In Situ Probing of Photoinduced Hydrophilicity on Titania Surface Using Dye Molecules

This communication uses EQCM in combination with the potentiostatic method to study the in situ exchange mechanism for dye molecules and cations on the nano-film surface under a constant potential.

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Correlation of the Photocatalytic Activities of Cu, Ce and/or Pt-Modified Titania Particles with their Bulk and Surface Structures Studied by Reversed Double-Beam Photoacoustic Spectroscopy

Catalysts ◽

10.3390/catal9121010 ◽

2019 ◽

Vol 9 (12) ◽

pp. 1010 ◽

Cited By ~ 1

Author(s):

Preeya Unwiset ◽

Guangyi Chen ◽

Bunsho Ohtani ◽

Kingkaew Chayakul Chanapattharapol

Keyword(s):

Photoacoustic Spectroscopy ◽

Sol Gel ◽

Aerobic Condition ◽

Lower Activity ◽

Platinum Deposition ◽

Ce Modification ◽

Double Beam ◽

Photocatalytic Activities ◽

Titania Surface

Modified titania photocatalyst powder samples were prepared using the sol-gel method for copper (Cu) and cerium (Ce) doping and impregnation for platinum (Pt) loading. Their bulk crystalline structures were investigated using X-ray diffractometry (XRD) with the Rietveld analysis. The surface/bulk structure, surface properties, and morphologies were observed using reversed double-beam photoacoustic spectroscopy (RDB-PAS), nitrogen adsorption, and scanning electron microscopy, respectively. The results from the XRD revealed that all samples were mainly anatase (ca. 80% or higher) with small amounts of rutile and non-crystalline components. The specific surface areas of all samples were in the range of 115–155 m2 g−1. Ce and Cu species were mainly distributed, while Pt was potentially loaded as a partially oxidized form on the titania surface. The results from the RDB-PAS indicated the changing of the energy-resolved distribution of electron traps (ERDT) from the original titania surface upon doping of the metals (Cu, Ce, and Pt), which altered their catalytic activities. The metals photocatalytic activities with UV irradiation were measured in two representative reactions; (a) CO2 evolution from acetic acid under the aerobic condition and (b) H2 evolution from deaerated aqueous methanol. In reaction (a), the Cu and/or Ce modification gave almost the same or slightly lower activity compared to the non-modified titania samples, while platinum loading yielded ca. 5–6 times higher activity. For reaction (b), the photocatalytic tests were divided into two sets; without (b1) and with (b2) Pt deposition during the reaction. Similar enhancements of activity from the Pt loading sample (and by Cu modification) were observed in reaction (b1) without in-situ platinum deposition, while the unmodified and Ce-doped samples were almost inactive. For the activities of reaction (b2) with in-situ platinum deposition, the unmodified samples showed the highest activity while the Cu-modified samples showed significantly lower activity.

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In situ iron-57 Mössbauer spectroscopic investigations of the effect of titania surface area on the reducibility of titania-supported iron oxide

Hyperfine Interactions ◽

10.1007/bf02405716 ◽

1990 ◽

Vol 57 (1-4) ◽

pp. 1747-1751 ◽

Cited By ~ 1

Author(s):

Frank J. Berry ◽

DU Hongzhang

Keyword(s):

Iron Oxide ◽

Surface Area ◽

Spectroscopic Investigations ◽

Titania Surface ◽

Supported Iron

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Advanced Synthesis and Characterization of Vanadia/Titania Catalysts through a Molecular Approach

Catalysts ◽

10.3390/catal11030322 ◽

2021 ◽

Vol 11 (3) ◽

pp. 322

Author(s):

Eleni Tella ◽

Antonios Trimpalis ◽

Athanasios Tsevis ◽

Christos Kordulis ◽

Alexis Lycourghiotis ◽

...

Keyword(s):

Raman Spectroscopy ◽

Temperature Dependent ◽

In Situ Raman Spectroscopy ◽

Monomeric Species ◽

Synthesis Conditions ◽

In Situ Raman ◽

Titania Surface ◽

Inner Sphere

Vanadia/titania catalysts were synthesized by the equilibrium deposition filtration (EDF) method, which is a synthesis route that follows a molecular-level approach. The type of interfacial deposition as well as the interfacial speciation of the deposited oxo-V(V) species were determined by means of a model that takes into account experimental “proton-ion” curves and “adsorption edges”. It is shown that at pH ≥ 9.5, the deposition proceeds exclusively through the formation of mono-substituted inner sphere monomeric species in an “umbrella”-like Ti–OV(OH)2O configuration, whilst with lowering of the pH, a second species, namely the disubstituted inner sphere quadrameric species in a (Ti-O)2V4O10 configuration possessing two mono-oxo V=O and two di-oxo V(=O)2 terminations gradually prevails, which is in co-existence with the monomeric species. Raman spectroscopy is used for verifying the solution speciation, which is different compared to the interfacial speciation of the deposited oxo-V(V) species. Furthermore, in situ Raman spectroscopy was used to verify the model-predicted interfacial speciation of the deposited oxo-V(V) species and to monitor the temperature-dependent evolution up to 430 °C. Hence, a controlled formation of a specific vanadia species on a titania surface is enabled, which, depending on the synthesis conditions, can result in specific catalyst characteristics and thus possibly different catalytic behavior for a specific reaction.

