Facile synthesis of urchin-like ZnO hollow spheres with enhanced electromagnetic wave absorption properties

Urchin-like ZnO hollow spheres were synthesized by a simple hydrothermal method and their electromagnetic and microwave absorbing properties were investigated. The enlarged SEM image shows that as-prepared ZnO precursor is composed of randomly close-packed porous nanosheets. On the contrary, well-crystallized ZnO spheres are obtained after calcination. The TEM images provide further insight into the detailed structure, showing the typically...