TY - JOUR
T1 - Fe/Ru Oxide as a Versatile and Effective Cocatalyst for Boosting Z-Scheme Water-Splitting
T2 - Suppressing Undesirable Backward Electron Transfer
AU - Nakada, Akinobu
AU - Suzuki, Hajime
AU - Vequizo, Junie Jhon M.
AU - Ogawa, Kanta
AU - Higashi, Masanobu
AU - Saeki, Akinori
AU - Yamakata, Akira
AU - Kageyama, Hiroshi
AU - Abe, Ryu
N1 - Funding Information:
This work was supported by the CREST (JPMJCR1421), JSPS KAKENHI (JP17H06439, JP16H06439, JP16H06441, and JP15H03849), and JSPS Core-to-Core Program (A) Advanced Research Networks. The authors are also indebted to the technical division of Institute for Catalysis, Hokkaido University, for their help in building the experimental equipment.
Publisher Copyright:
© 2019 American Chemical Society.
PY - 2019/12/11
Y1 - 2019/12/11
N2 - The atificial Z-scheme is a promising and rational strategy for solar-to-chemical energy conversion such as water-splitting. In the Z-scheme, backward redox processes are an essential drawback that should be overcome to increase its efficiency. Here, we demonstrate that the simple co-loading of Fe/Ru oxide, (Fe,Ru)Ox, onto various photocatalysts effectively improves the efficiency of water oxidation by suppressing the undesirable backward oxidation of the redox reagent Fe2+. The (Fe,Ru)Ox co-loading on Bi4TaO8Cl afforded the highest water-splitting activity (apparent quantum efficiency of 1.6% at 420 nm) among the Z-scheme systems employing mixed-anion compounds as O2-evolving photocatalysts. The results of photoelectrochemical and electrochemical measurements along with time-resolved spectroscopy clarified the key roles of Fe/Ru oxide; the Ru oxide component functions as a "collector" of photogenerated carriers and active sites for surface redox reactions, while the Fe oxide component acts as a "blocker" against unfavorable Fe2+ oxidation. The versatile availability of Fe/Ru oxide has been demonstrated for other visible-light-responsive photocatalysts.
AB - The atificial Z-scheme is a promising and rational strategy for solar-to-chemical energy conversion such as water-splitting. In the Z-scheme, backward redox processes are an essential drawback that should be overcome to increase its efficiency. Here, we demonstrate that the simple co-loading of Fe/Ru oxide, (Fe,Ru)Ox, onto various photocatalysts effectively improves the efficiency of water oxidation by suppressing the undesirable backward oxidation of the redox reagent Fe2+. The (Fe,Ru)Ox co-loading on Bi4TaO8Cl afforded the highest water-splitting activity (apparent quantum efficiency of 1.6% at 420 nm) among the Z-scheme systems employing mixed-anion compounds as O2-evolving photocatalysts. The results of photoelectrochemical and electrochemical measurements along with time-resolved spectroscopy clarified the key roles of Fe/Ru oxide; the Ru oxide component functions as a "collector" of photogenerated carriers and active sites for surface redox reactions, while the Fe oxide component acts as a "blocker" against unfavorable Fe2+ oxidation. The versatile availability of Fe/Ru oxide has been demonstrated for other visible-light-responsive photocatalysts.
KW - cocatalyst
KW - electron transfer
KW - mixed anion
KW - photocatalysis
KW - water-splitting
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U2 - 10.1021/acsami.9b14802
DO - 10.1021/acsami.9b14802
M3 - Article
C2 - 31726820
AN - SCOPUS:85076450027
SN - 1944-8244
VL - 11
SP - 45606
EP - 45611
JO - ACS applied materials & interfaces
JF - ACS applied materials & interfaces
IS - 49
ER -
