Improving the electrical properties of graphene layers by chemical doping

Abstract

Although the electronic properties of graphene layers can be modulated by various doping techniques, most of doping methods cost degradation of structural uniqueness or electrical mobility. It is matter of huge concern to develop a technique to improve the electrical properties of graphene while sustaining its superior properties. Here, we report the modification of electrical properties of single- bi- and trilayer graphene by chemical reaction with potassium nitrate (KNO3) solution. Raman spectroscopy and electrical transport measurements showed the n-doping effect of graphene by KNO3. The effect was most dominant in single layer graphene, and the mobility of single layer graphene was improved by the factor of more than 3. The chemical doping by using KNO3 provides a facile approach to improve the electrical properties of graphene layers sustaining their unique characteristics.

Charged Carbon Nanomaterials: Redox Chemistries of Fullerenes, Carbon Nanotubes, and Graphenes

“…More recently, the inplane conductivity of individual graphene monolayers has been shown to increase upon doping, without affecting band structure. 246 Similarly, the conductivity of SWCNT bundles increases with increasing donor 247 and acceptor 248 intercalation. 180 Relatively nondoping adsorbents (e.g., aniline) may decrease conductivity, 248 likely due to separation of adjacent SWCNTs within the bundle, or additional scattering.…”

Stable and reversible doping of graphene by using KNO3 solution and photo-desorption current response

“…The doping treatments of graphene mostly showed degradation of mobility.35,52,58,59 The mobility improvement may be due to the ionic screening of charged-impurities scattering 23,60. The shift progressively increased with increased treatment time and V CNP saturated almost at -29 V after 20 min treatment.…”

“…On the other hand, surface charge transfer doping would not disturb the structure of graphene and can be performed by adsorption of different chemical species, such as metals and organic molecules [26][27][28][29]. Surface charge transfer doping by chemical species or chemical ions do not damage the band structure of graphene 23. position of pristine graphene.…”

Electro-optical interfacial effects on a graphene/π-conjugated organic semiconductor hybrid system

“…According to recent literature, the expression “graphite microplate” is the accurate term to describe a flake with tens of microns in lateral size and tens, or hundreds, of graphene layers in thickness [62–63], which is exactly the substrate we used for SPM and PL measurements. Monolayer graphene flakes, necessary for achieving the highest sensitivity in Raman experiments [47–48], were deposited on Si oxide or quartz substrates, whereas graphite microplate substrates, used in SPM and PL experiments, were deposited on and electrically connected to Ag-coated metallic substrates. The SPM measurements were performed using a Nanoscope V MultiMode SPM from Bruker and morphological characterization was carried out in either peak force or tapping mode.…”