Simultaneous modulation of vacancy and heterointerface of double-matrix phosphorus doped NiSe₂/CoSe₂ composite for “dual-core-driven” electromagnetic wave absorption

In order to achieve an efficient response of the absorber to electromagnetic waves (EMW), vacancy modulation and phase optimization of the composites are crucial. In this study, a phosphorus-doped vacancy modulation and phase interface optimization engineering was designed to prepare nine metal organic frameworks (MOFs)-derived metal selenides@carbon double matrix P-doped NiSe₂/CoSe₂@NC (PNCS). The optimal solution of the EMW absorber mechanism was explored by modulating the doping concentration and the calcination temperature. The selection of safeguarded priorities in this work is of constructive significance for the rationalization of EMW absorber preparation is constructive. Upon achieving a ratio of one third of the phosphorus source in the selenide matrix, the calcination temperature of 400 °C introduces moderate defects, thus providing the sample with optimal EMW absorption capabilities. With a maximum effective absorption bandwidth of 7.04 GHz at an ultra-thin matching thickness of 2.1 mm. This value covers the entire X and Ku bands within a usable thickness of 2.6 mm, which is significantly superior to other samples of the same type samples. The “dual-core-driven” strategy of heterogeneous interfaces and oxygen vacancies optimizes dielectric relaxation and polarization, supporting a prospective effect on the development and wide application of novel EMW absorbers.