ABSTRACT

Boron nitride nanosheets (BNNSs) are an exemplary member of the graphene-analogous 2D nanomaterial family (Golberg et  al. 2010, Lin 2012a, Lu et  al. 2012, Pakdel et  al. 2012, Song et al. 2013). However, BNNSs had not captured much interest from scientists until graphene was exfoliated from graphite in 2004 by Novoselov et  al. (2004). Shortly thereafter, BNNSs were exfoliated from hexagonal boron nitride (h-BN) by the same group of researchers (Novoselov et  al. 2005). In both cases, the preparations were achieved via mechanical exfoliation by simply using a piece of adhesive tape, that is, the Scotch tape method. Sharing a nearly identical geometrical structure to graphene, BNNSs also have superb mechanical strength and high thermal conductivity. However, BNNSs have an intrinsically wide bandgap (~4-6 eV) in comparison to conductive graphene. These property differences make BNNSs potentially useful in applications where graphene may not be desirable. For example, BNNSs are attractive for use as thermally conductive but electrically insulating fillers for

14.1 Introduction 367 14.2 eoretical Investigations of BNNS Chemistry 370

14.2.1 Electronic and Magnetic Properties of Pristine BNNSs and BNNRs 370 14.2.2 Defects and Doping 370 14.2.3 Edge Modication of BNNRs 375 14.2.4 Surface Modications 377

14.3 Experimental Investigations of BNNS Chemistry 383 14.3.1 Direct Liquid Dispersion: Solvents and Melts 383 14.3.2 Noncovalent Chemistry: Surfactants and Polymers 385 14.3.3 Ionic Chemistry: Lewis Acid-Base Interactions 389 14.3.4 Covalent Chemistry: Basal Plane Functionalization and Others 389 14.3.5 Decoration with Inorganic Nanoparticles 392 14.3.6 Conjugates with Biomolecules 396 14.3.7 Doping 397

14.4 Summary 400 References 401

polymer or ceramic composites, thermal radiators, deep ultraviolet light emitter and lasers, and nanoelectronic devices. As h-BN is nicknamed white graphite, the monolayer BNNSs are often referred to as white graphene (Zeng et al. 2010, Liu et al. 2011).