Magnetically engineering enhanced EMA property through high entropy transition metal ions within all-inorganic perovskite

Abstract

Addressing challenges such as signal interference and crosstalk requires the development of new materials capable of electromagnetic absorption (EMA). In this study, we explored magnetically high-entropy engineering by incorporating transition metal ions into the B sites of all-inorganic CsPbBr3 perovskite. This approach yielded excellent EMA properties, including a minimum reflection loss of 75 dB at 10.2 GHz with a thickness of 2.5 mm and an effective bandwidth of 8.8 GHz. Fe, Co, Ni, and Mn ions were successfully introduced into the CsPbBr3 lattice using high-energy ball milling and the combustion method. Through rigorous characterization techniques such as Rietveld refinement of X-ray diffraction and Grazing-Incidence Wide-Angle Scattering patterns, we confirmed the presence of high-entropy phases. Additionally, we conducted comprehensive studies using Vibrating-sample magnetometer, L2,3 edge XANES, and Mossbauer spectra to investigate the magnetic polarization, spin states, and dipolar exchanges of the transition metal ions. The observed synergistic effects among the magnetic permeability, polarization, and magnetic loss of these ions underscored their role in enhancing the EMA performance of CsPbBr3.