Photoelectrochemical characterisation and photocatalytic activity of composite La2O3–TiO2 coatings on stainless steel

Enhanced Photoelectrocatalytic Degradation of Methylene Blue on Smooth TiO[sub 2] Nanotube Array and Its Impedance Analysis

“…+0.3 V. In the base solution, only H 2 O was oxidized at TiO 2 electrode surface by the photogenerated holes, while both H 2 O and organic species were oxidized in organic solutions. The lack of direct relationship between the photocurrent and the actual PEC degradation rate, especially at relatively high potentials, may be explained in the following aspects: ͑i͒ it may be associated with the faster charge transfer rate by field-driven migration, which is dependent on applied potential; ͑ii͒ the ohmic losses decrease the effective potential from the value applied between the reference electrode tip and the current collector at locations around the tip to some extent should also be taken into account; 40 ͑iii͒ most importantly, it should be emphasized that more positive applied potential favors the specific adsorption of Cl − on the surface of TiO 2 nanotube array electrode, and therefore, in situ photoelectrochemical generated active chlorine ͑Cl 2 , HClO, ClO − ͒ as powerful oxidizing species that can diffuse into bulk solution is responsible for the further enhancement of degradation rate of MB with increasing positive applied potential. 39 Because the rate of a heterogeneous photoelectrochemical reaction is proportional to the surface concentration of photogenerated holes and electrons and, in the case of a positively biased TiO 2 catalyst, the electrons flow through the external circuit and the resulting photocurrent density should be analogous to the reaction rate.…”

Correlation between photoelectrochemical behaviour and photoelectrocatalytic activity and scaling-up of P25-TiO2 electrodes

“…Finally, possible commercial applications requires carrying out the scaling-up of photoelectrodes to be used in a photoelectrocatalytic reactor instead of in a small electrochemical cell, where the photoelectrochemical behaviour of the photoelectrodes is usually studied. Some authors have pointed out the differences observed in efficiency or parameters such as potential bias that should be modified when photoelectrodes are scaled up [7,9]. Therefore, the aim of this work is to investigate the correlation between the electrochemical characterization of different TiO 2 electrodes and their photoelectrocatalytic activity, evaluating if the ratio between the photocurrent and photoelectrocatalytic activity of photoelectrodes is kept constant after being scaled up.…”

Photocatalytic degradation on Disperse Blue with modified nano-TiO2 film electrode

“…Modification can not only improve the photocatalytic activity of TiO 2 towards the degradation on organic pollutants but also result in the expansion of photosensitivity to the visible light region [6]. Marta Mrowetz et al [7] found that nitrogen doping could extend the absorption of TiO 2 into the visible light region.…”