Time-Resolved Observations of Photo-Generated Charge-Carrier Dynamics in Sb2Se3 Photocathodes for Photoelectrochemical Water Splitting

Wooseok Yang, Seungmin Lee, Hyeok Chan Kwon, Jeiwan Tan, Hyungsoo Lee, Jaemin Park, Yunjung Oh, Hyunyong Choi, Jooho Moon

Research output: Contribution to journalArticle

20 Citations (Scopus)

Abstract

Solar-energy conversion by photoelectrochemical (PEC) devices is driven by the separation and transfer of photogenerated charge carriers. Thus, understanding carrier dynamics in a PEC device is essential to realizing efficient solar-energy conversion. Here, we investigate time-resolved carrier dynamics in emerging low-cost Sb2Se3 nanostructure photocathodes for PEC water splitting. Using terahertz spectroscopy, we observed an initial mobility loss within tens of picoseconds due to carrier localization and attributed the origin of carrier localization to the rich surface of Sb2Se3 nanostructures. In addition, a possible recombination at the interface between Sb2Se3 and the back contact is elucidated by time-resolved photoluminescence analysis. We also demonstrated the dual role of the RuOx co-catalyst in reducing surface recombination and enhancing charge transfer in full devices using intensity-modulated spectroscopy. The relatively low onset potential of the Sb2Se3 photocathode is attributed to the sluggish charge transfer at a low applied bias rather than to fast surface recombination. We believe that our insights on carrier dynamics would be an important step toward achieving highly efficient Sb2Se3 photocathodes.

Original languageEnglish
Pages (from-to)11088-11097
Number of pages10
JournalACS Nano
Volume12
Issue number11
DOIs
Publication statusPublished - 2018 Nov 27

Fingerprint

Photocathodes
water splitting
photocathodes
Charge carriers
charge carriers
Energy conversion
photoelectrochemical devices
Solar energy
Water
Charge transfer
Nanostructures
solar energy conversion
Terahertz spectroscopy
charge transfer
Photoluminescence
Spectroscopy
Catalysts
spectroscopy
emerging
Costs

All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Engineering(all)
  • Physics and Astronomy(all)

Cite this

Yang, Wooseok ; Lee, Seungmin ; Kwon, Hyeok Chan ; Tan, Jeiwan ; Lee, Hyungsoo ; Park, Jaemin ; Oh, Yunjung ; Choi, Hyunyong ; Moon, Jooho. / Time-Resolved Observations of Photo-Generated Charge-Carrier Dynamics in Sb2Se3 Photocathodes for Photoelectrochemical Water Splitting. In: ACS Nano. 2018 ; Vol. 12, No. 11. pp. 11088-11097.
@article{775538793ec3429fa9d45df6bbd13d93,
title = "Time-Resolved Observations of Photo-Generated Charge-Carrier Dynamics in Sb2Se3 Photocathodes for Photoelectrochemical Water Splitting",
abstract = "Solar-energy conversion by photoelectrochemical (PEC) devices is driven by the separation and transfer of photogenerated charge carriers. Thus, understanding carrier dynamics in a PEC device is essential to realizing efficient solar-energy conversion. Here, we investigate time-resolved carrier dynamics in emerging low-cost Sb2Se3 nanostructure photocathodes for PEC water splitting. Using terahertz spectroscopy, we observed an initial mobility loss within tens of picoseconds due to carrier localization and attributed the origin of carrier localization to the rich surface of Sb2Se3 nanostructures. In addition, a possible recombination at the interface between Sb2Se3 and the back contact is elucidated by time-resolved photoluminescence analysis. We also demonstrated the dual role of the RuOx co-catalyst in reducing surface recombination and enhancing charge transfer in full devices using intensity-modulated spectroscopy. The relatively low onset potential of the Sb2Se3 photocathode is attributed to the sluggish charge transfer at a low applied bias rather than to fast surface recombination. We believe that our insights on carrier dynamics would be an important step toward achieving highly efficient Sb2Se3 photocathodes.",
author = "Wooseok Yang and Seungmin Lee and Kwon, {Hyeok Chan} and Jeiwan Tan and Hyungsoo Lee and Jaemin Park and Yunjung Oh and Hyunyong Choi and Jooho Moon",
year = "2018",
month = "11",
day = "27",
doi = "10.1021/acsnano.8b05446",
language = "English",
volume = "12",
pages = "11088--11097",
journal = "ACS Nano",
issn = "1936-0851",
publisher = "American Chemical Society",
number = "11",

