TY  - JOUR
A1  - Öner, Ibrahim Halil
A1  - Querebillo, Christine Joy
A1  - David, Christin
A1  - Gernert, Ulrich
A1  - Walter, Carsten
A1  - Driess, Matthias
A1  - Leimkühler, Silke
A1  - Ly, Khoa Hoang
A1  - Weidinger, Inez M.
T1  - High electromagnetic field enhancement of TiO2 nanotube electrodes
JF  - Angewandte Chemie : a journal of the Gesellschaft Deutscher Chemiker ; International edition
N2  - We present the fabrication of TiO2 nanotube electrodes with high biocompatibility and extraordinary spectroscopic properties. Intense surface-enhanced resonance Raman signals of the heme unit of the redox enzyme Cytochromeb(5) were observed upon covalent immobilization of the protein matrix on the TiO2 surface, revealing overall preserved structural integrity and redox behavior. The enhancement factor could be rationally controlled by varying the electrode annealing temperature, reaching a record maximum value of over 70 at 475 degrees C. For the first time, such high values are reported for non-directly surface-interacting probes, for which the involvement of charge-transfer processes in signal amplification can be excluded. The origin of the surface enhancement is exclusively attributed to enhanced localized electric fields resulting from the specific optical properties of the nanotubular geometry of the electrode.
KW  - electromagnetic field enhancement
KW  - photonic crystals
KW  - spectro-electrochemistry
KW  - surface-enhanced Raman spectroscopy
KW  - TiO2 nanotubes
Y1  - 2018
U6  - https://doi.org/10.1002/anie.201802597
SN  - 1433-7851
SN  - 1521-3773
VL  - 57
IS  - 24
SP  - 7225
EP  - 7229
PB  - Wiley-VCH
CY  - Weinheim
ER  -