Tailoring the Electromagnetic Response of MoS₂ through Ni Doping for Promising Microwave Absorber

Abstract

. Transition-metal doping offers a promising route to enhance the microwave absorption performance of layered materials. In this work, Ni-doped MoS₂ nanostructures with varying concentrations (0–4 at%) were synthesized via a hydrothermal method to systematically investigate the effect of Ni incorporation on structural, magnetic, and electromagnetic properties. XRD analysis confirmed that Ni doping preserved the hexagonal MoS₂ phase while inducing lattice contraction and reduced crystallite size. SEM observations revealed increasingly compact agglomerated nanosheet-flower morphologies with higher Ni content, indicative of enhanced nucleation and crystal growth. VSM measurements demonstrated that Ni doping significantly improved magnetic properties, with the 4 at% sample exhibiting the highest saturation magnetization (1.101 emu/g) and lowest coercivity (830 Oe), characteristic of soft ferromagnetism. Microwave absorption tests in the X-band (8–12 GHz) showed that Ni doping markedly increased reflection loss and broadened the effective bandwidth. Optimal performance was achieved at 4% Ni, with a maximum reflection loss of –27.91 dB (approximately 99.84% absorbance) at 10.60 GHz and an effective bandwidth of 0.64 GHz. These findings highlight Ni doping as an effective strategy to tailor the electromagnetic response of MoS₂, offering strong potential for stealth technology and electromagnetic interference (EMI) shielding applications.