Pure TiO2 Nanotube Arrays Research Articles

A highly efficient In2S3/Ag2S/TiO2 NTAs photoelectrodes for photocathodic protection of Q235 carbon steel under visible light

A novel In2S3/Ag2S/TiO2 nanotube arrays (NTAs) was successfully fabricated by successive ionic layer adsorption and reaction method and electrochemical anodic oxidation method, and served as photoanode for photocathodic protection application. The micromorphologies, optical absorption properties, crystalline structure and elemental valence states of the composites were performed by field emission scanning electron microscopy, high resolution transmission electron microscope, UV–vis diffuse reflectance absorption spectra, x-ray diffractometer and x-ray photoelectron spectroscopy, respectively. The photocathodic protection performances of In2S3/Ag2S/TiO2 NTAs on the Q235 carbon steel (CS) were also studied. The In2S3/Ag2S/TiO2 nanocomposites show better photoelectrocatalytic and photocathodic protection performance than pure TiO2 NTAs. The photocurrent density of In2S3(9)/Ag2S(8)/TiO2 photoelectrode coupled with Q235 CS reach 211 μA cm−2, which is about 4.5 times higher than that of TiO2 NTAs. The photogenerated potential of Q235 CS coupled to In2S3(9)/Ag2S(8)/TiO2 under illumination shows a negative shift to −0.92 V versus SCE. Results indicate that the co-sensitization of In2S3 and Ag2S could extend the light absorption of TiO2 to the visible light range and enhance its photoelectric conversion efficiency.

N-doped TiO2 nanotube arrays with mixed phase for enhanced photocathodic protection of 304 stainless steel under visible light

Effective N-doped TiO2 nanotube arrays with rutile–anatase mixed phase were fabricated by two-step anodization method and annealing in a NH3 atmosphere. Compared with pure anatase TiO2 nanotube arrays, the photocurrent density of N-doped TiO2 nanotube arrays with mixed phase increased by about three times under visible light. Moreover, the open circuit potential of 304 stainless steel obviously negatively shifted when coupled with N-doped TiO2 nanotube arrays with mixed phase under visible light. The enhancement was mainly because N-doping extends light absorbance and the mixed phase is beneficial for the separation of photoexcited electrons–holes. Therefore, N-doped TiO2 nanotube arrays with mixed phase showed highly effective photogenerated cathodic protection of 304 stainless steel under visible light. Interestingly, the photoelectrode also displayed a cathodic protection effect after removing irradiation, which is meaningful for practical applications.

Atom substitution method to construct full-solar-spectrum absorption MoSeS/TiO2 nanotube arrays for highly efficient hydrogen evolution

Two-dimensional semiconductor shows highly efficient photocatalytic H2 generation due to plasma enhancement effect. Herein, a large area layered MoSeS in conjunction with TiO2 nanotube arrays is achieved by Ti foil anodization and chemical vapor deposition processes. MoSeS/TiO2 heterojunction has been prepared by one-step and two-step atom substitution methods, we found that the one-step atomic substitution method had higher photocatalytic performance than that. The composites can greatly reduce the charge transfer resistance and accelerate the carrier transport, leading to a high photocurrent response. UV–vis absorption spectra indicated an obvious redshift, which greatly improved the utilization efficiency of visible light. Photoelectrochemical properties of the composites showed that one-step atom substituted MoSeS has the highest performance. For the MoSeS/TiO2 by one-step (ES-TNTs), the hydrogen production efficiency reaches 92.74μmolh−1cm−2, which is 11 times higher than that of pure TiO2 nanotube arrays (TNTs). Also, the photocurrent density is 1.2 mAcm−2 at a bias of 0V, which is about 6 times higher than that of pure TNTs. In comparison to the two-step atom substitution method (S-E-TNTs, E-S-TNTs), the result is that MoSeS is easy to agglomerate on the surface of TNTs, which greatly reduces the contacted area and photocurrent density.

