Sub-10-nm Mixed Titanium/Tantalum Oxide Nanoporous Films with Visible-Light Photocatalytic Activity for Water Treatment

Abstract

In the present work, anodic mixed titanium/tantalum oxide nanotubes are prepared for the first time with sub-10-nm surface pore size and tube inner diameter. The morphological changes induced by the introduction of Ta into the Ti metal matrix are investigated, leading to remarkable geometrical variations dependent on the Ta loading. The UVlight activation necessary to trigger electron transfer in TiO 2 limits the range of applications, and the shift in light absorption toward the visible range represents a significant challenge. Here, the band gaps of the as-created nanotube thin-film arrays are calculated, and the results, showing the presence of a minimum in the band gap, correlated to the presence of titanium and tantalum suboxides and Ta loading. The potential of the thin films as advanced materials for photocatalytic water treatment is tested against that of pure TiO 2 , and an enhancement in the visible-light absorption and an almost 3-fold increase in the degradation kinetics under pure visiblelight irradiation are demonstrated.

Niobium–Zirconium Oxynitride Nanotube Arrays for Photoelectrochemical Water Splitting

“…Yang et al 19 investigated the effect of adding Nb to TiO 2 NTs and concluded that Nb increased the electron mobility in the mixed Ti−Nb oxide. Merenda et al 20 studied the effect of incorporating tantalum (Ta), as a transition metal, on the stability and catalytic performance of titanium dioxide. They concluded that Ta content has a valuable role in overcoming the titanium dioxide corrosion problems and largely contributed in narrowing its bandgap energy.…”

Engineering high-defect densities across vertically-aligned graphene nanosheets to induce photocatalytic reactivity

“…The asymmetry in the C1s sp 2 and sp 3 peaks were fitted by Gaussian/Lorentzian product modified by an asymmetric form A(a,b,n)GL(p) after Shirley background subtraction. The a and b fitting parameters were fixed at 0.1 to determine the shape 10 of the asymmetric portion of the curve and n was kept at 80 for defining the optimal convolution width of the modelled line-shapes [49]. 11…”

Bi–Sn Catalytic Foam Governed by Nanometallurgy of Liquid Metals

“…This phenomenon, resulting in a shift from 532.7 to 532.2 eV, was related to the appearance of Metal−OH bonds typically located between 531.5 and 532 eV, that can be attributed to In (III) species. 30,35 No significant variation in the Sn 2p spectra compared to the Bi 53 Sn 47 particles could be observed, meaning that there is no evidence of reduction of Sn oxides to Sn(0). The raw HR XPS spectra of the EBi 53 Sn 47 and Bi 52 Sn 46 In 2 foams are reported in the Figure S3.…”