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Resistance gene expression and microbial inhibition by halogenated antibiotics is a major environmental concern. Although electrocatalytic dehalogenation can detoxify halogenated antibiotics, the effect of dehalogenation treatment on resistance gene expression and microbial inhibition is poorly understood. Herein, a novel electrocatalyst of Fe-doped CoP nanotubes array on nickel foam (Fe-CoP NTs/NiF) is prepared through a simple ultrasonication of Fe-doped CoP nanowires hydrothermally grown on NiF. The transformation from nanowires to nanotubes improves the crystallinity of CoP and fully exposes active sites, producing energetic atomic hydrogen for dehalogenation. Fe-CoP NTs/NiF exhibits a superior dehalogenation performance towards refractory florfenicol (FLO), achieving 100% removal within 20 min (‒1.2 V vs Ag/AgCl, C 0  = 20 mg L ‒1 ). The dechlorination ratio reaches nearly 100%, and the defluorination ratio achieves 36.8% within 50 min, showing the best electrocatalytic dehalogenation performance reported so far. Microbial community and correlation analysis show that Proteobacteria is the main potential host of FLO resistance gene. Electrocatalytic reductive dehalogenation pretreatment of FLO can reduce microbial inhibition, maintaining microbial richness and diversity in the subsequent biochemical treatment unit. The electrocatalytic reductive dehalogenation treatment can significantly reduce the relative abundance of FLO resistance gene, showing a reliable process for safe treatment of halogenated antibiotic containing wastewater., (Copyright © 2021. Published by Elsevier Ltd.)

TiO2 nano-materials have been considered as a versatile candidate for the photoelectrochemical (PECH) applications. In this study, we reported a facile and novel strategy to synthesize reduced TiO2 nanotubes (TiO2 NTs) photoelectrode. The microwave reduction could introduce oxygen vacancy in the lattice of TiO2, while the rapid-production of oxygen vacancy facilitated the generation of impurity level between the forbidden band and greatly enhancement of visible light absorption, thereby resulting in an improved separation efficiency of photogenerated charge carriers and photocatalytic (PC) performance. Additionally, the derived valence band X-ray photoelectron spectroscopy (VBXPS) and photoluminescence (PL) spectra confirmed the existence of oxygen vacancy in the lattice of TiO2 NTs photoelectrode, in which the valence bond maximum (VBM) and charge carriers concentration of reduced TiO2 NTs photoelectrode was determined to be 1.75 eV and 5.36 × 10(19) cm(-3), respectively. Furthermore, the scavenging experiments revealed that ·OH radical was the dominated species for the degradation of diclofenac. The enhanced-visible-light PC mechanism could mainly be attributed to the generation of oxygen vacancy, which can provide not only the visible light absorption capacity but also charge separation efficiency., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

TiO2 has been considered as a versatile candidate for the photoelectrochemical (PECH) application. In this study, Pd nano-crystallite decorated TiO₂ nano-tubes (Pd/TNTs) photoelectrode was prepared through electrochemical deposition. The resulting Pd/TNTs samples were characterized by SEM, XRD, DRS and XPS. It was found that the decorated Pd nano-crystallite existed in the form of Pd(0) with an average diameter of 30 nm, and could improve the light absorption in visible region. In addition, PECH properties of Pd/TNTs photoanode were investigated through transient open circuit potential, photocurrent response, electro-chemical impedance spectroscopy (EIS) and Mott-Schottky analysis. Moreover, the generation rate of hydroxyl radicals (•OH) was detected by a photoluminescence (PL) spectra using terephthalic acid (TA) as a probe molecule. Results showed that Pd/TNTs photoelectrode exhibited high transient photoinduced current of 0.094 mA cm(-2), open circuit photovoltage of -0.339 mV cm(-2) and effective photoelectrocatalytic (PEC) efficiency of 67.7% (0.4V vs. SCE) for the degradation of diclofenac (DCF). The high PC and PEC efficiency could mainly be attributed to the decoration of Pd nano-crystallite which could provide pathway for the transfer of photoinduced charge carriers. Furthermore, the contribution of series of active species was applied to clarify the enhanced PC mechanism., (Copyright © 2013 Elsevier B.V. All rights reserved.)