A novel CaIn2S4/TiO2 NTAs heterojunction photoanode for highly efficient photocathodic protection performance of 316 SS under visible light

Designing heterojunction photocatalysts with matched band structure and good interface contact is an effective method to improve the photoelectrochemical activity. Herein, novel CaIn2S4/TiO2 nanotube arrays (NTAs) heterojunction photoanodes were successfully prepared by electrochemical anodization and hydrothermal method. The microstructures, compositions, crystal structures, chemical valence states and light absorption performances of the composites were evaluated by field emission scanning electron microscopy, energy dispersive x-ray spectroscopy transmission electron microscope, high-resolution transmission electron microscope, x-ray diffractometer, x-ray photoelectron spectroscopy and ultraviolet–visible diffuse reflectance spectroscopy (UV–vis DRS), respectively. The photocathodic protection performances of CaIn2S4/TiO2 composites for 316 stainless steel (SS) and the influences of the CaIn2S4 content on the performances were studied. The microstructural examination revealed the uniform doping of CaIn2S4 nanofragments on the TiO2 NTAs, and the composite was made up cubic CaIn2S4 and anatase TiO2. The photogenerated electrons were transferred from the TiO2 to CaIn2S4 at the interface of the composite. Compared with pure TiO2 NTAs, CaIn2S4/TiO2 NTAs exhibited better photocathodic protection performance for 316 SS under visible light. Potential drop reached 0.78 V versus saturated calomel electrode for the 316 SS coupled with CaIn2S4/TiO2 NTAs. The photocurrent density of the 316 SS coupled with the composite photoanode (235.4 μA cm–2) was 17.4 times that of TiO2. The improved photocathodic protection property of CaIn2S4/TiO2 NTAs was ascribed to the enhanced separation efficiency of the photogenerated carriers and the strong visible light absorption of the material. The CaIn2S4/TiO2 NTAs exhibited continuous protection of the 316 SS for more than 12 h even in the dark. Therefore, the CaIn2S4/TiO2 NTAs heterojunction composite is an outstanding and efficient photoanode for the photocathodic protection of metals.

Co3O4 Decorated Ti/TiO2 Nanotubes for Photogenerated Cathodic Protection of 304 Stainless Steel

The Co3O4 decorated TiO2 nanotube arrays(NTAs) coatings are fabricated by the combination of anodization and impregnating methods. It is found that the introduction of Co3O4 can reduce the diffraction intensity of (101) plane of the TiO2 and accelerate the separation of photogenerated electron/hole pairs. In addition, the open circuit potential(OCP) and the corrosion potential of 304 stainless steel(304SS) with or without Co3O4 decorated TiO2 NTAs were measured under visible light, which indicated the 304SS coupled with Co3O4 decorated TiO2 NTAs had better anticorrosion performance than that of the 304SS or the 304SS coupled with pure TiO2 NTAs. The enhancement of the cathodic protection performance of the Co3O4 decorated TiO2 NTAs can be ascribed to the matched energy levels and strong interaction between Co3O4 and TiO2 NTAs, and the improvement of light absorption.

Cu2O on anodised TiO2 nanotube arrays: A heterojunction photoanode for visible light assisted electrochemical degradation of pharmaceuticals in water

A visible-light active p-n heterojunction photoanode was synthesised via electrodeposition of Cu2O on anodised TiO2 nanotube arrays (NTAs). The photoanode was characterised with XRD, FESEM, EDX and diffusive reflectance UV–Vis, and evaluated by the degradation of ciprofloxacin in water. Mott-Shottky plots were carried out to confirm the formation of the p-n heterojunctions between the two electrodes. Photoelectrochemical properties of the synthesised photoanode were also examined with linear sweep voltammetry, photocurrent response and electrochemical impedance spectroscopy. The linear sweep voltammetry showed that the TiO2 NTA/Cu2O photoanode gave the highest current as compared to the pristine TiO2 NTA. In addition, photocurrent response study showed that the TiO2 NTA/Cu2O gave an improved response three times (0.169 mA cm−2) larger than the pure TiO2 NTA (0.05 mA cm−2). The as-prepared photoanodes were applied in the photoelectrocatalytic degradation of ciprofloxacin an antibiotic. An overall percentage degradation of 73% over a period of 4 h. Trapping experiment revealed that the degradation occurred majorly through the holes on the semiconductor. The photoanodes displayed high stability and reusability and therefore suggests the electrodeposited Cu2O anodised TiO2 NTA electrode as an efficient photoanode for degrading other emerging pharmaceutical pollutants from wastewater.

