College of Physics;
Guizhou Province Key Laboratory for Photoelectrics Technology and Application;
Guizhou University;
Guiyang 550025;
China;
National Laboratory of Solid State Microstructures and Jiangsu Provincial Laboratory for NanoTechnology;
Nanjing University;
Nanjing 210093;
China;
yolk-shell structure; CoNi@void@C; CoNi@void@C@MoS_(2); interface polarization; strong wideband microwave absorbers;