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Sensitization of wide band gap photocatalysts to visible light by molten CuCl treatment.

ABSTRACT: Cu(i)-substituted metal oxide photocatalysts were prepared using molten CuCl treatment of wide band gap photocatalysts. The Cu(i)-substituted metal oxide photocatalysts possessed a new absorption band in the visible light region and showed photocatalytic activity for hydrogen evolution from an aqueous solution containing sulfur sacrificial reagents under visible light irradiation. Notably, the Cu(i)-K2La2Ti3O10 and Cu(i)-NaTaO3 photocatalysts showed relatively high activities for hydrogen evolution and gave apparent quantum yields of 0.18% at 420 nm. These photocatalysts responded up to 620 nm. Thus, Cu(i)-substitution using a molten CuCl treatment was an effective strategy for sensitizing a metal oxide photocatalyst with a wide band gap to visible light.

SUBMITTER: Iwashina K

PROVIDER: S-EPMC5590426 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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Sensitization of wide band gap photocatalysts to visible light by molten CuCl treatment.

Iwashina Katsuya K Iwase Akihide A Kudo Akihiko A

Chemical science 20140829 1

Cu(i)-substituted metal oxide photocatalysts were prepared using molten CuCl treatment of wide band gap photocatalysts. The Cu(i)-substituted metal oxide photocatalysts possessed a new absorption band in the visible light region and showed photocatalytic activity for hydrogen evolution from an aqueous solution containing sulfur sacrificial reagents under visible light irradiation. Notably, the Cu(i)-K2La2Ti3O10 and Cu(i)-NaTaO3 photocatalyst ...[more]

PMID: 28936316

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