Electrochemical impedance spectroscopy study of carbohydrate-terminated alkanethiol monolayers on nanoporous gold: Implications for pore wetting.

ABSTRACT: Electrochemical impedance spectroscopy (EIS) is used to compare the apparent electron transfer rate constant (k_app) for a series of alkanethiol and of carbohydrate-terminated alkanethiol self-assembled monolayers (SAMs) on both flat gold and on nanoporous gold (np-Au). Using the surface area for np-Au determined by oxide stripping, the values of k_app for the alkanethiol modified np-Au are initially over two orders of magnitude smaller than the values found on flat Au. This result provides evidence that the diffusing redox probe Fe(CN)₆^3-/4- only accesses a fraction of the np-Au surface after alkanethiol modification suggesting very limited wetting of the internal pores due to the hydrophobic nature of these surfaces. In contrast, fo

SUBMITTER: Sharma A 

PROVIDER: S-EPMC5388453 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature