Sol-Gel Synthesis and Spray Granulation of Porous Titania Powder

Abstract

Bimodally porous titania powders with controlled phase composition and porosity made by wet chemical processes have been extensively investigated in our laboratory. This paper reviews experimental parameters affecting the phase and pore structure of these powders. Also, the effect of solution peptization on packing and coordination of particles is discussed. The unpeptized slurry and peptized sol were spray dried to make granules with controlled porosity and morphology. The properties of the product granules were dependent on the feed solution properties. In particular, granules from unpeptized slurry showed bimodal pore size distribution with rough surface attributed to hard aggregates. Granules from the peptized sol showed monomodal pore size distribution with smooth surface of well‐packed microstructures. Potential applications of these granules include adsorbents, catalyst carriers and packing for chromatographic columns.

Zr-doped TiO2nanoparticles synthesized via a sol–gel route and their application in dye-sensitized solar cells for thermo-stabilization

“…3 and Table 2): a) with increasing calcination temperature the average aggregate size increased, b) with increasing average aggregate size, the SSA decreased and c) the addition of Zr increased the SSA. This is in excellent agreement with Kim et al [19] who found that Zr addition had a positive effect on the stabilization of pore structure.…”

“…For sol-gel synthesized nTiO2 powders, Kim et al [19] found a bimodal porosity which consists of large intra-NP pores in the order of ~50-100 nm (due to voids between NPs making up the aggregates) and small pores of 2-5 nm within the NPs (the NPs are composed of crystallites). Zr-doping allowed maintaining pore populations up to relatively high calcination temperatures.…”

Nano Particle Sizing – Vorteile durch NIBS‐Technologie

“…Die Darstellung von nanoskaligem Titan(IV)oxid erfolgt durch Umsetzung von Tetra-isopropyl-orthotitanat in einer salpetersauren wässrigen Lösung [1]. Anschlieûend werden die entstandenen Präzipitate über ein Zeitraum von 24 Stunden peptisiert.…”

Packaging of Sol–Gel‐Made Porous Nanostructured Titania Particles by Spray Drying

“…Some of the unpeptized and peptized samples were dried at 110°C, then calcined at different temperatures, to allow comparison with the spray-dried samples. 17 Alumina-and zirconia-doped titania sols were also synthesized by the cohydrolysis and condensation of TTIP and dopants of aluminum tri-sec-butoxide (ATSB, Al(OC 4 H 9 ) 3 , 97%; Aldrich) or zirconium n-propoxide (ZNP, Zr(OC 3 H 7 ) 4 , 70%; Fluka Chemical Corp., Ronkonkoma, NY). First, the TTIP was dissolved in anhydrous ethyl alcohol, as described above.…”

“…Thus, the peptized titania granules and the powders exhibited a similar tendency in SSA. 17 The small difference in SSA values can be attributed to the different geometries of the two samples. The peptized titania granules had a largely spherical shape, whereas the peptized titania powders were flakelike.…”