2 research outputs found
Adsorption Studies at the Graphene Oxide–Liquid Interface: A Molecular Dynamics Study
The adsorption of organic aromatic molecules, namely
aniline, onto
graphene oxide is investigated using molecular simulations. The effect
of the oxidation level of the graphene oxide sheet as well as the
presence of two different halide salts, sodium chloride and sodium
iodide, were examined. The aniline molecule in the more-reduced graphene
oxide case, in the absence of added salt, showed a slightly greater
affinity for the graphene oxide–water interface as compared
to the oxidized form. The presence of the iodide ion increased the
affinity of the aniline molecule in the reduced case but had the opposite
effect for the more-oxidized form. The effect of oxidation and added
salt on the interfacial water layer was also examined
Hosting Adamantane in the Substrate Pocket of Laccase: Direct Bioelectrocatalytic Reduction of O<sub>2</sub> on Functionalized Carbon Nanotubes
We
report the efficient immobilization and orientation of laccase from <i>Trametes versicolor</i> on MWCNT electrodes using 1-pyrenebutyric
acid adamantyl amide as a supramolecular linker. We demonstrate the
ability of adamantane to specifically interact with the hydrophobic
cavity of laccase, while pyrene interacts with MWCNT sidewalls by
π–π interactions. Adamantane allows the oriented
immobilization of laccases on MWCNT electrodes. Using an anthraquinone-modified
pyrene derivative for comparison, adamantane-modified MWCNTs achieve
the stable immobilization and orientation of a higher number of enzymes
per surface units, as confirmed by electrochemistry, theoretical calculations,
and quartz crystal microbalance experiments. Furthermore, the efficient
direct electron transfer ensures bioelectrocatalytic oxygen reduction
at high half-wave potential of 0.55 V vs SCE accompanied by no kinetic
limitation by the heterogeneous electron transfer and maximum current
densities of 2.4 mA cm<sup>–2</sup>