Facile synthesis of MAPbI3/CNTs composites with superior electromagnetic wave absorption performances

Perovskite shines as a top contender in the realm of electromagnetic waves (EMW) absorption, owing to its unique physical properties, structural characteristics, and multifunctionality. However, it is still a huge challenge to synthesize high-performance EMW absorbing perovskite materials with environmental-friendly and sustainable processes, despite the simplicity of the perovskite preparation procedures. To address this issue, a facile solvent-free method was developed in this study for CH3NH3PbI3 (MAPbI3), then introduced carbon nanotubes (CNTs) and subsequently prepared MAPbI3/CNTs (MC) composites using a simple procedure. The frequency, thickness, reflection loss (RL), and effective absorption bandwidth (EAB) of MC for EMW absorption were systematically investigated by adjusting the filling amount and component ratio of MC. It is interesting to find that the as-prepared MC composites always achieve high absorption intensities in X and Ku bands. Moreover, an appropriate amount of CNTs can further optimize the impedance matching of MC and promote the loss capability of MAPbI3.With a loading ratio of 25 wt% and a mass ratio of 2:1 between MAPbI3 and CNTs, the MC sample exhibits excellent absorption capability, achieving the lowest RL of -63.8 dB at 1.8 mm and the maximum EAB of 5.16 GHz at 1.69 mm. These findings contribute to the design and development of organic-inorganic halide perovskite absorbers with superior EMW absorption performances.