Synthesis and growth behavior of CeO2/ZrO2/LaAlO3 nanorods on hierarchical macroporous gamma-alumina monoliths

Different kinds of metal oxide nanorods (CeO2, ZrO2 and LaAlO3) grown on hierarchical macroporous gamma-alumina monolith with excellent thermostability and mechanical strength are successfully synthesized by combining sol-gel method with boiled water-bath crystallization. Different kinds of metal oxide nanorods have different growth behavior. Monolayer stripe CeO2 nanorods with approximately equal length accumulated by nanoparticles covered mainly on the surface of the skeleton. Minor ZrO2 nanoparticles not only accumulated on the surface but also grew on hollow and conjunct part of the skeleton as well as the internal surface of the pore channels in a stagger and grid way. While the LaAlO3 crystal particles were grown mainly on the skeleton surface of alumina monolith but hardly any on the internal surface. In addition, the dipping time and temperature of metal ions have important effects on the nanoparticles morphology. The unique combination of excellent support and auxiliaries candidates can be used as promising functional materials in the field of heat/mass transfer, microchannel and separation especially in heterogeneous catalysis.