Optimal engineering of CdS/PbS co-sensitized TiO2 nanotube arrays for enhanced photoelectrochemical performance

TiO2 nanotube arrays (NTAs) are decorated with CdS/PbS nano-sensitizers by successive ionic layer adsorption and reaction (SILAR) method. The uniform growth of the CdS and PbS nanoparticles on the surface and inner side of TiO2 Nanotube Arrays (NTAs) has been confirmed by Transmission Electron microscopy measurements. The impact of the CdS and PbS semiconductor quantum dots (SQDs) on the photoelectrochemical performance (PEC) of TiO2 NTAs was systematically investigated, and the optimal decoration of the CdS and PbS SQDs on the TiO2 NTAs was obtained. CdS/PbS co-sensitized TiO2 NTA photoanode films show excellent response to visible light (with absorption extended to 825 nm) and enhanced PEC performance. The best performing device showed an enhanced photocurrent density under the 0.62V vs SCE up to 8.2 mA/cm2, and high photoconversion efficiency up to 5.35%, which is 16.7 times higher than the pure TiO2 NTAs. The enhanced PEC performance of TiO2 NTAs is attributed to the co-sensitization, heterojunction formation and electron “pool” effect imparted on the NTAs by the coupling of CdS and PbS SQDs.

Hydrothermal growth of Bi2Ti2O7/TiO2 and Bi4Ti3O12/TiO2 heterostructures on highly ordered TiO2-nanotube arrays for dye-sensitized solar cells

Secure solar energy has been considered to be a possible way to alleviate the energy crisis. Using a hydrothermal reaction, functional heterostructures, including Bi2Ti2O7 and Bi4Ti3O12, were assembled on highly ordered TiO2-nanotube arrays that were prepared via a two-step anodic-oxidation method. The loading of the heterostructure onto the arrays was controlled by adapting the reaction temperature and alkalinity of the hydrothermal reaction. The samples were assembled into dye-sensitive solar cells to study their photoelectric performance. The optimal photoelectric-conversion efficiencies of Bi4Ti3O12/TiO2 (synthesized at 200 °C and pH 13.7) were 2.3 times greater than those of pure TiO2-nanotube arrays. The photoelectric property was enhanced due to the increase in the photoabsorption that originated from the introduction of the dyes, as well as the improvement in the charge-separation efficiency, which was derived from the matching of the energy-bands between the bismuth titanate and TiO2. The ferroelectric properties of Bi4Ti3O12 also played an important role in the enhanced photoelectric property.

Tuning the density distribution of deep localized states of TiO2 nanotube arrays through decoration with Pt and Pt@DLC

We demonstrate the possibility to tune the distribution of deep localized states and electronic transport properties of TiO2 nanotube arrays (TNA) through decoration its surface with Pt or Pt@DLC (Diamond-like carbon). A quantitative calculation of the position of the deep trap states in the band gap and the amount of accumulated charge in deep traps of Pt/TNA and Pt-DLC/TNA electrodes are presented and compared based on photocurrent-voltage curves. Our findings demonstrate that both Pt NPs and Pt@DLC depositions could decrease the quantity of deep localized states in the band gap by saturating the dangling bonds on the surface of TNA. A decline in photoluminescence intensity in platinized samples confirmed the density of deep trap states acting as recombination centers reduced by these surface modifications. Also, the deep localized states in Pt/TNA and Pt-DLC/TNA electrodes shift down towards valence band, in comparison with pure TNA. The neighborhood of the trapped electrons in deep states to the hole sites (VB) in platinized samples leads to the reduction of the electron- hole life time in these samples. Moreover, higher anodic photocurrent density was observed for pure TNA, revealed that in pure TNA the free photoexcited electrons reached to the conduction band will transport to the external circuit whereas, in Pt/TNAs and Pt-DLC/TNAs some free electrons would transfer to Pt NPs via Schottky junction at the semiconductor/electrolyte interface or via hopping or tunneling of pi-electrons existing in the sp2 nanoregions of DLC. Finally, Pt- and Pt@DLC-modified TNA electrodes absorbing light in the visible range and suppressing photoelectron recombination are worthy photocatalysts. In contrast, the deposition of Pt or Pt@DLC on TiO2 nanotubes resulted in lower PEC response.

