TY - JOUR
T1 - Enhancement of Charge Separation and Hydrogen Evolution on Particulate La5Ti2CuS5O7 Photocathodes by Surface Modification
AU - Liu, Jingyuan
AU - Hisatomi, Takashi
AU - Murthy, Dharmapura H.K.
AU - Zhong, Miao
AU - Nakabayashi, Mamiko
AU - Higashi, Tomohiro
AU - Suzuki, Yohichi
AU - Matsuzaki, Hiroyuki
AU - Seki, Kazuhiko
AU - Furube, Akihiro
AU - Shibata, Naoya
AU - Katayama, Masao
AU - Minegishi, Tsutomu
AU - Domen, Kazunari
N1 - Funding Information:
This work was financially supported by Grants-in-Aids for Scientific Research (A) (No. 16H02417), for Young Scientists (A) (No. 15H05494), and for Young Scientists (B) (No. 15K17895) from the Japan Society for the Promotion of Science (JSPS), by the Artificial Photosynthesis Project of the New Energy and Industrial Technology Development Organization (NEDO), and by the Companhia Brasileira de Mmetallurgia e Mineração (CBMM). Part of this work was conducted at the Advanced Characterization Nanotechnology Platform at the University of Tokyo, supported by the Nanotechnology Platform of the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan. The authors also wish to thank Mr. Atsushi Furuki of the University of Tokyo for his assistance in preparing the Mg-LTC powder. One of the authors (J.L.) gratefully acknowledges the support of a Japan Chemical Industry Association (JCIA) Fellowship.
Publisher Copyright:
© 2016 American Chemical Society.
PY - 2017/1/19
Y1 - 2017/1/19
N2 - Particulate La5Ti2CuS5O7 (LTC) photocathodes prepared by particle transfer show a positive onset potential of 0.9 V vs RHE for the photocathodic current in photoelectrochemical (PEC) H2 evolution. However, the low photocathodic current imposes a ceiling on the solar-to-hydrogen energy conversion efficiency of PEC cells based on LTC photocathodes. To improve the photocurrent, in this work, the surface of Mg-doped LTC photocathodes was modified with TiO2, Nb2O5, and Ta2O5 by radio frequency reactive magnetron sputtering. The photocurrent of the modified Mg-doped LTC photocathodes was doubled because these oxides formed type-II heterojunctions and extended the lifetimes of photogenerated charge carriers. The enhanced photocathodic current was attributed to hydrogen evolution at a positive potential of +0.7 V vs RHE. This work opens up possibilities for improving PEC hydrogen evolution on particulate photocathodes based on surface oxide modifications and also highlights the importance of the band gap alignment.
AB - Particulate La5Ti2CuS5O7 (LTC) photocathodes prepared by particle transfer show a positive onset potential of 0.9 V vs RHE for the photocathodic current in photoelectrochemical (PEC) H2 evolution. However, the low photocathodic current imposes a ceiling on the solar-to-hydrogen energy conversion efficiency of PEC cells based on LTC photocathodes. To improve the photocurrent, in this work, the surface of Mg-doped LTC photocathodes was modified with TiO2, Nb2O5, and Ta2O5 by radio frequency reactive magnetron sputtering. The photocurrent of the modified Mg-doped LTC photocathodes was doubled because these oxides formed type-II heterojunctions and extended the lifetimes of photogenerated charge carriers. The enhanced photocathodic current was attributed to hydrogen evolution at a positive potential of +0.7 V vs RHE. This work opens up possibilities for improving PEC hydrogen evolution on particulate photocathodes based on surface oxide modifications and also highlights the importance of the band gap alignment.
UR - https://www.scopus.com/pages/publications/85017604419
UR - https://www.scopus.com/pages/publications/85017604419#tab=citedBy
U2 - 10.1021/acs.jpclett.6b02735
DO - 10.1021/acs.jpclett.6b02735
M3 - Article
C2 - 28033010
AN - SCOPUS:85017604419
SN - 1948-7185
VL - 8
SP - 375
EP - 379
JO - Journal of Physical Chemistry Letters
JF - Journal of Physical Chemistry Letters
IS - 2
ER -