Application of statistical methodology for the evaluation of mechanically activated phase transformation in nanocrystalline TiO2

Rezaee, Masih; Khoie, S.M. Mousavi; Haghshenas, Davoud Fatmehsari; Liu, Huan

doi:10.1016/j.jallcom.2011.06.015

Cited by 11 publications

(7 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The high pressure, being dominant at the particle surface during collisions, favored the formation of high pressure TiO 2 II. Rezaee et al 544 concluded that increasing the milling time has no signicant effect on the phase transformation, while the milling speed and powder to ball ratio is the most effective factor in tuning the phase transition. For a given collision time, an increase in the powder to ball ratio leads to a higher energy release for each particle.…”

Section: Preparation Of Tio 2 From Ball Milling (Mechanochemical Acti...mentioning

confidence: 99%

See 1 more Smart Citation

Polymorphic phase transition among the titania crystal structures using a solution-based approach: from precursor chemistry to nucleation process

2014

View full text Add to dashboard Cite

Nanocrystalline titania are a robust candidate for various functional applications owing to its non-toxicity, cheap availability, ease of preparation and exceptional photochemical as well as thermal stability. The uniqueness in each lattice structure of titania leads to multifaceted physico-chemical and opto-electronic properties, which yield different functionalities and thus influence their performances in various green energy applications. The high temperature treatment for crystallizing titania triggers inevitable particle growth and the destruction of delicate nanostructural features. Thus, the preparation of crystalline titania with tunable phase/particle size/morphology at low to moderate temperatures using a solution-based approach has paved the way for further exciting areas of research. In this focused review, titania synthesis from hydrothermal/solvothermal method, conventional sol-gel method and sol-gel-assisted method via ultrasonication, photoillumination and ILs, thermolysis and microemulsion routes are discussed. These wet chemical methods have broader visibility, since multiple reaction parameters, such as precursor chemistry, surfactants, chelating agents, solvents, mineralizer, pH of the solution, aging time, reaction temperature/time, inorganic electrolytes, can be easily manipulated to tune the final physical structure. This review sheds light on the stabilization/phase transformation pathways of titania polymorphs like anatase, rutile, brookite and TiO2(B) under a variety of reaction conditions. The driving force for crystallization arising from complex species in solution coupled with pH of the solution and ion species facilitating the orientation of octahedral resulting in a crystalline phase are reviewed in detail. In addition to titanium halide/alkoxide, the nucleation of titania from other precursors like peroxo and layered titanates are also discussed. The non-aqueous route and ball milling-induced titania transformation is briefly outlined; moreover, the lacunae in understanding the concepts and future prospects in this exciting field are suggested.

show abstract

Section: Preparation Of Tio 2 From Ball Milling (Mechanochemical Acti...mentioning

confidence: 99%

“…This results in excess microstructural defects such as dislocations and vacancies. 537,544,545 Alternatively, it is very likely that the microstructural changes in the milling speed reduce the microstructural diffusion path lengths, which accelerate the phase transformation kinetics.…”

Section: Preparation Of Tio 2 From Ball Milling (Mechanochemical Acti...mentioning

confidence: 99%

Polymorphic phase transition among the titania crystal structures using a solution-based approach: from precursor chemistry to nucleation process

2014

View full text Add to dashboard Cite

show abstract

“…Anatase TiO 2 was reported to transform by high-energy ball-milling into rutile via this α-PbO 2 type modification, for any constituting materials of milling tools and for any ball-mill. 45,46,[82][83][84][85][86][87][88][89][90][91][92][93][94][95] It is worth noticing that the structures of anatase and of rutile can be transformed into that of TiO 2 II by shear. 96 The Rietveld method 97 was used to determine the volume fractions of anatase, TiO 2 -II and rutile from XRD patterns as a function of milling time t m (Fig.…”

Section: Phase Transformations In Titania Induced By Grindingmentioning

confidence: 99%

“…3). 84,85,90,92,93,95,98 For starting titania powders, which may differ by their amounts of anatase and/or by their average particle sizes, the anatase volume fraction in ball-milled TiO 2 decreases with t m , that of rutile increases while that of TiO 2 -II goes through a maximum for t m = t M . Thus two reactions occur consecutively: anatase → TiO 2 -II → rutile.…”

Section: Phase Transformations In Titania Induced By Grindingmentioning

confidence: 99%

Transformations in oxides induced by high-energy ball-milling

2012

View full text Add to dashboard Cite

This paper, by no means exhaustive, focuses on high-energy ball-milling of oxides, on their mechanically induced changes and on the consequences of such changes on their physical and chemical properties. High-energy ball-milling offers a fortunate combination of technical simplicity and of complexity both of physical mechanisms which act during milling and of mechanosynthesized materials. Its basic interest, which stems from the large diversity of routes it offers to prepare oxides either directly or indirectly, is illustrated with various families of oxides. The direct path is to be favoured when as-milled oxides are of interest per se because of their nanocrystalline characteristics, their defects or their modified structures which result from mechanically driven phase transformations. The indirect path consists of a sequence of steps starting with mechanically activated oxides which may be subsequently just annealed or submitted to a combination of thermal treatments, with the possible occurrence of various chemical reactions, to prepare the sought-after materials with potential gains in processing temperatures and times. High energy ball-milling of oxides is more and more currently used to activate powders and to prepare nano-oxides at moderate temperatures. The interest of an activation step is well illustrated by the broad development of doped titania powders, synthesized by heat treatment of pre-ground reactants, for photocatalytic applications or to develop antibacterial materials. Another important class of applications of high-energy ball-milling is the formation of composites. It is exemplified here with the case of oxide-dispersed strengthened alloys whose properties are considerably improved by a dispersion of ultra-stable nanosized oxides whose formation mechanisms were recently described. The basic understanding of the mechanisms by which oxides or oxide mixtures evolve by high-energy ball-milling appears to be less advanced than it is for metallic materials essentially because of the overall complexity of the oxide structures, of their surfaces, of their defects and of their mechanical behavior.

show abstract

“…The only methodology capable of providing an answer to this question is factorial design of experiments (DOEs), whichthrough the use of techniques such as response surface methodology (RSM) -is able to simultaneously consider several factors at different levels, and give a suitable model for the relationship between the various factors and the response [38]. However, RSM has been applied in only one case to a ball milling system [39].…”

Section: Modelmentioning

confidence: 99%

Evaluation of strengthening behavior of Al–AlN nanostructured composite by the use of modified Heckel model and response surface methodology

Farnoush

Haghshenas

Mohandesi

et al. 2012

Journal of Alloys and Compounds

View full text Add to dashboard Cite

Application of statistical methodology for the evaluation of mechanically activated phase transformation in nanocrystalline TiO2

Cited by 11 publications

References 37 publications

Polymorphic phase transition among the titania crystal structures using a solution-based approach: from precursor chemistry to nucleation process

Polymorphic phase transition among the titania crystal structures using a solution-based approach: from precursor chemistry to nucleation process

Transformations in oxides induced by high-energy ball-milling

Evaluation of strengthening behavior of Al–AlN nanostructured composite by the use of modified Heckel model and response surface methodology

Contact Info

Product

Resources

About