(Gold core)/(titania shell) nanostructures for plasmon-enhanced photon harvesting and generation of reactive oxygen species

Abstract
Integration of gold and titania in a nanoscale core/shell architecture can offer large active metal/semiconductor interfacial areas and avoid aggregation and reshaping of the metal nanocrystal core. Such hybrid nanostructures are very useful for studying plasmon-enhanced/enabled processes and have great potential in light-harvesting applications. Herein we report on a facile route to (gold nanocrystal core)/(titania shell) nanostructures with their plasmon band synthetically variable from ∼700 nm to over 1000 nm. The coating method has also been applied to other mono- and bi-metallic Pd, Pt, Au nanocrystals. The gold/titania nanostructures have been employed as the scattering layer in dye-sensitized solar cells, with the resultant cells exhibiting a 13.3% increase in the power conversion efficiency and a 75% decrease in the scattering-layer thickness. Moreover, under resonant excitation, the gold/titania nanostructures can efficiently utilize low-energy photons to generate reactive oxygen species, including singlet oxygen and hydroxyl radicals.

Citation
Fang, C., Jia, H., Chang, S., Ruan, Q., Wang, P., Chen, T., & Wang, J. (2014). (Gold core)/(titania shell) nanostructures for plasmon-enhanced photon harvesting and generation of reactive oxygen species. Energy Environ. Sci., 7(10), 3431–3438. doi:10.1039/c4ee01787k

Acknowledgements
This work was supported by Hong Kong RGC GRF (Ref. no.: CUHK403312, Project Code: 2130320) and NNSFC (Ref. no.: 21229101).

Publisher
Royal Society of Chemistry (RSC)

Journal
Energy Environ. Sci.

DOI
10.1039/c4ee01787k

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