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Calcium phosphate nanoparticles with calcium/phosphorus molar ratios ranging from 1.43 to 1.67 have been synthesized by simultaneous combustion of calcium carboxylate and tributyl-phosphate based precursors in a flame spray reactor. Fluoro-apatite and zinc or magnesium doped calcium phosphates were obtained by adding trifluoroacetic acid or corresponding carboxylates into the fuel. Nanoparticle morphology and the structure of sintered ceramics were studied using transmission and scanning electron microscopy. Thermal evolution of calcium phosphate phases was investigated by powder X-ray diffraction, Fourier transform infrared spectroscopy, and thermal analysis. A molar ratio of Ca/P < 1.5 in the precursor promoted the formation of dicalcium pyrophosphate (Ca2P2O7). Phase pure β-tricalcium phosphate was obtained with a precursor Ca/P ratio of 1.52 after subsequent calcination at 900 °C. The regular, open structure with interconnecting micropores and the facile substitution of both anions and cations suggests possible application as a biomaterial.

Spraying cerium and zirconium precursors dissolved in carboxylic acids into a methane-oxygen flame resulted in well-structured nanocrystals of ceria-zirconia mixed oxides with high temperature stability and surface area.

A series of mixed-linker metal-organic frameworks (MIXMOFs) of the general formula Zn 4 O(BDC) x (ABDC) 3-x has been synthesized and tested as catalyst in the reaction of propylene oxide (PO) and carbon dioxide. Based on MOF-5 a new synthetic route was developed which allows the partial substitution of benzene-1,4-dicarboxylate (BDC) linkers in the material by functionalized 2-aminobenzene-1,4-dicarboxylate. In that way the number of catalytically active amino groups can be tuned using the desired BDC/ABDC ratio. The presence of MIXMOFs (instead of a mechanical mixture of MOF-5 and IRMOF-3) was proven by high-resolution X-ray diffraction and DTG. XRD and TG/MS analysis revealed that pure MIXMOF materials can be obtained up to an ABDC loading of 40 %. The thermal stability in air is decreasing with increasing ABDC content from 450°C for pure MOF-5 (0 % ABDC) to ca. 350°C for the 40 % MIXMOF Zn 4 O(BDC) 1.8 (ABDC) 1.2 . Consequently, MIXMOF materials represent a promising class of materials for catalytic applications in the temperature range at least up to 300°C which is