6533b838fe1ef96bd12a4e5f

RESEARCH PRODUCT

Ag sensitized TiO2 and NiFe2O4 three-component nanoheterostructures: synthesis, electronic structure and strongly enhanced visible light photocatalytic activity

Tanel KäämbreMārtiņš VanagsVambola KisandNicola DöbelinAndris ŠUtkaAndris ŠUtkaKrisjanis SmitsRainer Pärna

subject

Materials sciencebusiness.industryGeneral Chemical EngineeringNanoparticleHeterojunction02 engineering and technologyGeneral ChemistryElectronic structure010402 general chemistry021001 nanoscience & nanotechnology01 natural sciences0104 chemical sciencesElectron transferPhotocatalysisOptoelectronicsCharge carrier0210 nano-technologybusinessTernary operationVisible spectrum

description

This study reports on the synthesis and characterisation of two- and three-component visible light active photocatalytic nanoparticle heterostructures, based on TiO2 and NiFe2O4 and sensitized with Ag. We observe that a Ag content as small as 1 at% in the TiO2/NiFe2O4 heterostructure increases by more than an order of magnitude the rate constant for the visible light photocatalytic process. We rationalise this in terms of the measured structure and electronic structure data of the binary and ternary combinations of the component materials and focus on details, which show that an optimised deposition sequence is vital for attaining high values of photocatalytic efficiency, because the charge transfer across the interfaces appears to be sensitive to where the Ag is loaded in the heterostructure. The overall higher visible light photocatalytic activity of the TiO2/Ag/NiFe2O4 heterostructure was observed and is attributed to enhanced charge carrier separation efficiency and migration via vectorial electron transfer.

https://doi.org/10.1039/c6ra00728g