In this research Ag2Mn8O16 nanocrystals/TiO2 nanotubes, photoelectrodes were successfully prepared through anodization and annihilation steps, followed by electrodeposition of MnO2 and Ag in a three electrodes cell. The obtained photoelectrodes were dried, then annealed for crystallization, the morphology and structure of the fabricated electrodes were characterized via scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The light absorption and harvesting properties were investigated through UV–visible diffuse reflectance spectrum (DRS), photocatalytic performances were evaluated by degradation of 50 mL of Rhodamine B (5 mg L−1) under Xenon light irradiation for 2 h. Results illustrated that the fabricated photoelectrodes show remarkable photo-degradation properties of organic pollutants in aqueous mediums.

W-doped/undoped TiO2 nanotube array (TNAs) photoelectrodes with different nanostructures were successfully fabricated using the anodization method. Their morphology and characteristics were studied using scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and ultra violet/visible light diffuse reflectance spectra (UV/vis/DRS). Their electronic structure and optical properties were studied by means of first-principle. Photocatalytic (PC) performance of W-TNAs photoelectrodes with different crystal structures was evaluated using the decomposition rates of Rhodamine B (Rh.B) under xenon light illumination. The results demonstrated that W substituting Ti broadened the width of conduction band (CB) and valence band (VB) of anatase and rutile TiO2, reduced the band gap of rutile TiO2 and even caused its red-shift. W incorporated into TNAs photoelectrodes extended light absorption threshold and enhanced its utilization of solar light and PC activity, particularly, the PC performance of W-TNAs photoelectrodes with mixed crystal and rutile crystal structure. [ABSTRACT FROM AUTHOR]

Abstract In this research Ag2Mn8O16 nanocrystals/TiO2 nanotubes, photoelectrodes were successfully prepared through anodization and annihilation steps, followed by electrodeposition of MnO2 and Ag in a three electrodes cell. The obtained photoelectrodes were dried, then annealed for crystallization, the morphology and structure of the fabricated electrodes were characterized via scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The light absorption and harvesting properties were investigated through UV–visible diffuse reflectance spectrum (DRS), photocatalytic performances were evaluated by degradation of 50 mL of Rhodamine B (5 mg L−1) under Xenon light irradiation for 2 h. Results illustrated that the fabricated photoelectrodes show remarkable photo-degradation properties of organic pollutants in aqueous mediums. [ABSTRACT FROM AUTHOR]

Pd-MnO 2 /TiO 2 nanotube arrays (NTAs) photo-electrodes were successfully fabricated via anodization and electro deposition subsequently; the obtained Pd-MnO 2 /TiO 2 NTAs photo electrodes were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD) and characterized accordingly. Moreover, the light harvesting and absorption properties were investigated via ultraviolet–visible diffuse reflectance spectrum (DRS); photo degradation efficiency was investigated via analyzing the photo catalytic degradation of Rhodamine B under visible illumination (xenon light). The performed analyses illustrated that Pd-MnO 2 codoped particles were successfully deposited onto the surface of the TiO 2 nanotube arrays; DRS results showed significant improvement in visible light absorption which was between 400 and 700 nm. Finally, the photo catalytic degradation efficiency results of the designated organic pollutant (Rhodamine B) illustrated a superior photocatalytic (PC) efficiency of approximately 95% compared to the bare TiO 2 NTAs, which only exhibited a photo catalytic degradation efficiency of approximately 61%, thus it indicated the significant enhancement of the light absorption properties of fabricated photo electrodes and their yield of OH radicals. [ABSTRACT FROM AUTHOR]

Abstract: Graphene film decorated TiO2 nano-tube array (GF/TiO2 NTA) photoelectrodes were prepared through anodization, followed by electrodeposition strategy. Morphologies and structures of the resulting GF/TiO2 NTA samples were characterized by scanning electrons microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Raman spectroscopy. In addition, the optical and photoelectrochemical properties were investigated through UV–visible light diffuse reflection spectroscopy, photocurrent response and Mott–Schottky analysis. Furthermore, the photodecomposition performances were investigated through yield of hydroxyl radicals and photocatalytic (PC) degradation of methyl blue (MB) under visible light irradiation. It was found that GF/TiO2 NTA photoelectrode exhibited intense light absorption both in UV light and visible region, higher transient photoinduced current of 0.107mAcm−2 and charge carrier concentration of 0.84×1019 cm−3, as well as effective PC performance of 65.9% for the degradation of MB. Furthermore, contribution of several reactive species to the PC efficiency of GF/TiO2 NTA photoelectrode was distinguished. Moreover, the enhanced visible light PC mechanism was proposed and confirmed in detail. [Copyright &y& Elsevier]

