The synthesis of CoNi@SiO2@TiO2 core–shell and CoNi@Air@TiO2 yolk–shell microspheres is reported for the first time. Owing to the magnetic–dielectric synergistic effect, the obtained CoNi@SiO2@TiO2 microspheres exhibit outstanding microwave absorption performance with a maximum reflection loss of −58.2 dB and wide bandwidth of 8.1 GHz (8.0–16.1 GHz, < −10 dB).

http://onlinelibrary.wiley.com/doi/10.1002/adma.201503149/full