Ti–Ta mixed oxide freestanding nanotubes obtained by means of anodic oxidation of a homemade Ti–Ta (50–50 at%) alloy.

Abstract

The present work evaluated the effect on charge transfer in functionalized TiO 2 nanostructured systems using different binders. We highlight the conditions required to form self-assembled systems by varying the number of layers, as well as by substituting them for an organic binder, cysteine. Additionally, we study the pH effect of the precursor solution (HAuCl 4 ) on gold nanoparticles (AuNPs) formation. The morphological characterization allowed us to determine the percentage of Au atoms on the surface of the synthesized nanoparticles. Inductively coupled plasma mass spectrometry (ICP-MS) analysis determined the amount of gold deposited on the TiO 2 surface, which ranged from 4.56 to 253.00 ng mm -2 depending on the system used. Based on Fourier-transform infrared spectroscopy (FTIR) and Raman analysis, it was possible to propose a photolysis mechanism for AuNP formation in accordance with the change in the binders. The different systems were subjected to hydrogen photogeneration by a water splitting process, resulting in 2.02 μmol cm -2 of hydrogen production for cysteine binder [Cys+HAuCl 4 -2.7]. There proved to be an excellent synergy between the morphological aspects, crystallinity, and stability of this arrangement.