Nitrogen-Doped TiO₂Nanotube Arrays with Enhanced Photoelectrochemical Property

Abstract

N-doped TiO2nanotube arrays were prepared by electrochemical anodization in glycerol electrolyte, followed by electrochemical deposition in NH4Cl solution. An orthogonal experiment was used to optimize the doping conditions. Electrolyte concentration, reaction voltage, and reaction time were the main factors to influence the N-doping effect which was the determinant of the visible range photoresponse. The optimal N-doping conditions were determined as follows: reaction voltage is 3 V, reaction time is 2 h, and electrolyte concentration is 0.5 M. The maximal photocurrent enhanced ratio was 30% under white-light irradiation. About 58% improvement of photocatalytic efficiency was achieved in the Rhodamine B degradation experiment by N doping. The kinetic constant of the N-doped TNT arrays sample was almost twice higher than that of the undoped sample. Further analysis by X-ray photoelectron spectroscopy supported that electrochemical deposition is a simple and efficient method for N doping into TiO2nanotube arrays.

Fabrication, Modification, and Emerging Applications of TiO2Nanotube Arrays by Electrochemical Synthesis: A Review

“…The results indicated that the visible light absorption and photoelectrochemical activities of these doped crystallized TNAs were not only influenced by the energy gaps and the distributions of impurity states but were also affected by the locations of Femi levels and the energies of band gap edges [50,51]. Among all these anions, the doping of TNAs with nitrogen or carbon has been found to receive significant attention [52][53][54][55][56][57][58][59]. Highly promising N-doping approach for TNAs includes one-step direct electrochemical anodization of a TiN alloy or growing TNAs in a solution containing doping species [59].…”

Novel nitrogen precursors for electrochemically driven doping of titania nanotubes exhibiting enhanced photoactivity

“…Another way to incorporate nitrogen atoms is realized by N-ion bombardment at variable angles. 32 However, despite using KOH solution as a hole scavenger medium during the photocurrent measurements, the highest current enhancement ratio reported for N-doped titania nanotube arrays was only 30% higher compared to pure TiO 2 . As an alternative option, the immersion of as-prepared titania nanotubes in the solution of ammonia 24,25 or hydrazine hydrate 26 for a long time (6-10 hours) followed by thermal annealing in an ambient atmosphere was proposed.…”

Computational study of TiO2 Brookite (100), (010) and (210) surface doped with Ruthenium for application in Dye Sensitised Solar Cells

“…Consistent analysis of the changes induced by impurities implies a detailed comparison of the calculated properties of the undoped and doped materials [8,10,11]. Such an approach is used in the present work, whereby first principle method is employed to calculate structural and electronic properties of brookite TiO 2 surfaces for both pure and Ru-doped systems.…”

“…As a result, the properties of pure brookite are poorly known. TiO 2 can only show photocatalytic activity under ultraviolet (UV) light irradiation (λ < 387.5 nm) that accounts for only a small portion of solar energy (approximately 5%), in contrast to visible light for a major part of solar energy (approximately 45%), but can be photosensitized by the adsorption of chromophores that, when excited, inject electrons into the TiO 2 conduction band [8]. In spite of a large number of publications on pure and doped TiO 2 many aspects of…”