Cellulose-based magnetoelectric composites

Yan Zong,Pedro Martins,Tian Zheng,Zhilian Yue,Michael J Higgins,S Lanceros-Mendez

doi:10.1038/s41467-017-00034-4

Abstract

Since the first magnetoelectric polymer composites were fabricated more than a decade ago, there has been a reluctance to use piezoelectric polymers other than poly(vinylidene fluoride) and its copolymers due to their well-defined piezoelectric mechanism and high piezoelectric coefficients that lead to superior magnetoelectric coefficients of >1 V cm−1 Oe−1. This is the current situation despite the potential for other piezoelectric polymers, such as natural biopolymers, to bring unique, added-value properties and functions to magnetoelectric composite devices. Here we demonstrate a cellulose-based magnetoelectric laminate composite that produces considerable magnetoelectric coefficients of ≈1.5 V cm−1 Oe−1, comprising a Fano resonance that is ubiquitous in the field of physics, such as photonics, though never experimentally observed in magnetoelectric composites. The work successfully demonstrates the concept of exploring new advances in using biopolymers in magnetoelectric composites, particularly cellulose, which is increasingly employed as a renewable, low-cost, easily processable and degradable material.

Highlights

Since the first magnetoelectric polymer composites were fabricated more than a decade ago, there has been a reluctance to use piezoelectric polymers other than poly(vinylidene fluoride) and its copolymers due to their well-defined piezoelectric mechanism and high piezoelectric coefficients that lead to superior magnetoelectric coefficients of >1 V cm−1 Oe−1
ME laminates are assembled by combining a cellulose film, consisting of gold layers sputtered on both sides as inter-face electrodes, with a Metglas film by gluing the two components together using Devcon epoxy to enable strain coupling (Fig. 1c)
Where E and H represent the strength of the electrical and magnetic fields, respectively. αME is calculated as the ME output voltage (V) per unit of cellulose film thickness and Hac strength (Oe)

Summary

Introduction

Since the first magnetoelectric polymer composites were fabricated more than a decade ago, there has been a reluctance to use piezoelectric polymers other than poly(vinylidene fluoride) and its copolymers due to their well-defined piezoelectric mechanism and high piezoelectric coefficients that lead to superior magnetoelectric coefficients of >1 V cm−1 Oe−1 This is the current situation despite the potential for other piezoelectric polymers, such as natural biopolymers, to bring unique, added-value properties and functions to magnetoelectric composite devices. PVDF and its copolymers have been exclusively studied since the first ME polymer composite consisting of PVDF was demonstrated in 2002 and expected developments in exploring other types of piezoelectric polymers have not been forthcoming This has led to the emergence of a central dogma where PVDF is viewed as the “material of merit”, despite the enormous potential for other polymers to bring significant added-value properties and function to ME composite devices. The final laminate composite is tested using a dynamic method, involving the application of an alternating (Hac) magnetic field superimposed on a constant (Hdc) magnetic field, to quantify the ME frequency response and output voltage (Fig. 1d)

Methods

Results

Conclusion