Impact of Chlorine Functionalization on High-Mobility Chemical Vapor Deposition Grown Graphene

Abstract

We systematically investigated plasma-based chlorination of graphene and compared its properties before and after such treatment. X-ray photoelectron spectroscopy revealed that a high Cl coverage of 45.3% (close to C2Cl), together with a high mobility of 1535 cm(2)/(V s), was achieved. The C:Cl ratio n (CnCl) can be effectively tuned by controlling the dc bias and treatment time in the plasma chamber. Chlorinated graphene field-effect transistors were fabricated, and subsequent Hall-effect measurements showed that the hole carrier concentration in the chlorinated graphene can be increased roughly by a factor of 3. Raman spectra indicated that the bonding type between Cl and graphene depends sensitively on the dc bias applied in the plasma chamber during chlorination and can therefore be engineered into different reaction regimes, such as ionic bonding, covalent bonding, and defect creation. Micro-Raman mapping showed that the plasma-based chlorination process is a uniform process on the micrometer scale.

The synthesis of carbon nanomaterials using chlorinated hydrocarbons over a Fe-Co/CaCO3 catalyst

“…as found in metal chlorides). 73,74 Unfortunately the 2p 1/2 peak associated with covalent C-Cl bonds overlaps with the 2p 3/2 associated with the presence of the chloride ion peak. Furthermore, the low concentration of the Cl in the samples generates very small peaks for Cl and this makes it difficult to quantify the amount of covalent Cl in the CNTs.…”

“…Four of these peaks are readily assigned to C sp 2 , C sp 3 , C-OH and C=O; it is possible to tentatively assign the fifth peak at 285.4 to C covalently attached to Cl. 72,73 The Cl 2p spectrum of CNTs generated from chlorinated organics ( Supplementary Figs. S5 and S6) showed two signals at 201 and 199 eV which are assigned to the 2p 1/2 and 2p 3/2 of a chloride ion (e.g.…”

Sensing at the Surface of Graphene Field‐Effect Transistors

“…[12] The broad sensing potential of graphene can only be unlocked by the introduction of sensitizer (bio)molecules and structures, e.g. various inorganic groups, [23][24][25][81][82][83][84][85][86][87][88][89][90] organic or organometallic molecules, [37,[91][92][93][94][95][96] DNAs, [97][98][99][100][101] proteins, [102] peptides, [30,31,103,104] nanoparticles, [105,106,107] and 2D heterostructure. [51,52,61,108] These molecules are able to respond chemically or physically to their nearby environment, whose responses could then be transduced into an appreciable change in the conductivity of the carbon-based honeycomb scaffold.…”

A simple and flexible route to large-area conductive transparent graphene thin-films

“…There are several approaches to tune graphene electronic transport properties and the work function, including covalent modification of graphene framework [56], deposition of metals to generate Schottky-barrier type carrier injection [55,57], and noncovalent charge-transfer complex formation [58][59][60][61][62]. Due to simplicity and controllability, we choose the latter route and investigated the influence of AuCl 3 doping on self-assembled graphene thin film conductive properties.…”