Abstract: In this study, TiO2 nano-particles decorated TiO2 nano-tubes arrays (TiO2 NPs/TiO2 NTAs) photoelectrodes have been successfully prepared through anodization, combined with ultrasonic strategy, followed by annealing post-treatment. The morphology and structure of the as-prepared TiO2 NPs/TiO2 NTAs photoelectrodes were characterized by scanning electrons microscopy (SEM), N2 adsorption/desorption isotherms, X-ray diffraction (XRD) and UV–visible light diffuse reflection spectroscopy (DRS). In addition, the generation of hydroxyl radicals ( OH) was detected by a photoluminescence (PL) spectra using terephthalic acid (TA) as a probe molecule. Furthermore, the photoelectrochemical (PECH) properties of TiO2 NPs/TiO2 NTAs photoanode were investigated through transient open circuit potential (OCP), photocurrent response (PCR) and electrochemical impedance spectroscopy (EIS). It was found that TiO2 NPs/TiO2 NTAs photoelectrode exhibited a distinct decrease of OCP of −0.219mVcm−2 and PCR of 0.049mAcm−2, while a significantly enhanced photoelectrocatalytic (PEC) efficiency of 63.6% (0.4V vs. SCE) for the degradation of diclofenac. Moreover, the enhanced PEC mechanism of TiO2 NPs/TiO2 NTAs photoanode was proposed. The high PEC performance could be attributed to the decoration of TiO2 NPs, which could improve the mobility and separation efficiency of photoinduced charge carriers under external potential. [Copyright &y& Elsevier]

Abstract: TiO2/Ti Nanotube arrays (TNAs) and WO3/TNAs photoelectrodes were fabricated by in situ anodization and cycle pulse electrochemical deposition method. The morphology and structure were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectra and X-ray photoelectron spectroscopy (XPS). Optical properties and photoelectrochemical (PECH) properties were investigated by surface photovoltage (SPV), ultra UV–vis diffuse reflectance spectra (UV/vis/DRS), open-circuit potential (OCP), and photocurrent density The results showed that WO3/TNAs photoelectrodes have excellent photoresponse performance. WO3 would enhance the photovoltage and photocurrent of TNAs photoelectrodes. The presence of WO3 caused red shift and enhanced the photosensitivity of TNAs photoelectrodes in whole light region. [Copyright &y& Elsevier]

Highlights: [•] Pd/TNTs photoelectrodes have been prepared through electrochemical deposition method. [•] The role of Pd on the enhancement of PC and PEC performance has been investigated. [•] Contribution of series of active species on the degradation of diclofenac has been investigated. [•] The enhanced PC mechanism of Pd/TNTs photoelectrode was proposed. [ABSTRACT FROM AUTHOR]

Abstract: TiO2/Ti Nanotube array (TNTa) photoelectrodes were prepared by galvanostatic and potentiostatic anodization technique, and annealed at different temperature. The morphology and structure were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman spectra. Optical properties and photoelectrochemical (PECH) properties were investigated by surface photovoltage (SPV), ultra UV–vis diffuse reflectance spectra (UV/vis/DRS), open-circuit potential (OCP) and transient photocurrent. Photodecomposition performances were evaluated by the yield of •OH radicals and photocatalytic (PC) degradation rate of 4-nonylphenol (4-NP) under xenon light. The results showed that with the increase of post-treatment temperature, PECH and PC properties increased gradually and then decreased. The photocurrent densities, yield of ⁎OH radicals and photodecomposition rates of 4-NP were following the trend of TNT-823>TNT-873>TNT-773>TNT-673>TNT-973>TNT-298. When the annealing temperature was 823K, the photoelectrodes were composed of mixed crystal structure and ordered nanotube array, which exhibited superior PECH properties. When the annealed temperature arrived to 973K, the nanotube collapsed and the PECH and PC properties of TNTa photoelectrodes decreased. For TNT-823 photoelectrodes, after the assistant potential was applied, the degradation rate of 4-NP increased significantly from 77% to 97% after 120min illumination. [Copyright &y& Elsevier]

