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Hydrogen production by tuning the photonic band gap with the electronic band gap of TiO?.

ABSTRACT: Tuning the photonic band gap (PBG) to the electronic band gap (EBG) of Au/TiO2 catalysts resulted in considerable enhancement of the photocatalytic water splitting to hydrogen under direct sunlight. Au/TiO2 (PBG-357 nm) photocatalyst exhibited superior photocatalytic performance under both UV and sunlight compared to the Au/TiO2 (PBG-585 nm) photocatalyst and both are higher than Au/TiO2 without the 3 dimensionally ordered macro-porous structure materials. The very high photocatalytic activity is attributed to suppression of a fraction of electron-hole recombination route due to the co-incidence of the PBG with the EBG of TiO2 These materials that maintain their activity with very small amount of sacrificial agents (down to 0.5 vol.% of ethanol) are poised to find direct applications because of their high activity, low cost of the process, simplicity and stability.

SUBMITTER: Waterhouse GI

PROVIDER: S-EPMC3794377 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

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Hydrogen production by tuning the photonic band gap with the electronic band gap of TiO₂.

Waterhouse G I N GI Wahab A K AK Al-Oufi M M Jovic V V Anjum D H DH Sun-Waterhouse D D Llorca J J Idriss H H

Scientific reports 20131010

Tuning the photonic band gap (PBG) to the electronic band gap (EBG) of Au/TiO2 catalysts resulted in considerable enhancement of the photocatalytic water splitting to hydrogen under direct sunlight. Au/TiO2 (PBG-357 nm) photocatalyst exhibited superior photocatalytic performance under both UV and sunlight compared to the Au/TiO2 (PBG-585 nm) photocatalyst and both are higher than Au/TiO2 without the 3 dimensionally ordered macro-porous structure materials. The very high photocatalytic activity i ...[more]

PMID: 24108361

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