Enhanced Microwave Absorption Properties by Tuning Cation Deficiency of Perovskite Oxides of Two-Dimensional LaFeO₃/C Composite in X-Band

Development of microwave absorption materials with tunable thickness and bandwidth is particularly urgent for practical applications but remains a great challenge. Here, two-dimensional nanocomposites consisting of perovskite oxides (LaFeO₃) and amorphous carbon were successfully obtained through a one pot with heating treatment using sodium chloride as a hard template. The tunable absorption properties were realized by introducing A-site cation deficiency in LaFeO₃ perovskite. Among the A-site cation-deficient perovskites, La_0.62FeO₃/C (L_0.62FOC) has the best microwave absorption properties in which the maximum absorption is -26.6 dB at 9.8 GHz with a thickness of 2.94 mm and the bandwidth range almost covers all X-band. The main reason affecting the microwave absorption performance was derived from the A-site cation deficiency which induced more dipoles polarization loss. This work proposes a promising method to tune the microwave absorption performance via introducing deficiency in a crystal lattice.