Assembly and Photocarrier Dynamics of Heterostructured Nanocomposite Photoanodes from Multicomponent Colloidal Nanocrystals

Nano Lett. 2015 Nov 11;15(11):7347-54. doi: 10.1021/acs.nanolett.5b03871. Epub 2015 Oct 14.

Abstract

Multicomponent oxides and their heterostructures are rapidly emerging as promising light absorbers to drive oxidative chemistry. To fully exploit their functionality, precise tuning of their composition and structure is crucial. Here, we report a novel solution-based route to nanostructured bismuth vanadate (BiVO4) that facilitates the assembly of BiVO4/metal oxide (TiO2, WO3, and Al2O3) nanocomposites in which the morphology of the metal oxide building blocks is finely tailored. The combination of transient absorption spectroscopy-spanning from picoseconds to second time scales-and photoelectrochemical measurements reveals that the achieved structural tunability is key to understanding and directing charge separation, transport, and efficiency in these complex oxide heterostructured films.

Keywords: Colloidal synthesis; assembly; charge dynamics; photoelectrochemistry; ternary oxides.