Abstract: Wormhole-shaped TiO2/Ti (WT) and nanotube-shaped TiO2/Ti (TNT) photoelectrodes were prepared by anodic oxidation method. The morphology and structure were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). It was found that both crystal types of WT and TNT photoelectrodes were composed of anatase and rutile TiO2 phases; however TNT photoelectrodes had highly ordered nanostructure. The photoelectrochemical (PECH) and photoelectrocatalytic (PEC) properties of WT and TNT photoelectrodes were investigated by photocurrent transient, open-circuit potential and degradation rate of alachlor under the artificial solar light illumination. All results showed that TNT photoelectrodes prepared in NaF–Na2SO4 solution have more excellent photoelectron properties than WT photoelectrodes prepared in H2SO4 solution. The photocatalytic (PC) and PEC experiments of alachlor showed that PC and PEC activities of TNT photoelectrodes were superior to WT photoelectrodes. At applied bias potentials the degradation rate of alachlor at TNT photoelectrodes increased significantly to 94.5%. The higher PC and PEC performance of TNT photoelectrodes were ascribed to the long-range ordered structure and short-orientation diffusion distance of photogenerated carries. [Copyright &y& Elsevier]

In the present work, narrow band gap Ag 2 S nano-crystallites decorated TiO 2 nanotubes arrays (Ag 2 S NCs/TiO 2 NTAs) photoelectrode was successfully constructed through anodization, followed by successive ionic layer adsorption and reaction (SILAR) strategy. Subsequently, morphologies and chemical structures were investigated through scanning electron microscope (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). In addition, the optical and photoelectrochemical (PECH) properties were recorded through Ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS), transient photocurrent density and Mott-Schottky measurements. Furthermore, the photocatalytic (PC) performance was evaluated through the yield of hydroxyl (·OH) radicals and degradation of methyl blue under visible light illumination. All results indicated that Ag 2 S NCs/TiO 2 NTAs photoelectrode exhibited intense visible light absorbance, high transient photocurrent of 0.098 mA · cm −2 and charge carrier concentration of 1.58 × 10 19 · cm −3 , as well as effective PC performance of 83.6% for the degradation of methyl blue. Besides, · OH radicals was the dominated responsible active species during the PC process. The enhanced visible light PC performance was mainly attributed to the intense visible light absorbance and high charge carrier separation efficiency. [ABSTRACT FROM AUTHOR]

In order to improve the separation efficiency of photogenerated charge carriers and photocatalytic (PC) performance of TiO 2 nanotubes (TiO 2 NTs) photoelectrode, Pd nanoparticles and reduced graphene oxide co-modified TiO 2 NTs (Pd-RGO/TiO 2 NTs) photoelectrode was fabricated through two-step electro-deposition in this study. Subsequently, physicochemical properties of the resulting samples were investigated through SEM, XRD, XPS and Raman techniques. Additionally, the generation of OH was detected by fluorescence spectra using terephthalic acid as the probing molecule. Furthermore, the photoelectrochemical properties of Pd-RGO/TiO 2 NTs photoelectrode were studied through UV–vis DRS, photocurrent density and electrochemical impedance spectroscopy. As a result, Pd-RGO/TiO 2 NTs photoelectrode exhibited a significantly enhanced photocurrent density of 0.111 mA cm −2 and charge carrier concentration of 1.43 × 10 19 cm −3 , as well as efficient PC performance of 58.4% for the degradation of diclofenac aqueous solution. Moreover, the enhanced-PC mechanism was proposed. The efficient visible PC performance of Pd-RGO/TiO 2 NTs photoelectrode could mainly be attributed to the co-modification of Pd and RGO species, which could not only improve the light harvesting property, but also the effective separation of photogenerated charge carriers. Furthermore, the enhanced PC mechanism for degradation of diclofenac was proposed and confirmed. This study provides an effective strategy to fabricate TiO 2 NTs-based photoelectrode which could be applied in the fields of organic pollutants elimination and wastewater treatment. [ABSTRACT FROM AUTHOR]