Synthesis of mesoporous Zn–Al spinel oxide nanorods with membrane like morphology

A well-aligned ZnAl2O4 spinel oxide nanorods with hierarchical pore structure was synthesized by a simple route using polycarbonate membrane as the sacrificial template. Spinel formation and the template removal occurred in one-step by calcination at 550 °C. SEM analysis of the calcined sample showed a membrane morphology made up of aligned rods with micron sized pores in between them. TEM analysis revealed that individual rods are 130 ± 30 nm in diameter and are nanoporous in nature. These rods are made up of nanoparticles of the sizes ranging from 5 to 12 nm. HRTEM analysis further showed that these nanoparticles are crystalline with the lattice spacing in commensurate with the ZnAl2O4 spinel oxide. Adsorption–desorption study shows Type IV isotherm with the pore size around 3.4 nm and high specific surface area of about 140 m2/g.