Many carbon nanotube (CNT) applications require precisely controlled chemical
functionalization that is minimally disruptive to electrical performance. A promising approach is
the generation of sp³ hybridized carbon atoms in the sp²-bonded lattice. We have investigated the
possibility of using a carboxylic acid functionalized diazonium reagent to introduce a defined
number...
Many carbon nanotube (CNT) applications require precisely controlled chemical
functionalization that is minimally disruptive to electrical performance. A promising approach is
the generation of sp³ hybridized carbon atoms in the sp²-bonded lattice. We have investigated the
possibility of using a carboxylic acid functionalized diazonium reagent to introduce a defined
number...
Atomically-thin graphene sheets have unprecedented characteristics for biosensing applications. These characteristics include mechanical flexibility and strength, optical transparency, electrical sensitivity and biocompatibility. The primary theme of this dissertation is the characterization and application of graphene field-effect transistors (FETs) in biologically-relevant physiological environments.Understanding the interface that forms between an electrolyte and...
To determine the thermal noise limit of graphene biotransistors, we have measured the complex impedance between the basal plane of single-layer graphene and an aqueous electrolyte. The impedance is dominated by an imaginary component but has a finite real component. Invoking the fluctuation–dissipation theorem, we determine the power spectral density...
To determine the thermal noise limit of graphene biotransistors, we have measured the complex impedance between the basal plane of single-layer graphene and an aqueous electrolyte. The impedance is dominated by an imaginary component but has a finite real component. Invoking the fluctuation–dissipation theorem, we determine the power spectral density...
Using a graphene field-effect transistor biosensor, we monitored the pH inside a living biofilm
with fast temporal resolution (~ 1 s) over multi-hour time periods. The atomically-thin sensor is
positioned between the biofilm and a supporting silicon oxide surface, providing non-invasive
access to conditions at the base of the biofilm....
Using a graphene field-effect transistor biosensor, we monitored the pH inside a living biofilm
with fast temporal resolution (~ 1 s) over multi-hour time periods. The atomically-thin sensor is
positioned between the biofilm and a supporting silicon oxide surface, providing non-invasive
access to conditions at the base of the biofilm....
Graphene is a promising material for applications in aqueous electrolyte environments. To explore the impact of such environments on graphene's electrical properties, we performed Hall bar measurements on electrolyte-gated graphene. Assuming a Drude model, we find that the room temperature carrier mobility in water-gated, SiO₂-supported graphene reaches 7000 cm²/Vs, comparable to...
Many carbon nanotube (CNT) applications require precisely controlled chemical functionalization that is minimally disruptive to electrical performance. A promising approach is the generation of sp³ hybridized carbon atoms in the sp²-bonded lattice. We have investigated the possibility of using a carboxylic acid functionalized diazonium reagent to introduce a defined number...
To determine the thermal noise limit of graphene biotransistors, we have measured the complex impedance between the basal plane of single-layer graphene and an aqueous electrolyte. The impedance is dominated by an imaginary component but has a finite real component. Invoking the fluctuation–dissipation theorem, we determine the power spectral density...