10.1016/j.materresbull.2007.06.005
Synthesis and characterization of nanocrystalline La2Mo2O9 fast oxide-ion conductor by an in-situ polymerization method

Nanocrystalline La2Mo2O9 powder was prepared by an in situ polymerization method using polyacrylates of La and Mo as the precursor compound. The polymeric precursor was made by solution polymerization of aqueous solution of acrylic acid in presence of La(NO3)3 and (NH4)6Mo7O24 with (NH4)S2O8 as the initiator. The typical experimental procedure is first to dissolve the stoichiometric amount of La(NO3)3*6H2O and (NH4)6Mo7O24*4H2O in triple distilled water and then the solution is pour into a acrylic acid solution (acrylic acid:H2O, 70:30 wt%) with constant stirring. To this a small amount of 5% (NH4)S2O8 solution was added as initiator to promote the polymerization. Under heating at ~80 degC, a well-distributed polyacrylates of La and Mo is formed. Afterward the resultant polyacrylates were dried at 120 degC for 1-2 h. The dried polymeric precursor was further heated to 520 degC for 5 h in air with a heating rate of 5 degC/min to eliminate the residual organic phase and get a nanocrystalline lanthanum molybdate powder.
acrylic acid solution
acrylic acid:H2O
70:30 wt%
wt%
(NH4)S2O8
added
5%
%
La and Mo
heating
~80 degC
degC
polyacrylates
dried
120 degC
degC
polyacrylates
dried
1-2 h
h
dried polymeric precursor
heated
520 degC
degC
dried polymeric precursor
heated
5 h
h
dried polymeric precursor
heating rate
5 degC/min
degC/min