One-step synthesis of ZnO nanowires on zinc foils and their photocatalytic properties

ZnO nanostructures with different morphologies have been grown on zinc foil substrate by a novel and facile hydrothermal method, without the assistance of any catalyst or template. The obtained ZnO samples are characterized by SEM, EDX, XRD, UV-visible and photoluminescence techniques. The resulting ZnO nanorod has a diameter of about 70-90 nm and the average length is estimated to be in the range of 0.5-2.0 μm. It is shown that the as-grown ZnO samples have a very good crystallinity. A comparison of the photocatalytic degradation of methyl orange with different ZnO shows that the photocatalytic properties of the ZnO nanostructures depend on the morphology of ZnO. The growth process of the ZnO nanorods is proposed based on the solid-liquid-solid mechanism

Photo-electrocatalytic activity of TiO2 nanotubes prepared with two-step anodization and treated under UV light irradiation

To improve the photo-catalytic degradation of salicylic acid, we reported the fabrication of ordered TiO2 nanotube arrays by a simple and effective two-step anodization method and then these TiO2 nanotubes treated in a methanol solution under UV light irradiation. The TiO2 nanotubes prepared in the two-step anodization process showed better photo-catalytic activity than TiO2 nanotubes prepared in one-step anodization process. Also, compared with TiO2 nanotubes without the UV pretreatment, the TiO2 nanotubes pretreated in a methanol solution under UV light irradiation exhibited significant enhancements in both photocurrent and activity. The treated TiO2 nanotubes exhibited a 5-fold enhancement in photocurrent and a 2.5-fold increase in the photo-catalytic degradation of salicylic acid. Also the effect of addition of persulfate and periodate on the photo-catalytic degradation of salicylic acid were investigated. The results showed that the degradation efficiency of salicylic acid increased with increasing persulfate and periodate concentrations. These treated TiO2 nanotubes are promising candidates for practical photochemical reactors

One-step synthesis of ZnO nanowires on zinc foils and their photocatalytic properties

686-691<span style="font-size:11.0pt;mso-bidi-font-size: 10.0pt;font-family:" times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";="" mso-ansi-language:en-gb;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="" lang="EN-GB">ZnO nanostructures with different morphologies have been grown on zinc foil substrate by a novel and facile hydrothermal method, without the assistance of any catalyst or template. The obtained ZnO samples are characterized by SEM, EDX, XRD, UV-visible and photoluminescence techniques. The resulting ZnO nanorod has a diameter of about 70-90 nm and the average length is estimated to be in the range of 0.5-2.0 μm. It is shown that the as-grown ZnO samples have a very good crystallinity. A comparison of the photocatalytic degradation of methyl orange with different ZnO shows that the photocatalytic properties of the ZnO nanostructures depend on the morphology of ZnO. The growth process of the ZnO nanorods is proposed based on the solid-liquid-solid mechanism.</span

Electrochemical preparation and characterization of polyaniline/ graphene quantum dot films to electro-oxidation of ascorbic acid

Polyaniline-Graphene Quantum Dot/gold nanoparticles (Au/PANI-GQD) films were prepared by tow step electrochemical process. At the first step, mixture of aniline and GQD was heated and refluxed then electopolymrization performed. At the second step goldâs nanoparticles were dispersed on the surface of PANI-GQD film from galvanostatic condition in the bath containing KAu(CN)2. The electrochemical behaviorand electro-catalytic activity of Au/PANI-GQD electrode werecharacterized by cyclic voltammetry. The morphology of the PANI-GQD film and gold coating on this electrode were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) respectively. Results indicated that gold nanoparticles were homogeneously dispersed on the surface of polyanilinefilm. The electro-oxidation of ascorbic acid is found to proceed more facile on Au/PANI-GQD electrode than on bare gold electrode. The irreversible oxidation current of ascorbic acid exhibits a linear dependence on the ascorbic acid concentration in the range of 1â5 mM

Photochemical deposition of silver on Fe2O3 nanotubes prepared by anodization and exploring their photoelectrochemical activity

Photochemical deposition of silver on Fe2O3 nanotubes prepared by anodization and exploring their photoelectrochemical activit

Photoelectrochemical Water Splitting and H₂ Generation Enhancement Using an Effective Surface Modification of W-Doped TiO₂ Nanotubes (WT) with Co-Deposition of Transition Metal Ions

W-doped TiO2 nanotube arrays (WT) were fabricated by in situ electrochemical anodization of titanium substrate. The results of the influence of different photo-deposited transition ions (CrxFe1−x, 0 ≤ x ≤ 1) on the surface of WT on photoelectrochemical (PEC) water splitting and H2 generation are presented. The crystallinities, structural, elemental, and absorption analysis were conducted by XRD, SEM, RAMAN, EDX, and UV–Vis absorption spectroscopy, which demonstrated anatase as the main crystalline phase of TiO2, and the existence of CrxFe1−x (nano)particles/film deposited on the surface of WT. The SEM images revealed that the deposition rate and morphology are highly related to the ratio of Cr and Fe ions. Under visible light illumination, the entire photoelectrodes showed a very good response to light with stable photocurrent density. PEC measurements revealed that the mixture of transition ions with a certain ratio of ions (Cr0.8Fe0.2–T) led to enhanced photocurrent density more than that of other modifiers due to decreasing charge recombination as well as improving the charge transfer. Moreover, PEC water splitting was conducted in an alkaline solution and the Cr0.8Fe0.2–T photoelectrode generated 0.85 mL cm−2 h−1 H2, which is over two times that of pristine WT

Photoelectrochemical Water Splitting and H2 Generation Enhancement Using an Effective Surface Modification of W-Doped TiO2 Nanotubes (WT) with Co-Deposition of Transition Metal Ions

W-doped TiO2 nanotube arrays (WT) were fabricated by in situ electrochemical anodization of titanium substrate. The results of the influence of different photo-deposited transition ions (CrxFe1&minus;x, 0 &le; x &le; 1) on the surface of WT on photoelectrochemical (PEC) water splitting and H2 generation are presented. The crystallinities, structural, elemental, and absorption analysis were conducted by XRD, SEM, RAMAN, EDX, and UV&ndash;Vis absorption spectroscopy, which demonstrated anatase as the main crystalline phase of TiO2, and the existence of CrxFe1&minus;x (nano)particles/film deposited on the surface of WT. The SEM images revealed that the deposition rate and morphology are highly related to the ratio of Cr and Fe ions. Under visible light illumination, the entire photoelectrodes showed a very good response to light with stable photocurrent density. PEC measurements revealed that the mixture of transition ions with a certain ratio of ions (Cr0.8Fe0.2&ndash;T) led to enhanced photocurrent density more than that of other modifiers due to decreasing charge recombination as well as improving the charge transfer. Moreover, PEC water splitting was conducted in an alkaline solution and the Cr0.8Fe0.2&ndash;T photoelectrode generated 0.85 mL cm&minus;2 h&minus;1 H2, which is over two times that of pristine WT