Fabrication and Characterization of Waste Wood Cellulose Fiber/Graphene Nanoplatelet Carbon Papers for Application as Electromagnetic Interference Shielding Materials.

Jihyun Park,Lee Ku Kwac,Hye Kyoung Shin,Hong Gun Kim

doi:10.3390/nano11112878

Abstract

Waste wood contains large amounts of cellulose fibers that have outstanding mechanical properties. These fibers can be recycled and converted into highly valuable materials of waste wood. In this study, waste wood cellulose fiber/graphene nanoplatelet (WWCF/GnP) papers were prepared according to the WWCF and GnP contents. Subsequently, the WWCF/GnP papers were varyingly carbonized for their application as electromagnetic interference (EMI) shielding materials such as state-of-the-art electronic equipment malfunction prevention, chip-level microsystem, and micro intersystem noise suppression/reduction. The increase in the GnP content and carbonization temperature enhanced electrical conductivity, thereby generating a greater EMI shielding effectiveness (EMI SE) in the high-frequency X-band. Additionally, the thickness of the WWCF/GnP carbon papers improved the electrical conductivity and EMI SE values. The electrical conductivity of the WWCF/GnP-15 carbon paper obtained at carbonization temperature of 1300 °C was approximately 5.86 S/m, leading to an EMI SE value of 43 decibels (dB) at 10.5 GHz for one sheet. Furthermore, overlapping of the three sheets increased the electrical conductivity to 7.02 S/m, leading to an EMI SE value of 72.5 dB at 10.5 GHz. Thus, we isolated WWCFs, without completely removing contaminants, for recycling and converting them into highly valuable EMI shielding materials.

Highlights

Consumption of fossil fuels and generation of wastes has led to severe environmental problems worldwide
The alkali-cooked waste wood chips were beaten by a pestle to separate them into fibers, and they were bleached using 10 wt % H2 O2 solution and 5 wt % H2 O2 stabilizer for 1 h at 80 ◦ C to obtain cellulose fibers (CF)
The waste wood CFs (WWCFs) and Graphene nanoplatelets (GnPs) papers were homogenously mixed in water according to weight percentage ratios (95:5, 90:10, and 85:15), and 1 wt % polyacrylamide solution was added as a binder

Summary

Introduction

Consumption of fossil fuels and generation of wastes has led to severe environmental problems worldwide. Waste wood contains large amounts of cellulose fibers (CF). These CF of semi-crystalline fibers have outstanding mechanical properties owing to the high aspect ratios of fibers and have been utilized in papers, composites, and coatings [9,10,11]. Highly valuable materials of waste wood can be obtained, irrespective of complete removal of contaminants, by recycling and converting the CF. These materials can be further researched as electromagnetic interference (EMI) shielding materials

Methods

Results

Conclusion