One-dimensional (1D) ordered TiO
2
nanotubes
exhibit
exceptional charge transfer capabilities, making them suitable candidates
for constructing visible-light-active photoanodes in selective PEC
oxidation reactions. Herein, we employed a facile and easily scalable
electrochemical method to fabricate Au-CoO
x
-deposited ordered TiO
2
nanotubular array photoanodes.
The improved visible light absorption capacity of TiO
2
-Au-CoO
x
, with unhampered 1D channels and the controlled
integration of Au between TiO
2
and CoO
x
, along with their synergistic interaction, have been identified
as the most promising strategy for enhanced PEC performance, as evidenced
by an IPCE of 3.7% at 450 nm. Furthermore, the robust interfacial
charge transfer pathway from CoO
x
to the
TiO
2
surface via the Au mediator promotes the migration
of photogenerated electrons and enables the accumulation of holes
on the surface of CoO
x
. These holes are
then efficiently utilized by oxidants such as methanol or lignin to
generate value-added products, highlighting the potential of this
system for advanced PEC applications.