Phase Engineering of MoS2 via Anderson‐Type Polyoxometalate Precursor for Efficient Electromagnetic Wave Absorption

Abstract Molybdenum disulfide (MoS 2 ) with tunable phase transformation, especially with high 1T‐phase content, has been a promising electromagnetic wave (EMW) absorber. However, precise regulation of MoS 2 phase transformation still remain challenges. Herein, a facile Anderson‐type polyoxometalate (XMo 6 ,X = Cr, Mn, Fe, Co, Ni) precursor strategy is reported to construct phase transformation tunable MoS 2 ‐based bimetallic sulfide hybridsfor regulating permittivity and EMW absorption. The well‐defined structures and tailorable compositions of XMo 6 offer the opportunity to conduct controllable regulation on phase engineering of MoS 2 . The disparity of MoS 2 and transition metal sulfides (TMSs) in chemical reactivity leads to sulfur vacancy (V s ), which induces phase transformation of MoS 2 from 2H to 1T. The tuning of the electronic structure in MoS 2 enables precise regulation of permittivity, which is further verified by density‐functional theory (DFT) calculations. The optimized FeS/MoS 2 /carbon fiber powder with richer 1T‐phase, V s , heterointerfaces and multi‐component, exhibit a minimum reflection loss of −51.82 dB (1.72 mm) and an effective absorption bandwidth of 6.1 GHz (1.64 mm). This work establishes the logical relationship between the intrinsic structure of MoS 2 and EMW absorption, offering an effective method for regulating permittivity.