Effect of anodization voltage on performance of TiO_2 nanotube arrays for hydrogen generation in a two-compartment photoelectrochemical cell

摘要

Highly ordered TiO_2 nanotube arrays were prepared by anodic oxidation of Ti foil under different anodization voltages in ethylene glycol electrolyte. The morphology and photo-electrochemical performance of the TiO_2 nanotubes (NTs) samples were characterized by FESEM and electrochemical working station. Hydrogen production was measured by splitting water in the two-compartment photoelectrochemical (PEC) cell without any external applied voltage or sacrificial agent. The results indicated that anodization voltage significantly affects morphology structures, photoelectrochemical properties and hydrogen production of TiO_2 NTs. The pore diameter and layer thickness of TiO_2 samples increased linearly with the anodization voltage, which led to the enhancement of active surface area. Accordingly, the photocurrent response, photoconversion efficiency and hydrogen production of TiO_2 nanotubes were also linearly correlated with the anodization voltage.