Thursday, December 31, 2009

Synthesis, characterization, and evaluation of lubrication properties of composites of ordered mesoporous carbons and luminescent CePO4:Tb nanocrystals

Synthesis, characterization, and evaluation of lubrication properties of composites of ordered mesoporous carbons and luminescent CePO4:Tb nanocrystals: "

Abstract  Having new potential applications in forging processes in mind, composites of an ordered mesoporous carbon and luminescent
metal phosphate nanocrystals were synthesized for the first time. Three kinds of CMK-3/CePO4:Tb nanocomposites were prepared by treating a mesoporous CMK-3 host with different lanthanide phosphate precursor solutions.
Characterization of the obtained nanocomposites by small-angle X-ray scattering, wide-angle X-ray diffraction, transmission
electron microscopy, thermogravimetry, and nitrogen physisorption analysis showed that in two cases, the nanocrystals (ca.
2–3 nm in size) were located inside the mesopores, whereas in the third case the nanocystals (ca. 6 nm in size) merely adhered
to the outer surfaces of the carbon particles. The CMK-3 and the two nanocomposites had ordered hexagonal structures (space
group p6mm); all the materials possessed amorphous carbon walls. After combustion of the nanocomposites, the residues upon excitation
with UV light exhibited the typical green luminescence of Tb3+. A preliminary evaluation of the lubrication properties of the CMK-3 and one nanocomposite material was performed. The friction
factors determined by means of ring upsetting tests revealed that the carbon materials were able to lower frictional forces
although they were 3–4 times less efficient than a commercial graphite-based reference lubricant.


  • Content Type Journal Article
  • DOI 10.1007/s10853-009-4130-3
  • Authors

    • Falk Heinroth, Leibniz Universität Hannover Institut für Anorganische Chemie Callinstr. 9 30167 Hannover Germany
    • Dominic Gruss, Institut für Integrierte Produktion gGmbH Holleritallee 6 30419 Hannover Germany
    • Sven Müller, Institut für Integrierte Produktion gGmbH Holleritallee 6 30419 Hannover Germany
    • Florian Waltz, Leibniz Universität Hannover Institut für Anorganische Chemie Callinstr. 9 30167 Hannover Germany
    • Julia Martynczuk, Leibniz Universität Hannover Institut für Physikalische Chemie und Elektrochemie Callinstr. 3A 30167 Hannover Germany
    • Armin Feldhoff, Leibniz Universität Hannover Institut für Physikalische Chemie und Elektrochemie Callinstr. 3A 30167 Hannover Germany
    • Peter Behrens, Leibniz Universität Hannover Institut für Anorganische Chemie Callinstr. 9 30167 Hannover Germany
    • Michael Wiebcke, Leibniz Universität Hannover Institut für Anorganische Chemie Callinstr. 9 30167 Hannover Germany


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