# Study on the Absorbing Properties of V-Doped MoS2
## 1 Introduction  
Wireless communication technology has been extensively applied across various domains, including the Internet of Things, mobile communication, intelligent transportation, medical health, satellite communication, and quantum technology. Concurrently, EM pollution has emerged as a novel form of environmental contamination. Its adverse effects encompass interference with communication signals, potential hazards to human health, and disruption of military applications. The rapid advancement of 5G communication, coupled with the widespread adoption of portable smart devices such as mobile phones, computers, and wearable devices like bracelets, has significantly enhanced the convenience of modern life. However, the resultant EM radiation poses substantial risks. It not only presents harm to physical health but also interferes with the operation of precision instruments [1, 2, 3]. To address the growing issue of EM pollution, the development of high-performance EM microwave absorbing materials (MAMs) has emerged as a key research focus [4, 5]. Molybdenum disulfide (MoS2), a metal sulfide, is a popular candidate for the study of MAMs due to its 2D layered structure and excellent electrical properties [6, 7, 8]. However, the absorption performance of pure MoS2 remains constrained in terms of broadband absorption and high absorption efficiency, primarily due to its poor impedance matching and insufficient dielectric loss. In recent years, researchers have significantly enhanced the EM wave absorption performance of MoS2 through morphology control and composite strategies [9, 10]. For example, [PERSON] et al. fabricated two-dimensionalMoS\({}_{2}\)/graphene hybrid nanosheets with isomorphic heterostructures through liquid-phase exfoliation and hydrothermal synthesis. By regulating the ratio of MoS\({}_{2}\)/graphene, optimized sample achieves an EAB of 5.6 GHz at 2.2 mm thickness [11]. [PERSON] and his group developed hollow carbon spheres@MoS\({}_{2}\) composites via template etching-hydrothermal methods. The introduced MoS\({}_{2}\) nanosheets significantly improved interfacial polarization loss ability of hollow carbon spheres@MoS\({}_{2}\) composites, thereby enhancing the overall EM wave absorption performance [12]. However, morphology control and composite strategies often involve complex synthesis procedures and high costs, which hinder the large-scale application of MAMs.  
Doping is an effective strategy for tuning the physicochemical properties of materials. In MAMs, elemental doping can alter charge distribution, modulate electrical conductivity, and introduce additional polarization centers, thereby simultaneously enhancing dielectric loss and improving impedance matching [13,14]. For MoS\({}_{2}\), vanadium (V) is considered an ideal doping element due to its unique 3D orbital configuration and multivalent nature. On the one hand, the ionic radius of V is similar to that of Mo, allowing it to be stably incorporated into the MoS\({}_{2}\) lattice without compromising the structural integrity of the crystal. On the other hand, compared to other transition metal dopants (Fe, Co, Ni), V doping can enhance conduction loss without introducing magnetic responses, which is advantageous for precise regulation of the dielectric loss mechanism and enables single-variable analysis. Therefore, in this work, V-doped MoS\({}_{2}\) was selected as the research focus. This approach aims to investigate the dielectric properties and microwave absorption performance of V-doped MoS\({}_{2}\). The findings offer a new design strategy for developing high-performance two-dimensional MAMs.