Experimental Investigation on Electrical Conductivity, Dielectric Properties, and EMI Shielding Effectiveness of NiP/Graphene-Coated Natural Fiber

Electromagnetic interference (EMI) is a significant source of electromagnetic pollution that disrupts the operation of electronic devices and impacts the functioning of communication and information systems. This has necessitated the development of EMI shielding materials that are recyclable, lightweight, and cost-effective. Moreover, materials with high dielectric properties are in demand for energy storage applications. The present research work aims to develop an electrically conductive woven ramie fiber material through an electroless nickel-phosphorus (NiP)/graphene (Gr) coating to estimate the breaking load resistance, dielectric properties, and EMI shielding effectiveness (SE). From the obtained results, it is inferred that the electrical conductivity of the treated NiP/graphene-coated ramie fiber (T/NiP/Gr/RF) is increased by 74% (14.85 omega cm-1) when compared to the T/NiP/RF fiber (8.54 omega cm-1). An impedance analyzer is used to record the dielectric properties at controlled temperatures between 35 degrees C and 60 degrees C in the 50 Hz to 1 MHz frequency range, and the maximum dielectric constant for the NiP/Gr fiber (72.93 and 35 degrees C) and (29.75 and 60 degrees C). respectively, is observed at 50 Hz. The EMI SE is evaluated using a Keysight 9374A-vector network analyzer test setup at 8-12 GHz (X-band) frequency. The addition of graphene nanoparticles with the treated NiP-coated fiber increases the EMI SET from 47.12 dB to 51 dB. The improved dielectric properties and EMI SET of the T/NiP/Gr/RF material indicate its suitability for use in energy storage and EMI shielding applications.