High-Yield Production of Few-Layer Graphene via New-fashioned Strategy Combining Resonance Ball Milling and Hydrothermal Exfoliation.

Ming Zhou,Xuyin Li,Yibo Zhang,Wenjun Cheng,Mingyang Yang,Qingfeng Yang,Jianwen Yu,Zhixun Zhang

doi:10.3390/nano10040667

Abstract

Graphene shows great potential applications in functional coating, electrodes, and ultrasensitive sensors, but high-yield and scalable preparation of few-layer graphene (FLG) by mechanical exfoliation method is still a formidable challenge. In this work, a novel two-step method for high-yield preparation of FLG is developed by combining resonance ball milling and hydrothermal treatment. During the resonance ball milling process, the utilization of magnetic Fe3O4 nanoparticles as a new “particle wedge” is beneficial to facilitate fragment and delamination of graphitic layers. In addition, further hydrothermal treatment can enhance ball milling product (BMP) exfoliation because of the shear force driven by the Brownian motion of various molecules at high temperature and high pressure. As expected, the two-step method can have high exfoliation efficiency up to 92% (≤10 layers). Moreover, the FLG nanosheet ink can easily achieve the formation of FLG coatings on the surface of various substrates, resulting in good electrical conductivity, which possesses potential applications in various fields including functional coating, energy storages, and electrochemical sensors, etc. Our work provides a new-fashioned strategy for mechanical large-scale production of graphene.

Highlights

Graphene, a kind of two-dimensional nanomaterial with a single atomic monolayer of sp2-bonded hexagonal carbon, is a rapidly rising star of nanomaterial science since being discovered by Novoselov K
Various methods have been used to prepare graphene, which can be approximately classified into bottom-up synthesis methods including chemical vapor deposition (CVD) [3,4], solution method [5,6], and molecular beam epitaxy (MBE) [7,8], and top-down methods such as mechanical exfoliation [1,13,14,15,16], electrochemical method [17,18], oxidation-reduction method [19,20], and intercalation exfoliation method [21,22], etc
To prepare few-layer graphene, 20 g of expanded graphite and 2.5 g Fe3O4 nanoparticle were milled for 6 h in a ring spring resonance ball mill

Summary

Introduction

A kind of two-dimensional nanomaterial with a single atomic monolayer of sp2-bonded hexagonal carbon, is a rapidly rising star of nanomaterial science since being discovered by Novoselov K. Graphene has attracted considerable attention because of its fabulous mechanical, thermal, and electrical properties, and its promising application [2] During these years, various methods have been used to prepare graphene, which can be approximately classified into bottom-up synthesis methods including chemical vapor deposition (CVD) [3,4], solution (solvent) method [5,6], and molecular beam epitaxy (MBE) [7,8], and top-down methods such as mechanical exfoliation (including the micromechanical cleavage method [1], ultrasonic method [9,10,11], and ball milling method [12], etc.) [1,13,14,15,16], electrochemical method [17,18], oxidation-reduction method [19,20], and intercalation exfoliation method [21,22], etc. Fthuartthhearvme ogroeo,dtheelefcetwric-laalyceorngdruacptihveitnyeo(nFLvGar)ionuasnossuhbestertatiensk, cwahnicehasciolyulfdorhmavfielmpostethntaitalhave good aeplepcltirciactaiolncsoninduvcatriivouitsy foienldvsarinioculusdsiungbsfturnatcetiso,nwalhiccohatcinogu,ldenheargvye pstootreangteisa,l aanpdpleilceacttiroonchseimn ivcaalrious fieldssienncslourds,inetgc.functional coating, energy storages, and electrochemical sensors, etc

Chemicals and Materials

Instruments

Synthesis of Few-Layer Graphene

Preparation of Graphene Conductive Coatings

Results and Discussion

Mechanism of Preparation of the FLG Nanosheets