Anatase-to-rutile transition in co-doped TiO2 pigments

Giraldi, Tania R.; Dias, Jeferson Almeida; Baggio, Carly Mirela; Maestrelli, Sylma Carvalho; Oliveira, Jéssica A.

doi:10.1007/s10971-017-4379-y

Cited by 16 publications

(10 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Recently, the ART of cobalt doped TiO2 (Co-TiO2) was studied at a single calcination temperature of 600 °C and a dopant (Co) concentration in the range of 0 % to 4 mol % 36 . The results revealed that ART of TiO2 was promoted by Co doping.…”

mentioning

confidence: 99%

Indium-Doped TiO₂ Photocatalysts with High-Temperature Anatase Stability

et al. 2019

View full text Add to dashboard Cite

The thermal stability of anatase titanium dioxide (TiO2) is a prerequisite to fabricate photocatalyst coated indoor building materials for use in antimicrobial and self-cleaning applications under normal room light illumination. Metal doping of TiO2 is an appropriate way to control the anatase to rutile phase transition (ART) at high processing temperature. In this present work, ART of indium (In) doped TiO2 (In-TiO2) was investigated in detail in the range of 500 °C -900 °C. In-TiO2 (In mol % = 0 to 16) was synthesized via a modified solgel approach. These nanoparticles were further characterized by means of powder X-ray diffraction (XRD), Raman, photoluminescence (PL), transient photocurrent response, and Xray photoelectron spectroscopy (XPS) techniques. XRD results showed that the anatase phase was maintained up to 64 % by 16-mol % of In doping at 800 °C of calcination temperature.XPS results revealed that the binding energies of Ti 4+ (Ti 2p1/2 and Ti 2p3/2) were red-shifted by In doping. The influence of In doping on the electronic structure and oxygen vacancy formation of anatase TiO2 was studied using density functional theory corrected for on-site Coulomb interactions (DFT+U). First principles results showed that the charge compensating oxygen vacancies form spontaneously at sites adjacent to the In dopant. DFT+U calculations revealed the formation of In -5s states in the band gap of the anatase host. The formation of In2O3 at the anatase surface was also examined using a slab model of the anatase (101)

show abstract

mentioning

confidence: 99%

Indium-Doped TiO₂ Photocatalysts with High-Temperature Anatase Stability

et al. 2019

View full text Add to dashboard Cite

show abstract

“…The red shift is a result of Ti ions being imbedded in Ce surrounding, thus affecting the Ti2p binding energy. [77][78][79] As such, the resulting DSC spectra show more than one exothermic events, corresponding of a primary event resulted from the initial coarsening of the nano-powder that followed by a relatively minor event (initiates ~900°C) when the coarsening restrictions are lifted. 28,31,73 With these processes in mind, the DSC spectra can now be revisited, and the minor peaks that are present can be explored.…”

Section: Discussionmentioning

confidence: 99%

“…Ti-doped samples, on the other hand, display a "broken" process, resulting from the anatase-rutile phase transformation which is an exothermic event with a typical onset of 900°C. [77][78][79] As such, the resulting DSC spectra show more than one exothermic events, corresponding of a primary event resulted from the initial coarsening of the nano-powder that followed by a relatively minor event (initiates ~900°C) when the coarsening restrictions are lifted. It is important to note that the peak magnitude (height and area) does not directly reflect on crystallite size or the rate of coarsening, rather, is related to the amount of energy released in the process.…”

Section: Discussionmentioning

confidence: 99%

Thermal stability of nano Ce_1−xTi_xO₂material system for X < 0.2

2019

View full text Add to dashboard Cite

Ceria (CeO2) is a technologically promising compound due to a remarkable set of properties. However, the use of ceria also has drawbacks, the most pronounced of which is the material's poor thermal stability. This property limits the use of ceria‐based materials at elevated temperatures, in many technological applications. To overcome this, the addition of TiO2 is proposed. Such addition essentially creates a new material system, namely Ce1−xTixO2. In this work, an array of techniques were employed to determine the thermal stability of this new compound range (X < 0.2). Results show that when nano‐sized, TiO2 is fully soluble in CeO2 in this range. After heat treatment, however, the material coarsens and the solubility limit decreases to less than 2 at.%. as the compound undergoes significant changes. These include solute segregation and phase separation. Finally, the factors that affect compound stability are discussed.

show abstract

“…Já o TiO 2 -PP apresenta baixa área superficial, 0,56 m 2 g -1 . Isto é característico do método de síntese (GIRALDI et al, 2017), uma vez que a alta temperatura de tratamento térmico promove a aglomeração das partículas e consequentemente a diminuição da área de superfície.…”

Section: Amostraunclassified

Características Fisico-Químicas De Nanoparticulas De Tio2 Obtidas Por Diferentes Métodos De Síntese

Maldi¹,

Freschi²,

Moreira³

et al. 2019

Blucher Chemical Engineering Proceedings

View full text Add to dashboard Cite

RESUMO-Diferentes métodos de sínteses (Percursores Poliméricos (PP), hidrotermal assistido em radiação micro-ondas (MW) e sonoquímico (US) foram aplicados para obtenção do semicondutor TiO 2 .As suas características físicoquímicas se mostraram influenciadas pelo método de síntese aplicado, evidenciando que por meio dos métodos MW e US, a fase fotoativa do TiO 2 (Anatase) é preferencialmente obtida. Os diâmetros de partícula variaram de 25 a 90 nm, a carga superficial (potencial zeta) variaram de-2,2 mV à 23,0 mV. Palavras-chave: Nanomateriais. Métodos de síntese. Caracterização físicoquímica.

show abstract

Anatase-to-rutile transition in co-doped TiO2 pigments

Cited by 16 publications

References 17 publications

Indium-Doped TiO₂ Photocatalysts with High-Temperature Anatase Stability

Indium-Doped TiO₂ Photocatalysts with High-Temperature Anatase Stability

Thermal stability of nano Ce_1−xTi_xO₂material system for X < 0.2

Características Fisico-Químicas De Nanoparticulas De Tio2 Obtidas Por Diferentes Métodos De Síntese

Contact Info

Product

Resources

About

Anatase-to-rutile transition in co-doped TiO2 pigments

Cited by 16 publications

References 17 publications

Indium-Doped TiO2 Photocatalysts with High-Temperature Anatase Stability

Indium-Doped TiO2 Photocatalysts with High-Temperature Anatase Stability

Thermal stability of nano Ce1−xTixO2 material system for X < 0.2

Características Fisico-Químicas De Nanoparticulas De Tio2 Obtidas Por Diferentes Métodos De Síntese

Contact Info

Product

Resources

About

Indium-Doped TiO₂ Photocatalysts with High-Temperature Anatase Stability

Indium-Doped TiO₂ Photocatalysts with High-Temperature Anatase Stability

Thermal stability of nano Ce_1−xTi_xO₂material system for X < 0.2