The Role of Two-Dimensional Materials in Electromagnetic Interference Shielding

Introduction

The extensive use of electronic and wireless technologies has led to the need to develop materials that present high performance shielding against electromagnetic interference (EMI), which avoid pollution by electromagnetic waves that affect the operation and life time of electronic devices as well as the Human health (Song, 2017; Wang, 2017; Liu, 2019). Commonly, metallic materials are used in practical ways to increase the shielding effectiveness (SE) through an appropriately designed assembly process. Unfortunately, the high density of devices that require it and the poor environmental stability of metals have impeded their massive use. In addition, materials with light weight and good chemical stability are also required for applications in the automotive, aerospace and electronics industries.

Research in the area of materials engineering has introduced two-dimensional materials in the last decades as an alternative option to increase the efficiency of electromagnetic shielding. Two-dimensional materials are defined as crystalline materials of a single layer of two-dimensionally arranged allotropic atoms based on elements or compounds (two or more covalently bonded elements). In the following paragraphs, the fundamental role that these materials play in the future of electromagnetic shielding is introduced. The advent of two-dimensional materials in the area of electromagnetic interference will mitigate the harmful effects of excessive use of electronic and telecommunications devices through electromagnetic shielding for commercially, industrially and militarily used systems. In this way, the manufacture of electronic systems must include an electronic packaging that involves the application of two-dimensional materials used as electronic fillers in composite materials based on polymeric, ceramic or metallic matrices. From a commercial point of view, the integration of two-dimensional materials will provide a high added value to products that include more efficient electromagnetic shielding than that achieved with current technologies.

Carbon-based nanomaterials such as graphene and carbon nanotubes have recently been introduced to control electromagnetic interference or mitigate contamination by electromagnetic radiation, and because they offer characteristics such as low density, high electrical conductivity and good chemical resistance (Dhakate, 2015; Xu, 2018; Zhao, 2018a). Of these nanomaterials, graphene is a two-dimensional carbon material with a higher electrical conductivity than carbon nanotubes, which further increases the shielding effectiveness (Bhattacharjee, 2017; Liu, 2019). To use the multifunctional properties of these nanomaterials in practical applications, it is necessary to implement nanocomposites that contain them regularly embedded in polymer matrices. Two-dimensional materials must be incorporated in small quantities and form efficient conductive networks within the composite material that will be formed by exploiting their high intrinsic electrical conductivity, large aspect ratio, good dispersion, and homogeneous distribution.