Investigation of the pore-size dependent microwave absorption properties of honeycomb SnO 2

In this work, the honeycomb-like SnO2 with excellent microwave absorbing (MA) capability was successfully prepared by a template method. Furthermore, honeycomb-like SnO2 configuration with various pore sizes can be prepared by altering the size of polystyrene (PS) nano-sphere. The microstructure, crystallographic structure, elemental chemical state and MA properties of honeycomb-like SnO2 were measured by Scanning electron microscopy (SEM), X-ray diffraction (XRD), Thermogravimetric-difffferential scanning calorimetry (TG-DSC) and Vector network analyzer (VNA), respectively. Interestingly, the microwave absorption properties were determined by their honeycomb configurations. Furthermore, honeycomb SnO2 prepared using 148 nm PS spheres as template, presented a minimal RL of −47.4 dB at 11.1 GHz with the layer thickness of 3.2 mm. Meanwhile, the value of RL less than -10 dB was found in the range of 9.8–15.2 GHz. The combination of interfacial polarization, dielectric loss and cellular structure can inhibit the propagation of electromagnetic waves and dissipate microwave energy through heat or other forms. It is believed that the honeycomb-like structures could be expected to be candidates for a new generation of absorbing materials.