Enhanced electromagnetic wave absorption, thermal conductivity and flame retardancy of BCN@LDH/EP for advanced electronic packing materials

The limited functionalization of current electronic packaging materials has restricted their use in advanced smart electronic devices with high energy density and low signal delay. In this study, we propose a novel strategy for developing an electronic packaging material (BCN@LDH/EP) that possesses exceptional electromagnetic wave (EMW) absorption, thermal management, and flame-retardant capabilities. BCN@LDH/EP is the double-level hollow core–shell structure (BCN@LDH) composed of a bowl-shaped carbon nanoshell (BCN) and a layered double hydroxide (NiAl-LDH). This structure offers rich heterogeneous interfaces and high specific surface area, thereby generating abundant polarization sites and favorable impedance matching. Consequently, the epoxy resin (EP) shows outstanding EMW absorption performance, with a maximum effective absorption band (EAB) of 6.43 GHz and a minimum reflection loss (RL) value of −55.75 dB at a filling amount of only 10 wt%. Moreover, the closely packed thermally conductive filler BCN@LDH provides a broad pathway for heat transfer within the EP, resulting in a significant thermal conductivity improvement efficiency (η) of ∼170%. Notably, the high-temperature cooling and barrier effects of BCN@LDH also confer excellent flame retardancy to the EP composite, reducing the total heat release (THR) rate by up to 44.9%.