Intrinsic Au decoration of growing TiO₂ nanotubes and formation of a high-efficiency photocatalyst for H₂ production

Electrochemical anodization of low-concentration (0.02-0.2 at% Au) TiAu alloys in a fluoride electrolyte leads to self-organized TiO₂ nanotubes that show a controllable, regular in situ decoration with elemental Au nanoclusters of ≈5 nm in diameter. The degree of self-decoration can be adjusted by the Au concentration in the alloy and the anodization time. Such Au particle decorated tubes show a high activity for photocatalytic H₂ production from ethanol solutions.