Abstract: The colloidal crystal template was prepared by the centrifugal settling of microspheres, whose particle diameters were about 280 nm, from the mother liquor of polymethyl methacrylate(PMMA) obtained by emulsion polymerization. The ethanol-water solution of precursor was formulated with LiNO₃, Mn(Ac)₂·4H₂O, and citric acid in the molar ratio of 1∶2∶2 and was filled into the interstices of PMMA colloidal crystal template. The lithium manganese oxide of three-dimensional ordered macropore(3DOM) was prepared with their composite being dried and roasted in air to form holes. The experiments indicate that the formation of objective product is facilitated when n(Li)/n(Mn)=0.6, the concentration of the precursor was in the range of 0.6—1.0 mol/L, and the roasting temperatures in the two isothermal sections were 300 ℃ and 600 ℃ for 2—3 h separately, and the heating rate was 2 ℃/min. SEM images show that the PMMA colloidal crystal template as well as the 3DOM lithium manganese oxide was arrayed periodically in face-centered cubic closed packing. The macropore diameters were between 200—240 nm, and the pore wall thicknesses between 30—45 nm. Through XRD determination of the crystal phase and the titration analyses of EDTA and KMnO₄, the final product was proved conclusively to be normal spinel LiMn₂O₄.

Key words: Colloidal crystal template method, Poly(methyl methacrylate) microspheres, Three-dimensionally ordered macropores, Spinel type, LiMn₂O₄