Template synthesis and characterization of CdS/TiO2 coaxial nanocables for photocatalysis in visible light

CdS/TiO2 coaxial nanocables was synthesized through electrodeposition method with the assistant of porous anodic aluminum oxide (AAO) template. The obtained samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDX). The morphology results show that the external diameter of CdS/TiO2 coaxial nanocables is approximately 100 nm and the wall thickness is almost 20 nm, indicating that the TiO2 nanotubes are fully filled with CdS nanowires. The photo response shows that doping CdS nanowire arrays (NWAs) into TiO2 nanotube arrays (NTAs) could expand the spectral response of TiO2 from ultraviolet region to the visible light region. Meanwhile, compared with pure TiO2 NTAs, the CdS/TiO2 coaxial nanocables displayed an improved photodegradation efficiency for Rhodamine B (RhB) from 47.77 to 98.86%. As for the photocatalytic activity of hydrogen production, the H2 production evolution rate of CdS/TiO2 coaxial nanocables was 8.7 times higher than that of TiO2 NTAs within 200 min reaches as 1256 μmol/h. The enhancement of photocatalysis activity indicates that CdS/TiO2 coaxial nanocables has a potential application in photocatalytic field.

Enhancing Photocatalytic Activity on (MnO@TNTAs):Mn2+ with a Hierarchical Sandwich-Like Nanostructure via a Two-Step Procedure

Several semiconductor nanomaterial devices are increasingly being applied in a variety of fields, especially in the treating of environmental pollutants. We have fabricated (MnO@TNTAs):Mn2+ with sandwich-like nanostructures composed of TiO2 nanotube arrays (TNTAs), Mn-doped TNTAs and MnO. The experimental procedure was a two-step synthesis: first, using anodic oxidation methods and then hydrothermal methods. We carried out many characterizations of the “sandwiches“ in the nanoscale. From the field emission scanning electron microscopy images we found nanofibers lying on the highly-ordered nanotube arrays. The diameter of the nanotubes was about 50 nm but the size of the nanofibers varied. Energy dispersive spectroscopy demonstrated that the nanofibers contained a manganese element and x-ray diffraction patterns showed the peak of the manganosite phase. From ultraviolet–visible light spectra, it was found that the nanostructures had strong absorption activities under both ultraviolet and visible light radiation, while pure TNTAs had absorption only under ultraviolet light. The photodegradation experiments proved that the sandwich-like nanostructures had an excellent photocatalytic activity (92.5% after 240 min), which was a great improvement compared with pure TNTAs. In this way, the structures as a device at the nanoscale have a huge potential in controlling environmental pollution.

(Invited) Enhanced Photoelectrocatalytic Activity for Splitting Water Based on Heterostructured TiO2 Nanotube Arrays

Photoelectrocatalytic water splitting is widely recognized as one of the most promising strategies to large-scale production of hydrogen for renewable energy. To further enhance the photoelectrocatalytic efficiency, severalheterostructures based on TiO2 nanotube arrays were developed in this work. (1) TiO2 nanotube arrays (TNTAs) were decorated with NiO nanoparticles via a sequential chemical bath deposition (CBD) approach to yield NiO@TNTA photoanodes. It demonstrated that the incident-photon-to-current-conversion efficiency (IPCE) and hydrogen production rate of the optimized NiO@TNTA reached 62.8% and 37.8 μmol.h-1.cm-2, respectively, approximately 5.0 times higher than pure TNTAs, which was attributed primarily to the efficient separation of photogenerated charge carriers at the p–n junction of p-type NiO and n-type TiO2. (2) CuxZn1-xIn2S4 ultrathin nanosheets on TiO2 nanotube arrays (CZIS@TNTAs) was successfully synthesized by solvothermal reaction. It found that the CuxZn1-xIn2S4 ultrathin nanosheets on TNTAs significantly enhanced visible light absorption and and a near 8.0-fold increase in photoelectrocatalytic hydrogen production rate was achieved compared to that of the blank TNTAs. The superior photoelectrocatalytic activity of CZIS@TNTAs heterostructured composite electrode was mainly due to enhanced light absorption and separation of photo-generated charges, and facilitating electron transport along the 1D TiO2 structure. (3) TiO2 nanotube arrays (TNTAs) sensitized by palladium quantum dots (Pd QDs) by a modified hydrothermal reaction. When Pd@TNTA nanocomposites were used as both photoanode and cathode in water splitting, the photon-to-current conversion efficiency of nearly 100% atλ=330 nm and a greatly promoted photocatalytic hydrogen production rate of 592 μmol·h−1·cm−2 under 320 mW·cm−2 irradiation were achieved. The synergy between nanotubular structures of TiO2 and uniformly dispersed Pd QDs on TiO2 facilitated the charge transfer from TiO2 nanotubes to Pd QDs and the high activity of Pd QDs catalytic center, thereby leading to high-efficiency photoelectrocatalytic hydrogen generation.

