Ion-Transfer Electrochemistry at Arrays of Nanointerfaces between Immiscible Electrolyte Solutions Confined within Silicon Nitride Nanopore Membranes
MetadataShow full item record
Ion transfer across interfaces between immiscible liquids provides a means for the nonredox electrochemical detection of ions. Miniaturization of such interfaces brings the benefits of enhanced mass transport. Here, the electrochemical behavior of geometrically regular arrays of nanoscale interfaces between two immiscible electrolyte solutions (nanoITIES arrays) is presented. These were prepared by supporting the two electrolyte phases within silicon nitride membranes containing engineered arrays of nanopores. The nanoITIES arrays were characterized by cyclic voltammetry of the interfacial transfer of tetraethylammoniumcation (TEA+) between the aqueous phase and the gelled organic phase. Effects of poreradius, pore center-to-center separation, and number of pores in the array were examined. The ion transfer produced apparent steady-state voltammetry on the forward and reverse sweeps at all experimentally accessible scan rates and at all nanopore array designs. However, background-subtraction of the voltammograms revealed the evolution of a peak-shaped response on the reverse sweep with increasing scan rate, indicative of pores filled with the organic phase to acertain extent. The steady-state voltammetric behavior at the nanoITIES arrays on the forward sweep for arrays with significant diffusion zone overlap between adjacent nanoITIES is indicative of the dominance of radial diffusion to interfaces at the edge of the arrays over linear diffusion to interfaces within the arrays. This implies that nanoITIES arrays, which occupy an overall area of micrometer dimensions, behave like a single μITIES of corresponding area to the nanoITIES array.
Showing items related by title, author, creator and subject.
Electrochemical Characterisation of Nanoscale Liquid | Liquid Interfaces Located at Focused Ion Beam-Milled Silicon Nitride MembranesSairi, M.; Chen-Tan, Nigel; Neusser, G.; Kranz, C.; Arrigan, Damien (2015)The electrochemical behaviour of single and arrayed nanoscale interfaces between two immiscible electrolyte solutions (single and array nanoITIES) is presented. The interfaces were formed at nanopores fabricated through ...
Liu, Yang; Sairi, M.; Neusser, G.; Kranz, C.; Arrigan, Damien (2015)In this work, independent radial diffusion at arrayed nanointerfaces between two immiscible electrolyte solutions (nanoITIES) was achieved. The arrays were formed at nanopores fabricated by focused ion beam milling of ...
Liu, Yang; Strutwolf, J.; Arrigan, Damien (2015)In this work, the ion-transfer voltammetric detection of the protonated β-blocker propranolol was explored at arrays of nanoscale interfaces between two immiscible electrolyte solutions (ITIES). Silicon nitride nanoporous ...