Utilizing distinctive crystalline/amorphous nano-domains to facilitate multi-polarization behavior for broadband electromagnetic wave absorption

The polarization effect has been unequivocally demonstrated to markedly enhance the microwave absorption performance. However, the pursuit of achieving broadband absorption through meticulously designed polarization behavior continues to pose a formidable challenge. In this work, we present a unique multi-polarization strategy in the La(OH)₃/N-doped rGO composites, incorporating dipole polarization induced by nitrogen doping and intrinsic defects, homogeneous interfacial polarization contributed by locally crystalized nano-domains in La(OH)₃, and heterogeneous interfacial polarization at the heterojunctions between La(OH)₃ and N-doped rGO, to significantly enhance the multi-band polarization loss. Experimental and theoretical investigations reveal that the La(OH)₃/N-doped rGO hybrid featuring distinctive crystalline/amorphous nano-domains exhibits remarkable coupling effects, encompassing an enhanced electron transport rate and strengthened interfacial electron interactions. The improved electron transport is attributed to increased electron transitions at heterojunctions with matched Fermi levels and enhanced charge conduction from the crystalline regions within La(OH)₃. Furthermore, strong polarization relaxation at these heterojunction interfaces, along with weaker but significant polarization at numerous homogeneous interfaces, contributes to the enhanced interactions. Consequently, an exceptional minimal reflection loss of -69.6 dB has been achieved, accompanied by an impressive effective absorption bandwidth of 7.7 GHz, which surpasses that of the current state-of-the-art microwave absorbers. This work unveils an innovative design paradigm aimed at the meticulous regulation of polarization loss, thereby laying a robust foundation for the advancement of high-performance absorbers.