Projects per year
Surprisingly few details have been reported in the literature that help the experimentalist to determine the conditions necessary for the preparation of self-assembled monolayers on graphene with a high surface coverage. With a view to graphene-based sensing arrays and devices and, in particular, in view of graphene-based varactors for gas sensing, graphene was modified in this work by the π-πinteraction-driven self-assembly of 10 pyrene and cyclodextrin derivatives from solution. The receptor compounds were pyrene, pyrene derivatives with hydroxyl, carboxyl, ester, ammonium, amino, diethylamino, and boronic acid groups, and perbenzylated α-, β-, and γ-cyclodextrins. Adsorption of these compounds onto graphene was quantified by contact-angle measurements and X-ray photoelectron spectroscopy. Data thus obtained were fitted with the Langmuir adsorption model to determine the equilibrium constants for surface adsorption and the concentrations of self-assembly solutions needed to form dense monolayers on graphene. The equilibrium constants of all pyrene derivatives fell into the range from 103.4 to 104.6 M-1. For the perbenzylated α-, β-, and γ-cyclodextrins, the equilibrium constants are 103.24, 102.97, and 102.95 M-1, respectively. Monolayers of 1-pyrenemethylammonium chloride on graphene were confirmed to be stable under heating to 100 °C in a high vacuum (2 × 10-5 Torr).
- adsorption isotherm
- contact angle
- Langmuir adsorption
- surface modification
- X-ray photoelectron spectroscopy
FingerprintDive into the research topics of 'Noncovalent Monolayer Modification of Graphene Using Pyrene and Cyclodextrin Receptors for Chemical Sensing'. Together they form a unique fingerprint.
- 2 Finished