Abstract:
Addition of NaBF4 during anodic synthesis of TiO2 nanotube arrays (TNTAs) photocatalyst
and its application for generating hydrogen from glycerolewater solution has been
investigated. The TNTAs were synthesized by anodic oxidation of titanium metal in glycerol electrolyte solution containing NH4F. During the process, the NaBF4 with different
concentrations were added to the solution. Annealing of the formatted TNTAs were performed at 500 C for 3 h under 20% H2 in argon atmosphere, to produce crystalline phase
photocatalyst. FESEM analysis showed that self-organized and well ordered TNTAs have
range of inner diameters, wall thicknesses and lengths approximately 62e130 nm, 27 nm
and 1.53 mm, respectively. FTIR analysis indicated that carbon, nitrogen and boron were
incorporated into the TNTAs lattice. Refer to UVeVis DRS and XRD analysis, the TNTAs
photocatalysts prepared have the band gap range of 2.70e3.10 eV, with mostly have
anatase phase. The NaBF4 addition during synthesis, resulted modified TNTAs that can
reduce the recombination of photo-induced electrons-holes. Photocatalytic hydrogen
production test, from glycerolewater solution, indicated that TNTAs with the addition of
NaBF4 during anodic synthesis process showed higher hydrogen production comparing to
the one without NaBF4 addition. Among them the TNTAs,b (with the addition 5 mM of
NaBF4) showed up to 32% improvement in the hydrogen production and can be considered
as the optimum condition