Enhanced visible-light-active photocatalytic performances on Ag nanoparticles sensitized TiO2 nanotube arrays

TiO2 nanotube arrays (TNAs) synthesized using anodic oxidation method perform an excellent photocatalytic activity due to their unique tubular structure and large specific surface areas. Here, we reported a modified hybrid TiO2 nanostructure, Ag nanoparticles sensitized TiO2 nanotube arrays (Ag@TNAs), which were synthesized using classical anodic oxidation methods and special hydrothermal methods. Field emission scanning electron microscopy (FESEM) with energy dispersive spectroscopy (EDS) showed Ag nanoparticles were well-dispersed and anchored to the top surface of TNAs. X-Ray diffraction (XRD) showed the phases of anatase TiO2, silver and Ti substrate obviously. UV–vis absorption spectra performed an enhanced absorbance to visible light and photoluminescence (PL) performed a better optical property than pure TNAs. The photocatalytic performances of the as-synthesized Ag@TNAs were evaluated in terms of their photodegradation rate of methylene blue (MB) in an aqueous solution under light. The Ag@TNAs showed an enhanced photocatalytic activity compared with pure TNAs, and a probable photocatalytic mechanism was proposed.

Synthesis and Photocatalytic Properties of Ce-Doped TiO2 Nanotube Arrays via Anodic Oxidation

Ce-doped TiO2 nanotube arrays (TNAs) were prepared successfully through one-step anodic oxidation methods. The structural and morphological features of the TNAs were monitored by x-ray diffraction and field emission scanning electron microscopy with energy dispersive spectroscopy. Ultraviolet–visible light absorption spectra showed the light absorption performances of TiO2 nanotubes in both ultraviolet (UV) and visible light regions. Also, the photocatalytic activities of these samples were measured by the photodegradation rate of methylene blue (MB). The result indicated that doping a moderate amount of cerium ions into TNAs increased the absorption of both ultraviolet light and visible light obviously. However, the excess amount of doping ions would destroy the tubular structure severely and decrease the specific surface area of TNAs sharply. It could directly lead to the decreasing of photocatalytic activitity of TNAs. Furthermore, the best photodegradation rate of the Ce-doped TNAs on MB reached to 95.6%, which had a huge improvement comparing with pure TNAs.

Enhancement of electrochemical properties of micro/nano electrodes based on TiO2 nanotube arrays

Titanium oxide nanotube (TiO2 nanotube) arrays were produced by anodizing titanium foils in two different electrolytes. The first electrolyte consisted of ethylene glycol containing 0.5 wt% NH4F and 4 vol% of distilled water to produce pure TiO2 nanotube arrays and the second consisted of HF aqueous solution (0.5 wt%) containing 0.5% polyvinylalcohol to produce carbon doped TiO2 nanotube arrays. The fabricated TiO2 nanotube arrays were subsequently annealed in the atmosphere of nitrogen. The morphology and crystal structure of fabricated arrays were characterized by means of scanning electron microscopy and X-ray diffraction. The electrical conductivity and capacitance of TiO2 nanotube arrays were investigated by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). Water contact angle and biocompatibility of fabricated nanotube arrays were investigated. The results showed that carbon doped TiO2 nanotube arrays annealed in the atmosphere of nitrogen have higher conductivity and capacitance than those of pure arrays annealed in the same atmosphere. Doping with carbon enhances the biocompatibility and wettability of TiO2 nanotube arrays. It has also noted that electrical conductivity and capacitance of TiO2 nanotube arrays were directly proportional to the tube wall thickness.

