In the present work we investigate the photocatalytic hydrogen production (water splitting) activity of different Pt loaded TiO2 nanotube layers. Therefore, we fabricate free standing membranes and fix them in four different configurations: top up (with initiation layer "grass" or without) and bottom up (bottom closed or open), then decorate the tubes with various amounts of Pt and measure the open-circuit photocatalytic H-2 production rate. We find a strong influence of the configuration with the open top morphology showing the highest photocatalytic hydrogen production efficiency, these nanotubes yield 3.5 times more H-2 than the least efficient structure (bottom closed). The work therefore provides valuable guidelines for optimizing TiO2 nanotube layers for photocatalytic applications. (C) 2015 Elsevier Ltd. All rights reserved.