Construction of <i>hydrangea</i>-like core–shell SiO ₂@Ti ₃C ₂T _<i>x</i>@CoNi microspheres for tunable electromagnetic wave absorbers

Ti3C2Tx MXene shows great potential in the application as microwave absorbers due to its high attenuation ability. However, excessively permittivity and self-stacking are main obstacles that constrain wide range of applications. To tackle these problems, herein, microspheres SiO2@Ti3C2Tx@CoNi with hydrangea-like core–shell structure were designed prepared by a combinatorial electrostatic assembly hydrothermal reaction method. These constructed an outside layer CoNi nanosheets intermediate wrapping on core modified SiO2, engendering both homogenous heterogeneous interfaces. Such trilayer "magnetic microsize supercapacitors" can not only induce dielectric loss magnetic but also provide multilayer interfaces enhance interfacial polarization. The optimized impedance matching could boost reflection (RL) electromagnetic synergy. synthesized demonstrate outstanding absorption (MA) performance benefited from advantages. obtained RL value was ?63.95 dB at ultra-thin thickness 1.2 mm, corresponding effective bandwidth (EAB) 4.56 GHz. This work demonstrates designing strategy is highly efficient for tuning MA MXene-based microspheres.