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In Situ Mapping of the Molecular Arrangement of Amphiphilic Dye Molecules at the TiO2 Surface of Dye-Sensitized Solar Cells

ACS Applied Materials & Interfaces ◽

10.1021/acsami.5b01638 ◽

2015 ◽

Vol 7 (20) ◽

pp. 10834-10842 ◽

Cited By ~ 25

Author(s):

Kislon Voïtchovsky ◽

Negar Ashari-Astani ◽

Ivano Tavernelli ◽

Nicolas Tétreault ◽

Ursula Rothlisberger ◽

...

Keyword(s):

Solar Cells ◽

Dye Sensitized Solar Cells ◽

Tio2 Surface ◽

Dye Molecules ◽

Dye Sensitized ◽

Molecular Arrangement ◽

Sensitized Solar Cells

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Microscopic observation of dye molecules for solar cells on a titania surface

Scientific Reports ◽

10.1038/srep24616 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 4

Author(s):

Shogo Koshiya ◽

Shunsuke Yamashita ◽

Koji Kimoto

Keyword(s):

Solar Cells ◽

Microscopic Observation ◽

Dye Molecules ◽

Titania Surface

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In Situ Synthesis of Magnetic Poly(DMAEAB-co-NIPAm)@Fe3O4 Composite Hydrogel for Removal of Dye from Water

Gels ◽

10.3390/gels7040201 ◽

2021 ◽

Vol 7 (4) ◽

pp. 201

Author(s):

Zhi Chen ◽

Xia Song ◽

Wilson Wee Mia Soh ◽

Yuting Wen ◽

Jingling Zhu ◽

...

Keyword(s):

Removal Efficiency ◽

Physical Adsorption ◽

Dye Adsorption ◽

In Situ Synthesis ◽

Composite Hydrogel ◽

Bromophenol Blue ◽

Magnetic Composite ◽

Dye Molecules ◽

Magnetic Hydrogel

Water pollution by toxic substances, such as dye molecules, remains a major environmental problem that needs to be solved. In the present work, the magnetic composite hydrogel based on the poly(2-(methacryloyloxy)-N-(2-hydroxyethyl)-N,N-dimethylethan-1-aminium bromide-co-N-isopropylacrylamide) copolymer with incorporated Fe3O4 particles ((poly(DMAEAB-co-NIPAm)@Fe3O4)) was prepared by an in situ synthesis technique for the efficient removal of dye molecules from water. The successfully synthesized magnetic hydrogel was characterized by FTIR, XRD, TGA, and TEM. The removal efficiency of the anionic dye bromophenol blue (BPB) and the cationic dye rhodamine B (RDM) by the prepared hydrogel adsorbents was evaluated. Various adsorption parameters, including the concentration of adsorbents and adsorption time, were also investigated. The results showed that the synthesized magnetic hydrogel had excellent BPB removal performance compared to the removal of RDM. The optimum adsorbent concentration for 0.5 mM BPB solution was approximately 0.5 g/L, and the removal efficiency was more than 99%. The kinetics data of BPB removal fitted well into the pseudo-2nd-order model, indicating that BPB dye adsorption involves chemical adsorption and physical adsorption. In addition, recycling studies were conducted to examine the reusability of the magnetic hydrogel for BPB removal for up to five cycles and the hydrogel could be reused without losing its high removal efficiency. The magnetic hydrogel poly(DMAEAB-co-NIPAm)@Fe3O4 with high removal efficiency, good selectivity, and reusability shows great potential for the removal of anionic dyes in wastewater treatment.

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Kinetics of in situ desorption of dye molecules on sensitized TiO2 nanoparticles in a high concentration solution: ion parasitic adsorption process and mass reference

Physical Chemistry Chemical Physics ◽

10.1039/c8cp03059f ◽

2018 ◽

Vol 20 (32) ◽

pp. 20856-20862 ◽

Cited By ~ 2

Author(s):

Weiqing Liu ◽

Fei Liu ◽

Yujing Liu ◽

Yuqian Ai

Keyword(s):

Tio2 Nanoparticles ◽

Adsorption Process ◽

Mass Change ◽

Dye Molecules ◽

High Concentration ◽

Desorption Process ◽

Dye Sensitized ◽

High Concentration Solution ◽

Kinetics Of

This paper applies a method to study the in situ mass change responses on dye-sensitized TiO2 films in different potential ranges, and explore the dye desorption process in depth and in detail.

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