A comparative study on the photocatalytic activities of microporous and nanoporous TiO2 layers prepared by electrochemical anodization

Dikici, Tuncay; Yıldırım, Serdar; Yurddaşkal, Metin; Erol, Mustafa; Yiğit, Recep; Toparlı, Mustafa; Çelik, Erdal

doi:10.1016/j.surfcoat.2014.12.076

Cited by 26 publications

(17 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Anatase and rutile phase ratios were calculated using the Spurr equation, and the results are shown in Table . The results are consistent with the studies in the literature . In summary, it was observed that anatase phase transformed into rutile phase, the most stable structure of TiO 2 , with increasing anodisation potential; thus, rutile phase density increased.…”

Section: Resultssupporting

confidence: 86%

Tribocorrosion behaviour of porous anatase and rutile phases formed on surface of anodised Ti45Nb alloy

Taşdemir

Alsaran

2020

Lubrication Science

View full text Add to dashboard Cite

Titanium alloys are used across a wide range of sectors—from aerospace to health—because of their low density, high strength, and corrosion resistance properties. In recent years, the use of alloying elements such as niobium (Nb), tantalum (Ta), and zirconium (Zr) has still not eliminated existing wear problems, in spite of being preferred to conventional titanium alloys that are non‐toxic and have better corrosion and mechanical properties. In order to overcome this problem of titanium alloys, various surface treatments are applied. This study was mainly aimed at investigating tribocorrosion properties of anatase, rutile, and anatase‐rutile phases formed on the surface of Ti45Nb by anodising at different potential values. The structural and mechanical properties of these structures were examined by X‐ray diffraction (XRD), scanning electron microscopy (SEM), energy‐dispersive spectroscopy (EDS), nanoindentation, and a 3D profilometer. Tribocorrosion tests were carried out at open‐circuit potential (OCP) and two different anodic in NaCl solutions. It was found that the wear volume was affected by mechanical action rather than chemical effects for all samples during tribocorrosion. It was concluded that while a surface structure including anatase is more sensitive to chemical effects, the rutile structures were shown to be more resistant to both mechanical and chemical attacks during tribocorrosion tests.

show abstract

Section: Resultssupporting

confidence: 86%

Tribocorrosion behaviour of porous anatase and rutile phases formed on surface of anodised Ti45Nb alloy

Taşdemir

Alsaran

2020

Lubrication Science

View full text Add to dashboard Cite

show abstract

“…The photocatalytic parameters of the samples were given in Table 1. The film annealed at 600 o C proved to be the best photocatalyst among the samples annealed from 500 o C to 800 o C. The photocatalytic activity of TiO2 structures depends on several factors such as surface area, crystallinity, phase composition and crystal orientation [Dikici et al, 2015].…”

Section: Resultsmentioning

confidence: 99%

EFFECT OF ANNEALING TEMPERATURES ON THE CRYSTALLIZATION AND PHOTOCATALYTIC ACTIVITY OF MICRO-NANOPOROUS TiO2 FILMS PRODUCED BY ELECTROCHEMICAL ANODIZATION

Yurddaşkal¹,

Yurddaşkal²,

Dikici³

et al. 2017

Journal of the Turkish Chemical Society, Section A: Chemistry

Self Cite

View full text Add to dashboard Cite

ABSTRACT:In this study, micro-nanoporous TiO2 films were prepared by electrochemical anodization of titanium (Gr-2) in an aqueous solution containing 0.5 wt. % HF solution at a constant potential of 30 V and then annealed in ambient air at 500, 600, 700 and 800 C for 2 h to obtain crystalline structures. The crystalline phase and surface morphology of the samples were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The photocatalytic performances of the samples were evaluated by the photocatalytic degradation of aqueous methylene blue (MB) solutions under UV light illumination for different periods. XRD results indicated that at annealing temperatures higher than 600°C, anatase started to transform into rutile. Increasing annealing temperatures resulted in reduced micro-nanopores diameter and increased wall thickness. At 800C, the structure completely disappeared. The results demonstrated that changes in both the crystalline structure and surface morphology have a strong influence on the photoactivity of the nanostructured TiO2 films.

show abstract

“…It is known that this rotation during OAD gives rise to a microstructure formed by vertical nanocolumns. , Figure shows a schematic representation of the deposition setup and the typical nanocolumn structure formation induced with this procedure. More detailed information about the preparation and properties of single layers of these materials can be found in refs − , − . All samples were annealed at 400 °C in air for 3 h to induce the crystallization of the titania layers into the photocatalytically active anatase phase (a-TiO 2 ) of this oxide.…”

Section: Methodsmentioning

confidence: 99%

“…These nanostructured multilayered systems have been manufactured by electron beam evaporation in an oblique angle configuration (OAD), , a procedure known to render columnar thin films with empty volume ratios up to 50%. We and other laboratories have applied this procedure to the fabrication of single photocatalytic layers of TiO 2 and other materials − or the fabrication of dye-sensitized solar cells. , …”

Section: Introductionmentioning

confidence: 99%

Titania Enhanced Photocatalysis and Dye Giant Absorption in Nanoporous 1D Bragg Microcavities

Rico

Turk

Yubero

et al. 2022

ACS Appl. Nano Mater.

View full text Add to dashboard Cite

Light trapping effects are known to boost the photocatalytic degradation of organic molecules in 3D photonic structures of anatase titania (a-TiO 2 ) with an inverse opal configuration. In the present work, we show that photocatalytic activity can also be enhanced in a-TiO 2 thin films if they are incorporated within a nanoporous 1D optical resonant microcavity. We have designed and manufactured multilayer systems that, presenting a high open porosity to enable a straightforward diffusion of photodegradable molecules, provide light confinement effects at wavelengths around the absorption edge of photoactive a-TiO 2 . In brief, we have observed that a nanoporous 1D Bragg microcavity prepared by electron beam evaporation at oblique angles comprising a central defect layer of nanoporous a-TiO 2 boosts the photocatalytic degradation of nitrobenzene and methyl orange dye solutions. The multilayer structure of the microcavity was designed to ensure the appearance of optical resonances at the a-TiO 2 layer location and wavelengths around the absorption onset of this semiconductor. In this porous 1D Bragg microcavity, the diffusion constraints of molecules through the capping layers covering the a-TiO 2 are effectively compensated by an increase in the photocatalytic activity due to the light confinement phenomena. We also report that the absorption coefficient of methyl orange dye solution infiltrated within the pore structure of the microcavity is exalted at the wavelengths of the corresponding optical resonances. This effect gives rise to a small but non-negligible visible light photodegradation of dye molecules. The possibilities of tailoring the design of 1D photonic systems to boost the photocatalytic activity of a-TiO 2 are discussed.

show abstract

A comparative study on the photocatalytic activities of microporous and nanoporous TiO2 layers prepared by electrochemical anodization

Cited by 26 publications

References 35 publications

Tribocorrosion behaviour of porous anatase and rutile phases formed on surface of anodised Ti45Nb alloy

Tribocorrosion behaviour of porous anatase and rutile phases formed on surface of anodised Ti45Nb alloy

EFFECT OF ANNEALING TEMPERATURES ON THE CRYSTALLIZATION AND PHOTOCATALYTIC ACTIVITY OF MICRO-NANOPOROUS TiO2 FILMS PRODUCED BY ELECTROCHEMICAL ANODIZATION

Titania Enhanced Photocatalysis and Dye Giant Absorption in Nanoporous 1D Bragg Microcavities

Contact Info

Product

Resources

About