TY - JOUR
T1 - An effective preparation method of composite photocatalysts for hydrogen evolution using an organic photosensitizer and metal particles assembled on alumina-silica
AU - Yamada, Yusuke
AU - Tadokoro, Hideyuki
AU - Fukuzumi, Shunichi
N1 - Funding Information:
This work was supported by JSPS KAKENHI (Nos. 24350069 and 15K14223 to Y. Yamada) for Scientific Research from Japan Society for the Promotion of Science (JSPS). We sincerely acknowledge the Research Center for Ultra-Precision Science & Technology, Osaka University for TEM measurements.
Publisher Copyright:
© 2016 Elsevier B.V.
PY - 2016/12/1
Y1 - 2016/12/1
N2 - Composite catalysts for photocatalytic hydrogen (H2) evolution were prepared by loading an organic electron donor–acceptor linked dyad [2-phenyl-4-(1-naphthyl)quinolinium ion, QuPh+–NA] as an organic photosensitizer and Pt or Cu particles as H2-evolution catalysts on alumina-silica. The composite catalysts loading Pt particles were prepared by two different methods; first, Pt particles were deposited by reduction of PtCl6 2− owing to photocatalysis of QuPh+–NA supported on alumina-silica (PD method), and second, alumina-silica was impregnated with the PtCl6 2− and calcined, and then QuPh+–NA was loaded on the Pt/alumina-silica by a cation exchange method (IMP method). When a composite catalyst was prepared by the IMP method, a high Pt-loading amount of 4.2 wt% was necessary to achieve the highest H2-evolution rate of 0.27 μmol h−1. On the other hand, a composite catalyst prepared by the PD method exhibited three times faster H2 evolution (0.83 μmol h−1) even though the loading amount of Pt was as low as 0.4 wt%. The activity of composite catalysts prepared by the PD method highly depends on the electric charges of precursors for Pt particles. A composite catalyst prepared with positively charged Pt(NH3)4 2+ as a precursor of Pt particles exhibited low catalytic activity with the H2-evolution rate of 0.10 μmol h−1, which is significantly lower than the rate (0.27 μmol h−1) for the composite catalyst prepared with PtCl6 2−. However, such precursor-dependence was not observed for composite catalysts employing Cu particles as an H2-evolution catalyst, because the Cu precursors are more labile than the Pt precursors in a reaction solution. The electrostatic interaction between the precursors of metal particles and negatively charged surfaces of alumina-silica should be taken into account to construct efficient H2-evolution catalysts.
AB - Composite catalysts for photocatalytic hydrogen (H2) evolution were prepared by loading an organic electron donor–acceptor linked dyad [2-phenyl-4-(1-naphthyl)quinolinium ion, QuPh+–NA] as an organic photosensitizer and Pt or Cu particles as H2-evolution catalysts on alumina-silica. The composite catalysts loading Pt particles were prepared by two different methods; first, Pt particles were deposited by reduction of PtCl6 2− owing to photocatalysis of QuPh+–NA supported on alumina-silica (PD method), and second, alumina-silica was impregnated with the PtCl6 2− and calcined, and then QuPh+–NA was loaded on the Pt/alumina-silica by a cation exchange method (IMP method). When a composite catalyst was prepared by the IMP method, a high Pt-loading amount of 4.2 wt% was necessary to achieve the highest H2-evolution rate of 0.27 μmol h−1. On the other hand, a composite catalyst prepared by the PD method exhibited three times faster H2 evolution (0.83 μmol h−1) even though the loading amount of Pt was as low as 0.4 wt%. The activity of composite catalysts prepared by the PD method highly depends on the electric charges of precursors for Pt particles. A composite catalyst prepared with positively charged Pt(NH3)4 2+ as a precursor of Pt particles exhibited low catalytic activity with the H2-evolution rate of 0.10 μmol h−1, which is significantly lower than the rate (0.27 μmol h−1) for the composite catalyst prepared with PtCl6 2−. However, such precursor-dependence was not observed for composite catalysts employing Cu particles as an H2-evolution catalyst, because the Cu precursors are more labile than the Pt precursors in a reaction solution. The electrostatic interaction between the precursors of metal particles and negatively charged surfaces of alumina-silica should be taken into account to construct efficient H2-evolution catalysts.
KW - Hydrogen production
KW - Organic photosensitizer
KW - Photocatalyst
KW - Preparation method
UR - http://www.scopus.com/inward/record.url?scp=84957403447&partnerID=8YFLogxK
U2 - 10.1016/j.cattod.2016.01.018
DO - 10.1016/j.cattod.2016.01.018
M3 - Article
AN - SCOPUS:84957403447
SN - 0920-5861
VL - 278
SP - 303
EP - 311
JO - Catalysis Today
JF - Catalysis Today
ER -