Azeotropic distillation, ethanol washing, and freeze drying on coprecipitated gels for production of high surface area 3Y–TZP and 8YSZ powders: A comparative study

Piva, Roger Honorato; Piva, D.H.; Pierri, J. J.; Montedo, Oscar Rubem Klegues; Morelli, M. R.

doi:10.1016/j.ceramint.2015.07.037

Cited by 20 publications

(8 citation statements)

References 61 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The specific surface-area values of the samples dehydrated by EW/AD were considerably higher than those obtained after FD in agreement with a previous work 43 . Practically the same S BET values were achieved for 9InTaSZ and 9InNbSZ, whereas the Nb 2 O 5 and Ta 2 O 5 oxides can be considered as having similar effects in the gel formation during coprecipitation.…”

Section: Powder Characteristics After Dehydrationsupporting

confidence: 92%

Synthesis by coprecipitation of india-stabilized zirconia and codoping with MoO3, WO3, TaO2.5, or NbO2.5 for application as thermal barrier coatings

Piva

Morelli

2016

Mat. Res.

View full text Add to dashboard Cite

Coprecipitation synthesis of nanocrystalline india-stabilized zirconia with high surface area and codoping with MoO 3 , WO 3 , TaO 2.5 , or NbO 2.5 is reported. The concentration of codopants was defined by the charge-compensating mechanism. Ethanol washing followed by azeotropic distillation and freeze drying were compared as dehydration techniques for the gels. As determined by XRD and Raman scattering, 9 mol% of InO 1.5 plus charge-compensating dopants is sufficient to completely stabilize the high-temperature tetragonal phase of zirconia. The effect of alloying hexavalent and pentavalent oxides was secondary compared to the InO 1.5 concentration in the retention of the tetragonal structure. Improved specific surface area of 106.1 m 2 g -1 and crystallite size between 8 and 9 nm were achieved through ethanol washing and subsequent azeotropic distillation even after calcination at 600 ºC. This result is attributed to the effect of the incorporation of ethoxy and butoxy groups after the treatment of the gels in organic medium, as detected by FT-IR spectroscopy and DSC/TG.

show abstract

Section: Powder Characteristics After Dehydrationsupporting

confidence: 92%

Synthesis by coprecipitation of india-stabilized zirconia and codoping with MoO3, WO3, TaO2.5, or NbO2.5 for application as thermal barrier coatings

Piva

Morelli

2016

Mat. Res.

View full text Add to dashboard Cite

show abstract

“…The overall stirring period prior to filtering was ~2 h. The pH of the solution obtained was adjusted during stirring using an ammonia solution (25%; Labochemie, India) to form a white precipitate in a slightly acidic medium (pH 6.0–6.5) using a pH meter (Adwa, Romania). The precipitate was vacuum filtered using qualitative filter paper (45 μ, 12 cm; Double Rings, China) via a Buchner funnel, washed three times with deionized water and washed another three times with ethanol to reduce the possibility of agglomeration (Patil et al , 2012; Piva et al , 2015; Lu et al , 2020), after which it was placed upon a watch glass and dried at 40°C overnight in a drying oven (ED53/E2; Binder, Germany).…”

Section: Methodsmentioning

confidence: 99%

Effects of the full-scale substitution of strontium for calcium on the microstructure of brushite: (Ca_xSr_1–x)HPO₄.nH₂O system

et al. 2020

View full text Add to dashboard Cite

Brushite (CaHPO4.2H2O) is an important calcium phosphate encountered in bone tissue engineering and bone cement formulation. There are many studies on the synthesis and characterization of brushite, but full-scale substitution and replacement of Ca by Sr in brushite as a key element in medical and environmental applications has not yet been explored systematically. Therefore, this study aims to evaluate the effects of substitution of Ca by Sr on the microstructural and thermal properties of brushite, including the chemical phases present, crystallization, structural water and phase stability. The chemical phases were determined by means of powder X-ray diffraction. The thermal properties were studied by thermogravimetric analysis. Crystallization and surface morphology were analysed using scanning electron microscopy. Various properties were dependent on the incorporated Sr ions. The replacement percentage of Sr may be divided into two major stages: the first from 0% to 50%; and the second from 50% up to 100%. The (Ca x Sr1–x)HPO4.nH2O shows that micro-scale crystals of platy brushite formed in the first stage of Sr replacement, from 0% up to 50%. As Sr might inhibit the formation of crystals, crystal nucleation rates were reduced as the Sr percentage increased. An amorphous product formed as a result of 50% Sr replacement. The second stage of Sr replacement with Sr contents >50% yielded a new crystal morphology corresponding mainly to SrHPO4.nH2O. The complete replacement of Ca by Sr transforms the brushite with platy microcrystals into SrHPO4 nanosheets.

