How Do the Electrical Properties of Graphene Change with its Functionalization?

Abstract

Functionalization of graphene is essential to interface it with other moieties to expand the scope of its electrical/electronic applications. However, chemical functionalization and/or molecular interactions on graphene sensitively modulate its electrical properties. To evaluate and take advantage of the properties of functionalized graphene, it is important to understand how its electrical attributes (such as carrier scattering, carrier concentration, charge polarity, quantum-capacitance enhanced doping, energy levels, transport mechanisms, and orbital hybridization of energy-bands) are influenced by a change in carbon's structural conformation, hybridization state, chemical potential, local energy levels, and dopant/interface coupling induced via functionalization or molecular interactions. Here, a detailed and integrated model describes factors influencing these electrical characteristics of functionalized graphene (covalent bonds, adsorption, π-π bonds, and lattice incorporation). The electrical properties are governed via three mechanisms: (a) conversion of carbon's hybridized state, (b) dipole interactions enhanced via quantum capacitance, and (c) orbital hybridization with an interfacing molecule. A few graphenic materials are also identified where further studies are essential to understand the effect of their functionalization.

Graphene based metal and metal oxide nanocomposites: synthesis, properties and their applications

“…110 Nevertheless, significant efforts have been made to prepare homogeneous suspensions of GRO sheets in water as well as in various non-aqueous solvents by chemical functionalization of GO. 68,[111][112][113] Usually, chemical functionalization would decrease the density of the hydrogen bonding donor groups such as the hydroxyl group in GO and thus undermine the strength of the hydrogen bonding, thereby rendering less hydrophilic GRO sheets. 110 The oxygen containing groups (such as carboxyl and hydroxyl groups) that exist in GO facilitates the functionalization by providing reactive sites for chemical modification.…”

Oxide Resistive Memory with Functionalized Graphene as Built‐in Selector Element

“…[ 13 ] To this end, instead of using conventional metal electrodes RRAM devices can be integrated with novel electrode materials such as graphene to take advantage of the excellent electrical, mechanical and optical properties of graphene. [ 14,15 ] Furthermore, graphene can be readily functionalized or modifi ed to exhibit a number of interesting electrical characteristics, [16][17][18] and resistive switching effects in some graphene based materials, for example graphene oxide, have also been reported. [19][20][21] In this study, we show that RRAM devices can be successfully integrated with graphene electrodes in a compact device structure.…”

Recent Advances in Graphene Based TiO2 Nanocomposites (GTiO2Ns) for Photocatalytic Degradation of Synthetic Dyes

“…Ramesh Raliya et al [165] also prepared nanomaterial/composite solutions by mixing GO at different concentration ratios to TiO 2 and tested their effects on photocatalytic performance. However, with ex situ hybridization, in some cases it is possible to obtain a low-density and non-uniform coverage of nanostructures by G sheets [113,[166][167][168][169].…”