TY  - JOUR
A1  - Sivanesan, Arumugam
A1  - Ly, Khoa H.
A1  - Adamkiewicz, Witold
A1  - Stiba, Konstanze
A1  - Leimkühler, Silke
A1  - Weidinger, Inez M.
T1  - Tunable electric field enhancement and redox chemistry on TiO2 Island films via covalent attachment to Ag or Au nanostructures
JF  - The journal of physical chemistry : C, Nanomaterials and interfaces
N2  - Ag-TiO2 and Au-TiO2 hybrid electrodes were designed by covalent attachment of TiO2 nanoparticles to Ag or Au electrodes via an organic linker. The optical and electronic properties of these systems were investigated using the cytochrome b(5) (Cyt b(5)) domain of sulfite oxidase, exclusively attached to the TiO2 surface, as a Raman marker and model redox enzyme. Very strong SERR signals of Cyt b(5) were obtained for Ag-supported systems due to plasmonic field enhancement of Ag. Time-resolved surface-enhanced resonance Raman spectroscopic measurements yielded a remarkably fast electron transfer kinetic (k = 60 s(-1)) of Cyt b(5) to Ag. A much lower Raman intensity was observed for Au-supported systems with undefined and slow redox behavior. We explain this phenomenon on the basis of the different potential of zero charge of the two metals that largely influence the electronic properties of the TiO2 island film.
Y1  - 2013
U6  - https://doi.org/10.1021/jp4032578
SN  - 1932-7447
VL  - 117
IS  - 22
SP  - 11866
EP  - 11872
PB  - American Chemical Society
CY  - Washington
ER  -