  In the present work we use TiO2 nanotube arrays, carrying a Pt coating that
is optimally dewetted, as a photocatalyst to generate H2. In order to achieve a
maximum H2-generation efficiency, on the one hand an ideal thermal dewetting of
the Pt layer into nanoparticles is needed that requires an oxygen free heat
treatment, and on the other hand an optimal crystallization of the TiO2
nanotubes into anatase with reduced defect density is achieved only by
annealing in O2 containing environment. To overcome this issue, we combine
adequate reducing and oxidizing conditions in a multiple annealing treatment,
and obtain Pt-decorated anatase TiO2 nanotubes showing significantly enhanced
photocatalytic H2 generation ability.

Materials Science