The uniform zirconia nanoparticle multilayers/micrometer-sized silica particle(ZrO 2/SiO 2) was prepared for HPLC support material by layer-by-layer(LbL) self-assembly technique. XRD pattern shows that the crystalline of nanometer particles on the surface is pure tetragonal zirconia, with a diameter of 13^9 nm. The specific surface area, pore volume and pore size of the material are 172.53 m 2/g, 0.378 4 cm 3/g, and 8.5 nm, respectively. The novel support not only has the mechanical strength and chemical stability of zirconia, but also has the good chromatographic features such as larger surface area, better permeability, less background pressure.
The surface properties of zirconia-based supports,ZrO-2/SiO-2 and ZrO-2,were compared.ZrO-2/SiO-2 prepared by layer-by-layer self-assembly(LbL SA) technique showed more favorable characteristics for HPLC applications compared with ZrO-2 prepared by modified oil-emulsion method.The specific surface area and pore volume of ZrO-2/SiO-2 were about 18 and 20 times of those of ZrO-2 respectively.The pore of ZrO-2/SiO-2 support was ideal cylindrical shape,but ZrO-2 support had some \!ink bottle\" shaped-pores which was unfavorable for HPLC separations.Pore size distribution of ZrO-2/SiO-2 supports was more uniform than that of ZrO-2 supports.
