TY - JOUR
T1 - New Insights into the Electron-Collection Efficiency Improvement of CdS-Sensitized TiO 2 Nanorod Photoelectrodes by Interfacial Seed-Layer Mediation
AU - Chen, Yu Lin
AU - Chen, Yu Hung
AU - Chen, Jie Wen
AU - Cao, Fengren
AU - Li, Liang
AU - Luo, Zheng Ming
AU - Leu, Ing Chi
AU - Pu, Ying Chih
N1 - Funding Information:
Y.-C.P. acknowledges the financial support from the Ministry of Science and Technology of Taiwan (MOST) under grants MOST-104-2113-M-024-002-MY2, MOST-104-2738-M-024-001, and MOST-106-2113-M-024-002. I.-C.L. acknowledges the financial support from MOST under grant MOST 106-2221-E-024-007-MY2. L.L. acknowledges the support from the National Natural Science Foundation of China (51772197), 1000 Youth Talents Plan, and Key University Science Research Project of Jiangsu Province (17KJA430013).
Funding Information:
Y.-C.P. acknowledges the financial support from the Ministry of Science and Technology of Taiwan (MOST) under grants MOST-104-2113-M-024-002-MY2, MOST-104-2738-M-024-001, and MOST-106-2113-M-024-002.
Publisher Copyright:
© 2019 American Chemical Society.
PY - 2019/2/27
Y1 - 2019/2/27
N2 - Titanium dioxide (TiO 2 ) nanorods (NRs) are widely used as photoanodes in photoelectrochemical (PEC) solar fuel production because of their remarkable photoactivity and stability. In addition, TiO 2 NR electrode materials can be decorated with active CdS quantum dots (QDs) to expand the sunlight photon capture. The overall photoelectric conversion efficiency for TiO 2 NR or QD-sensitized TiO 2 NR electrode materials in PEC is typically dominated by their interfacial electron transfer (ET) properties. To understand the key factors affecting the ET, the anatase TiO 2 seed layer was added into the interface between the rutile TiO 2 NRs and fluorine-doped tin oxide (FTO) substrate. This seed layer enhanced the photocatalytic performance of both the TiO 2 NR and CdS QD-sensitized TiO 2 NR photoanodes in PEC. Time-resolved photoluminescence spectroscopy and PEC analyses, including Mott-Schottky, electrochemical impedance spectroscopy, and photovoltage (V ph ) measurements, were used to study the charge-carrier dynamics at the interfaces between the FTO, TiO 2 , and CdS QD. Analysis of the results showed that band alignment at the anatase/rutile junction between the TiO 2 and FTO promoted electron-collection efficiency (e EC ) at the FTO/TiO 2 interface and ET rate constant (k ET ) at the TiO 2 /CdS QD interface. Furthermore, 34% enhancement of the efficiency in hydrogen (H 2 ) generation demonstrated the potential of the TiO 2 seed-layer-mediated TiO 2 /CdS QD NR photoanode in the application of PEC solar fuel production. The current work represents new insights into the mechanism of ET in TiO 2 and TiO 2 /CdS QD NR, which is very useful for the development of photoelectrode materials in solar energy conversions.
AB - Titanium dioxide (TiO 2 ) nanorods (NRs) are widely used as photoanodes in photoelectrochemical (PEC) solar fuel production because of their remarkable photoactivity and stability. In addition, TiO 2 NR electrode materials can be decorated with active CdS quantum dots (QDs) to expand the sunlight photon capture. The overall photoelectric conversion efficiency for TiO 2 NR or QD-sensitized TiO 2 NR electrode materials in PEC is typically dominated by their interfacial electron transfer (ET) properties. To understand the key factors affecting the ET, the anatase TiO 2 seed layer was added into the interface between the rutile TiO 2 NRs and fluorine-doped tin oxide (FTO) substrate. This seed layer enhanced the photocatalytic performance of both the TiO 2 NR and CdS QD-sensitized TiO 2 NR photoanodes in PEC. Time-resolved photoluminescence spectroscopy and PEC analyses, including Mott-Schottky, electrochemical impedance spectroscopy, and photovoltage (V ph ) measurements, were used to study the charge-carrier dynamics at the interfaces between the FTO, TiO 2 , and CdS QD. Analysis of the results showed that band alignment at the anatase/rutile junction between the TiO 2 and FTO promoted electron-collection efficiency (e EC ) at the FTO/TiO 2 interface and ET rate constant (k ET ) at the TiO 2 /CdS QD interface. Furthermore, 34% enhancement of the efficiency in hydrogen (H 2 ) generation demonstrated the potential of the TiO 2 seed-layer-mediated TiO 2 /CdS QD NR photoanode in the application of PEC solar fuel production. The current work represents new insights into the mechanism of ET in TiO 2 and TiO 2 /CdS QD NR, which is very useful for the development of photoelectrode materials in solar energy conversions.
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U2 - 10.1021/acsami.8b22418
DO - 10.1021/acsami.8b22418
M3 - Article
C2 - 30726054
AN - SCOPUS:85062330954
SN - 1944-8244
VL - 11
SP - 8126
EP - 8137
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
IS - 8
ER -