Uniform ALD deposition of Pt nanoparticles within 1D anodic TiO2 nanotubes for photocatalytic H-2 generation

Abstract

In the present work we investigate the utilization of Pt nanoparticles produced by atomic layer deposition (ALD) within anodic TiO2 nanotube (NT) layers for photocatalytic H-2 production. By varying the number of ALD cycles, Pt nanoparticles with different diameters were produced, uniformly decorating the tube walls. The Pt nano-particle size (2-15 nm), the Pt mass loading and areal density were strongly dependent on the number of Pt ALD cycles. The deposited Pt nanoparticles turned out to be highly effective as a co-catalyst for photocatalytic H-2 generation. The most effective performance for solar light photocatalysis was reached after 26 ALD cycles (yielding an optimal area coverage with particles of diameter approximate to 7 nm). For UV light, the optimum photocatalytic efficiency was reached after 40 ALD cycles.