Comparative study of nanocrystalline zirconia prepared by precipitation and sol–gel methods

Wang, Jinan; Valenzuela, Miguel A.; Salmones, J.; Espinoza-Vázquez, Araceli; Garcı́a-Ruiz, A.; Bokhimi, Xim

doi:10.1016/s0920-5861(01)00319-4

Cited by 130 publications

(76 citation statements)

References 21 publications

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“…In Figure 2, diffractograms of sulfated zirconia and 2% Fepromoted sulfated zirconia (FeSZi) are presented; the narrow reflections in these patterns originate from an internal creasing treatment temperature [58][59][60][61][62] when initially amorphous material is calcined, and this is reproduced in our results. In comparison of unpromoted and promoted SZ, the presence of Fe or Mn clearly reduces the amount of monoclinic phase that is formed during calcination at 923 K. Figure 3 shows the results of refinement of the lattice constants of tetragonal zirconia (P4 2 /nmc) to the XRD data; specifically the unit cell volume of the tetragonal phase is plotted vs. the promoter content.…”

Section: X-ray Diffractionsupporting

confidence: 64%

Incorporation of manganese and iron into the zirconia lattice in promoted sulfated zirconia catalysts

Jentoft

Hahn

Kröhnert

et al. 2004

Journal of Catalysis

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Two series of Mn-or Fe-promoted zirconia samples were prepared, (i) a series of sulfated-free reference compounds via co-precipitation of aqueous solutions containing zirconium and the promoter cation, and (ii) a series of catalysts via incipient-wetness impregnation of a sulfated zirconium hydroxide. The promoter content was varied between 0 and 5 wt% metal. All promoter-containing materials were calcined at 923 K. The reference materials contained mainly isolated Mn or Fe species incorporated into the zirconia lattice as evidenced by stabilization of the tetragonal zirconia phase, EPR (isolated ions in highly symmetric environment), and a shrinking unit cell volume (XRD) of the tetragonal zirconia phase with increasing promoter content. Only the Mn-promoted catalysts showed such shrinkage in unit cell volume with increasing promoter content. At 2 wt% promoter content, Fe could, and Mn could not be detected by ion scattering spectroscopy on the surface of the catalysts. The Fepromoted catalysts contained Fe2O3-like surface species (EPR, XANES), which could at least in part be removed by washing with oxalic acid. Catalysts were tested for isomerization at 338 K using 1 kPa n-butane in balance of N2. At 0.5 wt% promoter content the maximum rates produced by the 0.5 wt% Mn-promoted and Fe-promoted sulfated zirconia were about 80 and 20 µmol g -1 h -1 , respectively. Mn was thus more effective as a promoter for n-butane isomerization than Fe, despite the more extensive incorporation into the zirconia lattice.

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Section: X-ray Diffractionsupporting

confidence: 64%

Incorporation of manganese and iron into the zirconia lattice in promoted sulfated zirconia catalysts

Jentoft

Hahn

Kröhnert

et al. 2004

Journal of Catalysis

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“…Sulfate groups act as bridging bonds between zirconium atoms and, therefore, at calcination tend to shorten forming bonds in zirconia. Shorter bonds in zirconia provide a tetragonal structure rather than monoclinic [23].…”

Section: Effect Of Sulfate and Ctab Templatementioning

confidence: 99%

Synthesis and characterization of sulfated zirconia mesopore and its application on lauric acid esterification

Rachmat

Trisunaryanti

Sutarno

et al. 2017

Mater Renew Sustain Energy

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Sulfated zirconia mesopore has been successfully prepared from zirconyl oxychloride using structure directing agent cetyl trimethyl ammonium bromide (CTAB) and (NH 4 ) 2 SO 4 . The preparation involved calcination at four different temperatures denoted as MZS (400, 500, 600, and 700°C) and three different zirconyl-to-CTAB ratios (1:1, 3:1, and 9:1). Characterization of resulting zirconia was carried out using XRD method, TEM, gas sorption analyzer, and FTIR. The acidity of zirconia evaluated by ammonia adsorption. Calcination temperatures conducted at 500, 600, and 700°C lead to crystalline structure and tetragonal phase. MZS-600 prepared at ratio 3:1 showed optimum specific surface area, pore diameter, and pore volume: 147.5 m 2 /g, 6.6 nm, and 0.396 cc/g, respectively. CTAB assisted larger pore size formation in zirconia along with higher surface area. The catalytic activity of sulfated zirconia mesopore was tested on lauric acid esterification. All sulfated zirconia mesopores prepared were able to give 99-100% conversion. The highest yield of methyl lauric 89.8% was achieved by MZS-600 prepared using CTAB to zirconyl ratio 9:1.

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“…excellent thermal and chemical stability, high strength and fracture toughness, low thermal conductivity, high corrosion resistance. Both acidic and basic properties of zirconia have been widely used in the fields of structural materials, thermal barrier coatings, oxygen sensors, fuel cells, catalysts and catalytic supports, a possible high dielectric constant material for large scale integrated circuits, and as a gate dielectric in metal oxide-semiconductor (MOS) devices [4][5][6] .Ultrafine zirconia particles have been synthesized via various methods such as sol-gel processing [7][8][9] , chemical vapor synthesis 10 , precipitation from inorganic salt solutions 11,12 , microwave plasma synthesis 13 , inert gas condensation 14 , combustion synthesis 15 , ultrasonically assisted hydrothermal synthesis 16 and laser ablation 17 . In this study we report the synthesis of zirconia nanoparticles synthesized by sol-gel technique in non aqueous medium.…”

Section: Introductionmentioning

confidence: 99%

Effects of precursor on the morphology and size of ZrO2 nanoparticles, synthesized by sol-gel method in non-aqueous medium

et al. 2012

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Pure zirconium oxide (ZrO 2 ) nanoparticles with diameters 10-25 nm were synthesized from ZrOCl 2 .8H 2 O and Zr(SO 4 ) 2 .H 2 O with benzyl alcohol as non-aqueous solvent medium using sol-gel method. Sodium lauryl sulfate was added as surfactants to control the particle size. The synthesized ZrO 2 nanoparticles have a mixture of tetragonal and monoclinic structure. The XRD showed the purity of obtained ZrO 2 nanoparticles with tetragonal and monoclinic phase and the crystallite size for ZrOCl 2 .8H 2 O precursor was estimated to be 18.1 nm and that from Zr(SO 4 ) 2 .H 2 O was 9.7 nm. The transmission electron microscopy and scanning electron microscopic studies also shows different sizes of nanoparticles and different morphology depending on the precursor used for the synthesis of ZrO 2 nanoparticles.

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Comparative study of nanocrystalline zirconia prepared by precipitation and sol–gel methods

Cited by 130 publications

References 21 publications

Incorporation of manganese and iron into the zirconia lattice in promoted sulfated zirconia catalysts

Incorporation of manganese and iron into the zirconia lattice in promoted sulfated zirconia catalysts

Synthesis and characterization of sulfated zirconia mesopore and its application on lauric acid esterification

Effects of precursor on the morphology and size of ZrO2 nanoparticles, synthesized by sol-gel method in non-aqueous medium

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