Morphology optimization strategy of flower-like CoNiS/CoS@MoS core@shell nanocomposites to achieve extraordinary microwave absorption performances.

Morphology optimization is an effective strategy to take full advantage of interface polarization for the improvement of electromagnetic wave attenuation capability. Herein, a general route was proposed to produce the flower-like core@shell structured MoS-based nanocomposites through a simple hydrothermal process. Through the in-situ hydrothermal reaction between the Mo and S sources on the surface of CoNi nanoparticles, flower-like core@shell structured CoNiS/CoS@MoS nanocomposites could be successfully synthesized. By regulating the hydrothermal temperature, the flower-like geometrical morphology of samples could be effectively optimized, and the as-prepared sample (S2) synthesized at 200 °C displayed very excellent flower-like morphology compared to the samples (S1 and S3) obtained at 180 and 220 °C. Owing to the excellent interface polarization effect, the as-prepared S2 presented the evidently superior comprehensive microwave absorption properties in terms of strong aborption capability, wide absorption bandwidth and thin matching thicknesses compared to those of S1 and S3. The as-prepared core@shell structured CoNiS/CoS@MoS sample with very excellent flower-like morphology simultaneously displayed the minimal reflection loss of -50.61 dB with the matching thickness of 2.98 mm, and the effective absorption bandwidth of 8.40 GHz with the matching thickness of 2.36 mm. Therefore, we provided a general route for the production of flower-like core@shell structured MoS-based nanocomposites, which could make the best of interface polarization to develop high-efficiency microwave absorbers.