Exceptional behavior of anatase TiO2 nanotubes in axial loading: A molecular dynamics study of the effect of surface wrinkles

The scope of this work shows novel experimental findings on preparing anatase TiO2 nanoparticles, first anodizing titanium into an organic media for obtaining TiO2 nanotubes, and using these as a photocatalytic active electrode in treating water polluted with organic contaminants. The substrates were grit blasted to obtain mechanical fixation of the generated nanotubular TiO2 structure. This was successfully achieved without diminishment of the nanotubes order and with a self-leveling of the outer surface. A new phenomenon has been investigated consisting of the process of oxidation of the nanotubes in water after anodizing. Along this process, methyl orange added to the aqueous solution was discolored as part of the redox reaction involved. The final state of the modified layer was composed of conglomerates of almost completely crystalline TiO2 nanoparticles, around 4 nm in size, consisting of anatase. SEM and TEM images show the transition of the amorphous nanotubes (atomic disorder/nanometric order) to crystalline disordered particles (atomic order/nanometric disorder).

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Enhanced photocatalytic bacterial inactivation of atomic-layer deposited anatase-TiO2 thin films on rutile-TiO2 nanotubes

Photochemical & Photobiological Sciences ◽

10.1039/c9pp00348g ◽

2020 ◽

Vol 19 (3) ◽

pp. 399-405

Author(s):

Joel Molina-Reyes ◽

Alejandra Romero-Morán ◽

José L. Sánchez-Salas

Keyword(s):

Thin Films ◽

Photocatalytic Activity ◽

Tio2 Nanotubes ◽

Considerable Increase ◽

Atomic Layer ◽

Surface Modifications ◽

Anatase Tio2 ◽

Bacterial Inactivation ◽

Tio2 Thin Films ◽

Experimental Conditions

Experimental conditions to fabricate rutile-TiO2 nanotubes coated with a conformal anatase-TiO2 thin layer using ALD were reported. A considerable increase in the photocatalytic activity associated with these surface modifications was also observed.

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Molecular Dynamics Studies on the Effect of Surface Roughness and Surface Tension on the Thermodynamics and Dynamics of Hydronium Ion Transfer Across the Liquid/Liquid Interface

The Journal of Physical Chemistry B ◽

10.1021/acs.jpcb.0c06304 ◽

2020 ◽

Vol 124 (39) ◽

pp. 8711-8718

Author(s):

Ilan Benjamin

Keyword(s):

Molecular Dynamics ◽

Surface Tension ◽

Surface Roughness ◽

Liquid Interface ◽

Ion Transfer ◽

Hydronium Ion ◽

Thermodynamics And Dynamics ◽

Effect Of Surface

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Molecular Dynamics Study of Anatase TiO2 Nanoparticles in Water and Vacuum Environments

Volume 8: Mechanics of Solids, Structures and Fluids ◽

10.1115/imece2012-87712 ◽

2012 ◽

Author(s):

George Okeke ◽

Robert B. Hammond ◽

S. Joseph Antony

Keyword(s):

Molecular Dynamics ◽

Surface Tension ◽

Surface Energy ◽

Tio2 Nanoparticles ◽

Anatase Tio2 ◽

Particle Sizes ◽

Metallic Oxides ◽

Wide Range ◽

Enhanced Properties ◽

Dynamics Simulations

Nanoparticles are nanometer sized metallic oxides which possess enhanced properties that are desirable to a wide range of industries. In this study, we investigate structural and surface properties of anatase TiO2 nanoparticles in vacuum and water environments using molecular dynamics simulations. The particle sizes ranged from 2 to 6 nm and simulations were performed at 300 K. Surface energy of the particles in vacuum was seen to be higher than that of the particles in water by about 100% for the smaller particles (i.e. 2 and 3nm) and about 60% for the larger particles (i.e. 4 to 6 nm). Surface energy of the particles in both environments, is seen to increase to a maximum (optimum value) as the particle size increases after which no further significant increase is observed. In vacuum, studies carried out at temperatures ranging from 300–2500 K showed a high dependence of surface energy on temperature. The estimated surface tension of water is seen to agree quite well with that of experiments.

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