Heterogeneous burr-like CoNiO2/Ti3C2Tx MXene nanospheres for ultralow microwave absorption and satellite skin application

Nowadays, it is still a challenging task to exploit electromagnetic wave absorption (EMA) materials with superior EMA performance under an ultrasmall thickness (approximately 1 mm). In this study, heterogeneous CoNiO2/Ti3C2Tx MXene hybrid absorbers were successfully synthesized by using a simple and convenient self-assembly process. Benefiting from the increased porosity, heterogeneous interfaces, and multiple polarization processes, the unique burr-like CoNiO2/Ti3C2Tx MXene nanospheres (CNO/MXene-S) exhibited a remarkable EMA capacity with a minimum reflection loss (RLmin) value of −60.61 dB at an ultrasmall thickness of 1.069 mm and −66.79 dB at a matching thickness of 2.565 mm, respectively. The density functional theory (DFT) calculations were utilized to analyze the EMA mechanisms. Furthermore, the satellite radar cross-section (RCS) simulations demonstrated that compared with a non-stealth satellite, a stealth satellite with the CNO/MXene-S absorber exhibited decreased surface reflection of radar waves and a shortened radar detection distance. Therefore, the as-prepared CNO/MXene-S absorber with an ultrasmall matching thickness can be highly promising for the electromagnetic protection of spacecraft and electromagnetic communication devices.