- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Enhancing visible light photocatalytic performance with N-doped TiO <sub/>2</sub> nanotube arrays assisted by H <sub/>2</sub> O <sub/>2</sub>
摘要： N-doped TiO2 nanotube arrays were prepared by an electrochemical anodization method and subsequent ammonia annealing. Microstructures, morphology, optical properties and photocatalytic properties of the N-doped TiO2 nanotube arrays were measured and analyzed. In the degradation of Acid Orange II(AO-II), the photocatalytic degradation efficiency of the N-doped TiO2 nanotube arrays assisted by H2O2 are 12 times, 2 times and 5 times higher than TiO2 nanotube arrays, TiO2 nanotube arrays assisted by H2O2 and H2O2, respectively. Experimental results show that the N-doped TiO2 nanotube arrays is a promising photocatalytic material for organic pollutant degradation under visible light, especially under the assistance of H2O2.
关键词： photocatalytic performance.,N-doped TiO2,H2O2,Electrochemical anodization
更新于2025-09-23 15:23:52
-
AIP Conference Proceedings [Author(s) 3RD INTERNATIONAL SCIENCES, TECHNOLOGY & ENGINEERING CONFERENCE (ISTEC) 2018 - MATERIAL CHEMISTRY - Penang, Malaysia (17–18 April 2018)] - Synthesis of gold nanoparticles (AuNPs) onto anodized titania nanotubes (TNTs) by spin coating technique
摘要： Gold nanoparticles (AuNPs) have received copious interests due to their unique properties such as small in size, reactive, high surface area and can be potentially applied in myriad fields including physics, chemistry, medicine and material sciences. However, the nanosized of gold particles makes them very reactive and undergo aggregation without protection. For that reason, supporting materials are introduced to prevent the aggregation of the AuNPs. In particular, metal oxide for example, titanium dioxide or titania nanotubes (TNTs) has been used as a support material because of its inertness, high porosity and great surface areas. Nevertheless, achieving precise control of attachment AuNPs on the TNTs substrate by conventional methods such as thermal evaporation and conservative heating are far from satisfactory. Herein, in this work, a new approach has been developed to synthesize controlled and uniformed attachment of AuNPs onto fabricated electrochemically-anodized TNTs by a spin coating technique. This preliminary work used different spin rate of 500, 1000 and 2000 revolutions per minute (rpm), following by heat treatment at 250 °C for 2 hours. The FESEM micrograph showed the anodized TNTs with good morphological structures were successfully fabricated at a voltage of 50 V in a mixture of ethylene glycol containing 0.5 wt. % ammonium fluoride solution, with an average nanotubes diameter of 150 nm. Meanwhile, the attachment of AuNPs on the fabricated TNTs has been effectively achieved at a higher spin rate of 2000 rpm and the EDX analysis confirmed the deposition of AuNPs over the TNTs. The AuNPs-TNTs also were tested for the catalytic reduction of p-nitrophenol (p-NP), in which is discussed shortly in this paper.
关键词： Gold nanoparticles,spin coating,titania nanotubes,electrochemical anodization
更新于2025-09-23 15:21:01
-
Electrolyte Factors Influencing Separated Pore Growth of Anodic TiO2 Nanotube Arrays
摘要： This work presents an investigation of electrolyte properties in relation to the growth of TiO2 nanotube array films, particularly concerning the measurement of conductivity in the diethylene glycol-hydrofluoric-water electrolyte system. The work aims to elucidate the behavior of ions in the anodized electrolytes with a better insight into the relation between molar conductivity and concentration of the additives. Differing solvation of the fluoride ion in various composition of water in the DEG-H2O mixture is attributed to the major factor determining the capability of proton transfer, controlling the ionic mobilities and the molar conductivities. Applying the feature of the two-factorial experiment has demonstrated a clear interaction of electrolyte parameters and titanium concentration dissolving into the electrolyte, which is believed to be a combination effect on pore widening and separating of nanotubes. A proposed schematic drawing has been demonstrated, summarizing how the nanotube arrays are constructed as a consequence of varying electrolyte type and composition.
关键词： electrochemical anodization,tube separation,TiO2 nanotube arrays,electrolyte conductivity
更新于2025-09-04 15:30:14
-
Enhanced Visible Light Sensitization of N-doped TiO2 Nanotubes Containing Ti-Oxynitride Species Fabricated via Electrochemical Anodization of Titanium Nitride
摘要： The concentration and chemical state of nitrogen represent critical factors to control the band-gap narrowing and the enhancement of visible light harvesting in nitrogen-doped titanium dioxide. In this study, photocatalytic TiO2-N nanoporous structures were fabricated by the electrochemical anodization of titanium nitride sputtered films. Doping was straightforwardly obtained by oxidizing as-sputtered titanium nitride films containing N-metal bonds varying from 7.3 to 18.5 % in the Ti matrix. Severe morphological variations into the as-anodized substrates were registered at different nitrogen concentration and studied by Small-Angle X-ray Scattering. Titanium nitride films with minimum N content of 6.2 at% N led to a quasi-nanotubular geometry, whilst an increase in N concentration up to 23.8 at% determined an inhomogeneous, polydispersed distribution of nanotube apertures. The chemical state of nitrogen in the TiO2 matrix was investigated by X-ray Photoelectron Spectroscopy depth profile analysis and correlated to the photocatalytic performance. The presence of Ti-N and β-Ti substitutional bonds, as well as Ti-oxynitride species was revealed by the analysis of N 1s X-ray Photoelectron Spectroscopy High Resolution spectra. The minimum N content of 4.1 at% in the TiO2-N corresponded to the lowest Ti-oxynitride ratio of 13.5 %. The relative variation of N-metal bonds was correlated to the visible light sensitization and the highest Ti-N/Ti oxynitride ratio of 3.3 was attributed to the lowest band-gap of 2.7 eV and associated to a threefold increase in the degradation of organic dye. Further increase of N doping led to a dramatic drop of Ti-N/Ti oxynitride ratio, from 3.3 to 0.4, which resulted in a loss photocatalytic activity. The impact of the chemical state of nitrogen towards efficient doping of TiO2 nanotubes is demonstrated with a direct correlation to the N loading and a strategy to optimise these factors based on a simple, rapid synthesis from titanium nitride.
关键词： visible light sensitization,photocatalytic performance,titanium nitride,nitrogen-doped titanium dioxide,electrochemical anodization
更新于2025-09-04 15:30:14