}

Time-Resolved Observations of Photo-Generated Charge-Carrier Dynamics in Sb2Se3 Photocathodes for Photoelectrochemical Water Splitting. / Yang, Wooseok; Lee, Seungmin; Kwon, Hyeok Chan; Tan, Jeiwan; Lee, Hyungsoo; Park, Jaemin; Oh, Yunjung; Choi, Hyunyong; Moon, Jooho.

In: ACS Nano, Vol. 12, No. 11, 27.11.2018, p. 11088-11097.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Time-Resolved Observations of Photo-Generated Charge-Carrier Dynamics in Sb2Se3 Photocathodes for Photoelectrochemical Water Splitting

AU - Yang, Wooseok

AU - Lee, Seungmin

AU - Kwon, Hyeok Chan

AU - Tan, Jeiwan

AU - Lee, Hyungsoo

AU - Park, Jaemin

AU - Oh, Yunjung

AU - Choi, Hyunyong

AU - Moon, Jooho

PY - 2018/11/27

Y1 - 2018/11/27

N2 - Solar-energy conversion by photoelectrochemical (PEC) devices is driven by the separation and transfer of photogenerated charge carriers. Thus, understanding carrier dynamics in a PEC device is essential to realizing efficient solar-energy conversion. Here, we investigate time-resolved carrier dynamics in emerging low-cost Sb2Se3 nanostructure photocathodes for PEC water splitting. Using terahertz spectroscopy, we observed an initial mobility loss within tens of picoseconds due to carrier localization and attributed the origin of carrier localization to the rich surface of Sb2Se3 nanostructures. In addition, a possible recombination at the interface between Sb2Se3 and the back contact is elucidated by time-resolved photoluminescence analysis. We also demonstrated the dual role of the RuOx co-catalyst in reducing surface recombination and enhancing charge transfer in full devices using intensity-modulated spectroscopy. The relatively low onset potential of the Sb2Se3 photocathode is attributed to the sluggish charge transfer at a low applied bias rather than to fast surface recombination. We believe that our insights on carrier dynamics would be an important step toward achieving highly efficient Sb2Se3 photocathodes.

AB - Solar-energy conversion by photoelectrochemical (PEC) devices is driven by the separation and transfer of photogenerated charge carriers. Thus, understanding carrier dynamics in a PEC device is essential to realizing efficient solar-energy conversion. Here, we investigate time-resolved carrier dynamics in emerging low-cost Sb2Se3 nanostructure photocathodes for PEC water splitting. Using terahertz spectroscopy, we observed an initial mobility loss within tens of picoseconds due to carrier localization and attributed the origin of carrier localization to the rich surface of Sb2Se3 nanostructures. In addition, a possible recombination at the interface between Sb2Se3 and the back contact is elucidated by time-resolved photoluminescence analysis. We also demonstrated the dual role of the RuOx co-catalyst in reducing surface recombination and enhancing charge transfer in full devices using intensity-modulated spectroscopy. The relatively low onset potential of the Sb2Se3 photocathode is attributed to the sluggish charge transfer at a low applied bias rather than to fast surface recombination. We believe that our insights on carrier dynamics would be an important step toward achieving highly efficient Sb2Se3 photocathodes.

UR - http://www.scopus.com/inward/record.url?scp=85056792888&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85056792888&partnerID=8YFLogxK

U2 - 10.1021/acsnano.8b05446

DO - 10.1021/acsnano.8b05446

M3 - Article

C2 - 30358980

AN - SCOPUS:85056792888

VL - 12

SP - 11088

EP - 11097

JO - ACS Nano

JF - ACS Nano

SN - 1936-0851

IS - 11

ER -