MoS_(2)/rGO电磁屏蔽材料的可控制备及性能研究

Controllable Preparation of MoS_(2)/rGO Electromagnetic Shielding Materials and Study of Their Properties

随着电磁干扰(EMI)污染的问题日益凸显,亟待研制出具有高度适应性、高效能以及高性能的EMI屏蔽材料。借助水热法与热处理手段能够实现二硫化钼与还原氧化石墨烯(MoS_(2)/rGO)复合材料的制备。rGO片与在其表面原位生成的MoS_(2)纳米片共同构建三维(3D)多孔网络框架,有效防止了二者的堆积。同时,MoS2纳米片与rGO片的结合可以形成稳定的3D导电网络,能够有效提升电子的导电能力和载流子的迁移速率,从而进一步降低体系的传导损耗。此外,该复合材料优异的EMI屏蔽性能可归因于电磁波在材料内部的多次反射和散射。MoS_(2)纳米片与rGO片存在的缺陷位点及其构筑的丰富界面诱导了偶极子极化和界面极化现象,赋予体系优异的EMI屏蔽性能。在X波段范围(8.2~12.4 GHz)内,由于多重损耗机制的协同效应,在厚度为2.0 mm时,MoS_(2)/rGO复合材料的总屏蔽效能(SET)最高可达62.7 dB(平均SET为59.9 dB)。由此可见,MoS_(2)/rGO复合材料具备优异的EMI屏蔽效能,为其他过渡金属硫化物在EMI屏蔽领域的应用研究提供了理论支撑。

As the problem of electromagnetic interference(EMI)pollution is becoming more and more prominent,there is an urgent need to investigate highly adaptable,efficient and high-performance EMI shielding materials.We have successfully prepared molybdenum disulfide and reduced graphene oxide(MoS_(2)/rGO)composites by means of hydrothermal and thermal treatments.rGO sheets and MoS_(2)nanosheets generated in situ on their surface construct a three-dimensional(3D)porous network framework,effectively preventing the accumulation of both materials.At the same time,the combination of MoS_(2)nanosheets and rGO sheets can form a stable 3D conductive network,which can effectively enhance the electronic conductivity and carrier migration rate,thus further reducing the conduction loss of the system.In addition,the excellent EMI shielding performance of the composites can be attributed to the multiple reflections and scattering of electromagnetic waves inside the materials,and the defective sites of MoS_(2)nanosheets and rGO sheets and their rich interfaces induced dipole polarization and interfacial polarization phenomena,endowing the system with excellent EMI shielding performance.In the X-band range(8.2-12.4 GHz),the total shielding effectiveness(SET)of the MoS_(2)/rGO composites reaches up to 62.7 dB(average SET of 59.9 dB)at a thickness of 2.0 mm due to the synergistic effect of multiple loss mechanisms.Thus,the MoS_(2)/rGO composites have excellent EMI shielding performance,which provides theoretical support for the application of other transition metal sulfides in the field of EMI shielding.