Local Charge Regulation in Selenides via High‐Entropy Engineering to Boost Electromagnetic Wave Absorption

Abstract

Local charge modulation is an effective method to improve the polarization loss and electromagnetic (EM) absorption characteristics. However, the use of conventional means (doping, defects, heterojunction surfaces) remains singular and limited in achieving local charge modulation. Surprisingly, lattice distortions induced by high‐entropy engineering can intrinsically regulate local charge states and improve EM wave absorption performances. Herein, a series of selenides with enhanced configuration entropy are designed and prepared to improve polarization loss capacity. Due to the different radii of the mixed ions and the Jahn‐Teller distortion effect, the local charge of the selenides is effectively modulated by the presence of defects and strong lattice distortions inside the lattice. Uneven distribution of charge at defects and formation of boundaries promotes defect‐induced polarization and interface polarization, respectively. Compared to single NiSe2, high‐entropy (NiFeCuCoMn)Se2 with an entropy value of 1.53R has more severe lattice defects and suitable impedance matching properties, exhibiting good EM absorption properties both in the absorption intensity and respond frequency. Tailoring the local charge density via an entropy strategy paves a new way for the high‐performance EM absorption materials.