5,10,15,20-tetrakis(4-chlorophenyl)porphyrin decorated TiO2 nanotube arrays: Composite photoelectrodes for visible photocurrent generation and simultaneous degradation of organic pollutant

The composite TiO2 nanotube arrays/5,10,15,20-tetrakis(4-chlorophenyl) porphyrin (H2TClPP-TNTs) photoelectrode with high visible light photoelectrochemical properties was prepared by a facile surface adsorption method. The morphology, composition and optical property of H2TClPP-TNTs photoelectrode was investigated by scanning electron microscopy, X-ray diffraction, FT-IR spectra, X-ray photoelectron spectroscopy and UV–vis diffuse reflectance spectroscopy. The sensitization of H2TClPP on TNTs significantly extended the visible light response, the as-prepared H2TClPP-TNTs photoelectrode exhibits excellent photoelectrochemical performance and photocatalytic activity. The photodegradation efficiency of rhodamine B by using H2TClPP-TNTs irradiated under visible light for 4h was up to 92.8%, which was higher than that of pure TiO2 nanotube arrays.

Fe3+-Doped TiO2 Nanotube Arrays on Ti-Fe Alloys for Enhanced Photoelectrocatalytic Activity

Highly ordered, vertically oriented Fe3+-doped TiO2 nanotube arrays (Fe-TNTs) were prepared on Ti-Fe alloy substrates with different Fe contents by the electrochemical anodization method. The as-prepared Fe-TNTs were characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and related electrochemical techniques. XPS results demonstrated that Fe3+ ions were successfully doped into TiO2 nanotubes. The photoelectrochemical activity of Fe-TNTs was compared with that of pure TiO2 nanotube arrays (TNTs). The results showed that Fe-TNTs grown on low concentration (0.5 wt %–1 wt % Fe) Ti-Fe alloys possessed higher photocurrent density than TNTs. The Fe-TNTs grown on Ti-Fe alloy containing 0.8 wt % Fe exhibited the highest photoelectrochemical activity and the photoelectrocatalytic degradation rate of methylene blue (MB) aqueous solution was significantly higher than that of TNTs.

The photocatalytic performance research of La2O3 modified TiO2 nanotube arrays

Since the environmental pollution is becoming more and more serious, TiO2 nanotube arrays, as a new kind of photocatalytic degradation materials have been widely researched and applied in our society. In order to enhance its photocatalytic performance, TiO2 nanotube arrays modified by La2O3 were successfully synthesized via an anodic oxidation method through dissolved La2O3 powder in the organic electrolyte. The photoelectron chemical performances of the composite nanotube arrays were characterized by FE-SEM, XRD, UV, and the photocatalytic activity was evaluated by photodegrading methylene blue which was treated as the target pollutants. The analytical results demonstrated that the La2O3 modified TiO2 nanotube arrays has a more significantly increased capability for photocatalytic properties than the pure TiO2 nanotube arrays, and the new concept was helpful to guide the synthesis of robust visible-light photocatalysts.

Ag-Doped TiO2Nanotube Arrays Composite Film as a Photoanode for Enhancing the Photoelectric Conversion Efficiency in DSSCs

A Ag-doped double-layer composite film with TiO2nanoparticles (P25) as the underlayer and TiO2nanotube (TNT) arrays with the Ag-doped nanoparticles as the overlayer was fabricated as the photoanode in dye-sensitized solar cells (DSSCs). Five different concentrations of Ag-doped TNT arrays photoelectrode were compared with the pure TNT arrays composite photoelectrode. It is found that the photoelectric conversion efficiency of the TNT arrays composite photoanode is gradually improved from 3.00% of the pure TNT arrays composite photoanode to 6.12% of the Ag-doped TNT arrays photoanode with the increasing of the doping concentration, reaching up to the maximum in the 0.04 mol/L AgNO3solution, and then slightly decreased to 5.43% after continuing to increase the doping concentration. The reason is mainly that the cluster structure of the Ag nanoparticles with large surface area contributes to dye adsorption and the Surface Plasmon Resonance Effect of the Ag nanoparticles improved the photocatalytic ability of the TNT arrays film.

Facile preparation of extremely photoactive boron-doped TiO 2 nanotubes arrays

Doping of TiO2 nanotube arrays with boron was realized via electrochemical treatment of as-anodized titania immersed in electrolyte containing boric acid. The photoactivity of doped and pure titania was examined by means of photoelectrochemical and photocatalytic response under UV–vis irradiation. The results showed that photocurrent density of B-TNTs is remarkably higher (7.5 times) than density of pure TiO2 nanotube arrays. Furthermore, the usage of doped samples as a catalytic material leads to a significant improvement in decomposition efficiency of methylene blue and in the efficient formation of hydroxyl radicals than is the case in the presence of titania.