black Si materials prepared by metal-assisted wet chemical etching (MaCE) using HF to drive the nanostructuring, have emerged as excellent light-harvesting materials for solar water splitting. Recently, their remarkable solar-to-hydrogen conversion capability was attributed to their surface oxidation mechanism. However, the same mechanism inhibits the interfacial kinetics within hours, and therefore they are deemed not suitable for a fully-functional hydrogen generating cell. Herein, we investigate the performance and interfacial kinetics of solar-to-hydrogen fuel conversion on black Si photocathodes that, for the first time, are free of any metal catalysts. We developed a near 100% metal-free Si interface by a HF-free etching approach. Systematic analysis and optimization of the nanostructure morphology and photoelectrochemical procedures supported continuous photoelectrochemical hydrogen generation for ∼250 h, involving −1.18 × 104 C.cm−2 of charge transfer at overpotentials as low as −0.2 V vs. RHE. We find that this high-performance of bSi makes it attractive as a green solar-to-hydrogen platform.
AB - Nanostructured black Si materials prepared by metal-assisted wet chemical etching (MaCE) using HF to drive the nanostructuring, have emerged as excellent light-harvesting materials for solar water splitting. Recently, their remarkable solar-to-hydrogen conversion capability was attributed to their surface oxidation mechanism. However, the same mechanism inhibits the interfacial kinetics within hours, and therefore they are deemed not suitable for a fully-functional hydrogen generating cell. Herein, we investigate the performance and interfacial kinetics of solar-to-hydrogen fuel conversion on black Si photocathodes that, for the first time, are free of any metal catalysts. We developed a near 100% metal-free Si interface by a HF-free etching approach. Systematic analysis and optimization of the nanostructure morphology and photoelectrochemical procedures supported continuous photoelectrochemical hydrogen generation for ∼250 h, involving −1.18 × 104 C.cm−2 of charge transfer at overpotentials as low as −0.2 V vs. RHE. We find that this high-performance of bSi makes it attractive as a green solar-to-hydrogen platform.
KW - Black silicon
KW - Metal-free
KW - Oxidized black Si
KW - Photocathodes
KW - SiNW catalysts
UR - http://www.scopus.com/inward/record.url?scp=85016072504&partnerID=8YFLogxK
U2 - 10.1016/j.electacta.2017.03.086
DO - 10.1016/j.electacta.2017.03.086
M3 - Article
VL - 235
SP - 453
EP - 462
JO - Electrochimica Acta
JF - Electrochimica Acta
SN - 0013-4686
ER -