Influence of the Dopant Concentration on the Photoelectrochemical Behavior of Al-Doped TiO₂

Abstract

In the present study, we explored the effect of Al-dopant concentration within the range of <1.1 wt % on the photoelectrochemical (PEC) activity of an Aldoped TiO 2 photoanode. The experimental dependencies of PEC efficiency on Aldopant concentration indicate that there is an optimal Al concentration of 0.5 wt % corresponding to the highest photoactivity. The analysis of the spectral dependencies

Degradation of Fluoroquinolone-Based Pollutants and Bacterial Inactivation by Visible-Light-Active Aluminum-Doped TiO2 Nanoflakes

“…Multipoint BET indicates that the lowest surface area corresponds to undoped TiO 2 (202 m 2 /g), which exhibits a type II adsorption−desorption isotherm presenting a nonporous nature of the 0% AT photocatalyst. 26 However, the surface area value was found to increase initially with the added dopant, i.e., 0% AT (202 m 2 /g) < 0.5% AT (231 m 2 /g) < 1% AT (355 m 2 /g), as presented in Table S2, in accordance with the results reported by Murashkina et al 25 Subsequently, a further increase in the Al concentration did not show any positive role in increasing the surface area. This might be due to the possible segregation of Al in the TiO 2 matrix beyond a critical concentration of 1%.…”

“…As reported previously, a dopant could significantly tune the porosity of TiO 2 and, hence, can affect the catalytic ability of a catalyst . A nitrogen adsorption–desorption study was performed (Figure S4) in order to observe any changes in the porosity of TiO 2 nanoflakes with Al doping.…”

“…24 As reported previously, a dopant could significantly tune the porosity of TiO 2 and, hence, can affect the catalytic ability of a catalyst. 25 A nitrogen adsorption−desorption study was performed (Figure S4) in order to observe any changes in the porosity of TiO 2 nanoflakes with Al doping. The surface area variation with increasing Al doping is plotted in Figure 3b, and the total pore volume and surface area of various catalysts are compiled in Table S2.…”

“…30 The incorporation of Al beyond 1% does not lead to a variation in the density of states compared with TiO 2 . As an effect of Al doping, reduction of the band gap of semiconductors like TiO 2 25 and ZnO 31 is reported in the literature. In this work, even 0.5% doping of an Al precursor affects the band gap and favors a red shift in the band-gap value in comparison to undoped TiO 2 (3.27 eV for 0% AT to 2.92 eV for 0.5% AT).…”

Different Enhancement Mechanisms of the Anodizing Al‐Doped or Sn‐Coupled Ti3SiC2 for the Photoelectrochemical Performance

“…Secondly, the strategy feasibility of metal doping into Ti 3 SiC 2 and TiO 2 successively is confirmed by the main phase of Al‐TiO 2 in Al‐ATSC. The Al‐dopant affects both the number and type of compensating defects . The photo‐generated electrons can easily be trapped and move to the conduction band of Al‐TiO 2 which results in the optimal dopant concentration of Al0.5‐ATSC for the higher PEC activity.…”