Abstract
MacEtch allows subwavelength-structured (SWS) texturing on the GaAs surface without compromising crystallinity. The current density increases greatly, which is directly due to the reduction in the reflectance. Photons absorbed under reduced light reflectance are less affected by the charge recombination arising from crystal defects. The catalytic metal remaining after MacEtch serves as a catalyst for water splitting and increases the open-circuit potentials of the SWS GaAs photocathodes. The SWS GaAs not only amplifies the absorption of light, but also improves the collection of deeply generated photons at long wavelengths. The solar-weighted reflectance (SWR) of SWS GaAs is 6.6%, which was much lower than the 39.0% of bare GaAs. The light-limited photocurrent density (LLPC) increased by approximately 90% and the tafel slope improved as etching progressed. The external quantum efficiency was as high as 80%, especially at long wavelengths, after MacEtch. SWS GaAs photocathodes fabricated using MacEtch significantly reduce reflectance and recombination loss, thereby improving the key performance of PEC for hydrogen production. This technology can fully utilize the high absorption rate and carrier mobility of GaAs and is applicable to various photoelectric conversion device performance enhancements.
| Original language | English |
|---|---|
| Pages (from-to) | 15367-15373 |
| Number of pages | 7 |
| Journal | Nanoscale |
| Volume | 11 |
| Issue number | 32 |
| DOIs | |
| Publication status | Published - 2019 Aug 28 |
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All Science Journal Classification (ASJC) codes
- Materials Science(all)
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Subwavelength photocathodes via metal-assisted chemical etching of GaAs for solar hydrogen generation. / Choi, Keorock; Kim, Kyunghwan; Moon, In Kyu; Bang, Jangwon; Oh, Jungwoo.
In: Nanoscale, Vol. 11, No. 32, 28.08.2019, p. 15367-15373.Research output: Contribution to journal › Article
TY - JOUR
T1 - Subwavelength photocathodes via metal-assisted chemical etching of GaAs for solar hydrogen generation
AU - Choi, Keorock
AU - Kim, Kyunghwan
AU - Moon, In Kyu
AU - Bang, Jangwon
AU - Oh, Jungwoo
PY - 2019/8/28
Y1 - 2019/8/28
N2 - MacEtch allows subwavelength-structured (SWS) texturing on the GaAs surface without compromising crystallinity. The current density increases greatly, which is directly due to the reduction in the reflectance. Photons absorbed under reduced light reflectance are less affected by the charge recombination arising from crystal defects. The catalytic metal remaining after MacEtch serves as a catalyst for water splitting and increases the open-circuit potentials of the SWS GaAs photocathodes. The SWS GaAs not only amplifies the absorption of light, but also improves the collection of deeply generated photons at long wavelengths. The solar-weighted reflectance (SWR) of SWS GaAs is 6.6%, which was much lower than the 39.0% of bare GaAs. The light-limited photocurrent density (LLPC) increased by approximately 90% and the tafel slope improved as etching progressed. The external quantum efficiency was as high as 80%, especially at long wavelengths, after MacEtch. SWS GaAs photocathodes fabricated using MacEtch significantly reduce reflectance and recombination loss, thereby improving the key performance of PEC for hydrogen production. This technology can fully utilize the high absorption rate and carrier mobility of GaAs and is applicable to various photoelectric conversion device performance enhancements.
AB - MacEtch allows subwavelength-structured (SWS) texturing on the GaAs surface without compromising crystallinity. The current density increases greatly, which is directly due to the reduction in the reflectance. Photons absorbed under reduced light reflectance are less affected by the charge recombination arising from crystal defects. The catalytic metal remaining after MacEtch serves as a catalyst for water splitting and increases the open-circuit potentials of the SWS GaAs photocathodes. The SWS GaAs not only amplifies the absorption of light, but also improves the collection of deeply generated photons at long wavelengths. The solar-weighted reflectance (SWR) of SWS GaAs is 6.6%, which was much lower than the 39.0% of bare GaAs. The light-limited photocurrent density (LLPC) increased by approximately 90% and the tafel slope improved as etching progressed. The external quantum efficiency was as high as 80%, especially at long wavelengths, after MacEtch. SWS GaAs photocathodes fabricated using MacEtch significantly reduce reflectance and recombination loss, thereby improving the key performance of PEC for hydrogen production. This technology can fully utilize the high absorption rate and carrier mobility of GaAs and is applicable to various photoelectric conversion device performance enhancements.
UR - http://www.scopus.com/inward/record.url?scp=85070785502&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85070785502&partnerID=8YFLogxK
U2 - 10.1039/c9nr03870a
DO - 10.1039/c9nr03870a
M3 - Article
C2 - 31389459
AN - SCOPUS:85070785502
VL - 11
SP - 15367
EP - 15373
JO - Nanoscale
JF - Nanoscale
SN - 2040-3364
IS - 32
ER -