Applied Surface Science, Vol.357, 214-220, 2015
All electrochemical fabrication of a bilayer membrane composed of nanotubular photocatalyst and palladium toward high-purity hydrogen production
We developed an all-electrochemical technique for fabricating a bilayer structure of a titanium dioxide (TiO2) nanotube array (TNA) and a palladium film (TNA/Pd membrane), which works for photocatalytic high-purity hydrogen production. Electroless plating was used for depositing the Pd film on the TNA surface prepared by anodizing a titanium foil. A 3-mu m-thick TNA/Pd membrane without any pinholes in a 1.5-cm-diameter area was fabricated by transferring a 1- mu m-thick TNA onto an electroless-plated 2-mu m-thick Pd Pd film with a mechanical peel-off process. This ultrathin membrane with sufficient mechanical robustness showed photocatalytic H-2 production via methanol reforming under ultraviolet illumination on the TNA side, immediately followed by the purification of the generated H2 gas through the Pd layer. The hydrogen production rate and the apparent quantum yield for high-purity H2 production from methanol/water mixture with the TNA/Pd membrane were also examined. This work suggests that palladium electroless plating is more suitable and practical for preparing a well-organized TNA/Pd heterointerface than palladium sputter deposition. (C) 2015 Elsevier B.V. All rights reserved.
Keywords:Photocatalysis;High purity hydrogen production;Anodized TiO2 nanotube array;Hydrogen permeable metal;Electroless plating