show abstract

“…The aim was to obtain a white precipitate that was then vacuum filtered using a Buchner funnel and a qualitative filter paper (45 µm, ∅12 cm, Double Rings, Shanghai, China). The filter cake was first washed three times with deionized water, which was followed by three washes in ethanol to prevent agglomeration [26][27][28]. Finally, the sample was placed on a watch glass and was left to dry in an oven set at 40 • C for one week (ED53/E2, Binder, Tuttlingen, Germany) [29].…”

Section: Of 12mentioning

confidence: 99%

The Impact of Full-Scale Substitution of Ca2+ with Ni2+ Ions on Brushite’s Crystal Structure and Phase Composition

et al. 2022

View full text Add to dashboard Cite

Because the impact of the full-scale substitution of Ca2+ in brushite (CaHPO4·2H2O) with Ni2+ ions has never been systematically explored, it is the focus of this investigation, as it holds potential for use in CaxNi1−xHPO4·nH2O production. These biomaterials have many beneficial characteristics that can be modified to suit diverse applications, including bone tissue regeneration and pharmaceutics. For the present study, NaH2PO4·2H2O, Ca(NO3)2·4H2O, and Ni(NO3)2·6H2O were used in various molar concentrations to obtain the required starting solutions. Previous studies have shown that adding Ni ions in the initial solution below 20% results in the precipitation of monophasic brushite with slight changes in the crystal structure. However, this study confirms that when the Ni ions substitution increases to 20%, a mixture of phases from both brushite and hexaaquanickel(II) hydrogenphosphate monohydrate HNiP (Ni(H2O)6·HPO4·H2O) is formed. The results confirm that the full replacement (100%) of Ca ions by Ni ions results in a monophasic compound solely comprising orthorhombic HNiP nanocrystals. Therefore, a novel technique of HNiP synthesis using the precipitation method is introduced in this research work. These materials are subsequently analyzed utilizing powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The obtained results confirm that the material microstructure is controlled by the Ni/Ca ratio in the starting solution and can be modified to obtain the desired characteristics of phases and crystals.

show abstract

Azeotropic distillation, ethanol washing, and freeze drying on coprecipitated gels for production of high surface area 3Y–TZP and 8YSZ powders: A comparative study

Cited by 20 publications

References 61 publications

Synthesis by coprecipitation of india-stabilized zirconia and codoping with MoO3, WO3, TaO2.5, or NbO2.5 for application as thermal barrier coatings

Synthesis by coprecipitation of india-stabilized zirconia and codoping with MoO3, WO3, TaO2.5, or NbO2.5 for application as thermal barrier coatings

Effects of the full-scale substitution of strontium for calcium on the microstructure of brushite: (Ca_xSr_1–x)HPO₄.nH₂O system

The Impact of Full-Scale Substitution of Ca2+ with Ni2+ Ions on Brushite’s Crystal Structure and Phase Composition

Contact Info

Product

Resources

About

Azeotropic distillation, ethanol washing, and freeze drying on coprecipitated gels for production of high surface area 3Y–TZP and 8YSZ powders: A comparative study

Cited by 20 publications

References 61 publications

Synthesis by coprecipitation of india-stabilized zirconia and codoping with MoO3, WO3, TaO2.5, or NbO2.5 for application as thermal barrier coatings

Synthesis by coprecipitation of india-stabilized zirconia and codoping with MoO3, WO3, TaO2.5, or NbO2.5 for application as thermal barrier coatings

Effects of the full-scale substitution of strontium for calcium on the microstructure of brushite: (CaxSr1–x)HPO4.nH2O system

The Impact of Full-Scale Substitution of Ca2+ with Ni2+ Ions on Brushite’s Crystal Structure and Phase Composition

Contact Info

Product

Resources

About

Effects of the full-scale substitution of strontium for calcium on the microstructure of brushite: (Ca_xSr_1–x)HPO₄.nH₂O system