Atomic-Scale Layer-by-Layer Deposition of FeSiAl@ZnO@Al2O3 Hybrid with Threshold Anti-Corrosion and Ultra-High Microwave Absorption Properties in Low-Frequency Bands
Wei Tian, Jinyao Li, Yifan Liu, Rashad Ali, Yang Guo, Longjiang Deng, Nasir Mahmood, Xian Jian
Abstract
Abstract Developing highly efficient magnetic microwave absorbers (MAs) is crucial, and yet challenging for anti-corrosion properties in extremely humid and salt-induced foggy environments. Herein, a dual-oxide shell of ZnO/Al 2 O 3 as a robust barrier to FeSiAl core is introduced to mitigate corrosion resistance. The FeSiAl@ZnO@Al 2 O 3 layer by layer hybrid structure is realized with atomic-scale precision through the atomic layer deposition technique. Owing to the unique hybrid structure, the FeSiAl@ZnO@Al 2 O 3 exhibits record-high microwave absorbing performance in low-frequency bands covering L and S bands with a minimum reflection loss (RL min ) of -50.6 dB at 3.4 GHz. Compared with pure FeSiAl (RL min of -13.5 dB, a bandwidth of 0.5 GHz), the RL min value and effective bandwidth of this designed novel absorber increased up to ~ 3.7 and ~ 3 times, respectively. Furthermore, the inert ceramic dual-shells have improved 9.0 times the anti-corrosion property of FeSiAl core by multistage barriers towards corrosive medium and obstruction of the electric circuit. This is attributed to the large charge transfer resistance, increased impedance modulus |Z| 0.01 Hz , and frequency time constant of FeSiAl@ZnO@Al 2 O 3 . The research demonstrates a promising platform toward the design of next-generation MAs with improved anti-corrosion properties.