One-pot synthesis and characterization of novel sodium tris(glycozirconate) and cerium glycolate precursors and their pyrolysis

Abstract

A low-cost and facile route to the synthesis of bimetallic glycolato zirconate (Na 2Zr(C 2H 4O 2) 3) and homometallic glycolato cerate (Ce(C 2H 4O 2)), which can be used as alkoxide precursors for sodium zirconium oxide (and/or zirconia by sol–gel process) and ceria materials, has been developed from the reaction of inexpensive starting materials via the oxide one-pot synthesis (OOPS) process. Both complexes were directly synthesized from zirconium hydroxide/cerium hydroxide and ethylene glycol using base as catalyst. Sodium hydroxide was used in the synthesis of sodium tris(glycozirconate) complex while both triethylenetetramine (TETA) as catalyst and trace amount of sodium hydroxide as co-catalyst were used in the case of cerium glycolate complex. The structures of obtained products were investigated using FTIR, TGA, DSC, 1 H and 13 C NMR, elemental analyses, EDS and mass spectroscopy. Pyrolysis studies delineate the effects of temperature on the decomposition processes whereby sodium tris(glycozirconate) and cerium glycolate precursors transform into Na 2O·ZrO 2 and CeO 2, respectively. The resulting sodium zirconium oxide and ceria, after pyrolysis at 600 °C for 3 h, had BET surface areas of about 62 and 70 m 2 g −1, respectively, and show monomodal pore size distributions in the mesopore region.