Creation of localized spins in graphene by ring-opening of epoxy derived hydroxyl.

Jie Chen,Youwei Du,Yuanyuan Sun,Nujiang Tang,Yongping Zheng,Weili Zhang

doi:10.1038/srep26862

Abstract

Creation of high-density localized spins in the basal plane of graphene sheet by introduction of sp3-type defects is considered to be a potential route for the realization of high-magnetization graphene. Theoretical and experimental studies confirmed that hydroxyl can be an effective sp3-type candidate for inducing robust magnetic moment. However, the artificial generation of hydroxyl groups for creating high-density spins on the basal plane of graphene sheet is very scarce. Here we demonstrate that high-content hydroxyl groups can be generated on the basal plane of graphene oxide (GO) sheet by ring opening of epoxy groups. We show that by introduction of 10.74 at.% hydroxyl groups, the density of localized spins of GO can be significantly increased from 0.4 to 5.17 μB/1000 C. Thus, this study provided an effective method to obtain graphene with high-density localized spins.

Highlights

Samples Epoxy groups Hydroxyl groups Ms Spin density J (OHG) with high-content hydroxyl groups was obtained by treating GO using NaBH4
It is known that there is difference in the content and distribution of hydroxyl and epoxy groups in GO reported because of the various synthesis conditions[22,23,25,32,33,34], and this is considered to be the reason that the reported magnetism of GO via chemical exfoliation of graphite is multifarious[22,23]
We can see that compared with OHG, OHG-90 has the higher content of hydroxyl groups but the lower magnetization

Summary

Introduction

Samples Epoxy groups (at.%) Hydroxyl groups (at.%) Ms (emu/g) Spin density (μB/1000 C) J (OHG) with high-content hydroxyl groups was obtained by treating GO using NaBH4. Our results clearly indicate that by generating high-content hydroxyl groups via ring opening of epoxy groups, the high-density localized spins can be created on the basal plane of OHG sheets. We show that the magnetization of GO can be increased from 0.136 to 3.11 emu/g via ring opening of epoxy groups combined Ar annealing method

Methods

Results

Conclusion