Excellent Low‐Frequency Microwave Absorption and High Thermal Conductivity in Polydimethylsiloxane Composites Endowed by Hydrangea‐Like CoNi@BN Heterostructure Fillers

Abstract The advancement of thin, lightweight, and high‐power electronic devices has increasingly exacerbated issues related to electromagnetic interference and heat accumulation. To address these challenges, a spray‐drying‐sintering process is employed to assemble chain‐like CoNi and flake boron nitride (BN) into hydrangea‐like CoNi@BN heterostructure fillers. These fillers are then composited with polydimethylsiloxane (PDMS) to develop CoNi@BN/PDMS composites, which integrate low‐frequency microwave absorption and thermal conductivity. When the volume fraction of CoNi@BN is 44 vol% and the mass ratio of CoNi to BN is 3:1, the CoNi@BN/PDMS composites exhibit optimal performance in both low‐frequency microwave…

• NN
  National Natural Science Foundation of China

  Awards: 52473083, U21A2093, 52403114
• NS
  Natural Science Foundation of Chongqing

  Award: 2023NSCQ‐MSX2547
• FR
  Fundamental Research Funds for the Central Universities

  Awards: D5000240062, D5000240077, D5000240067
• SP
  Shanxi Provincial Key Research and Development Project

  Award: 2023‐YBGY‐461
• NS
  Natural Science Basic Research Program of Shaanxi Province

  Award: 2024JC‐TBZC‐04