Dispensing Single Drops as Electrochemical Reactors. Issue 8 (15th February 2022)

• Record Type: Journal Article
• Authors: Rastgar, Shokoufeh; Pleis, Sebastian; Zhang, Yanzhen; Wittstock, Gunther
• Is Part Of: ChemElectroChem. Volume 9:Issue 8(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-02-15
• Subjects: electron transfer -- ionic liquids -- femtoliter reactor -- bulk electrolysis; Electrochemistry -- Periodicals; 541.37
• DOI: 10.1002/celc.202200004
• Languages: English
• ISSNs: 2196-0216

Abstract

Abstract: A strategy is proposed to generate single microdrops with femtoliter to microliter volumes as a liquid reactor and to guide them towards a reactive surface within a viscous carrier liquid. Reactions of the drop content with the surface are exemplified by exhaustive electrolysis of the reactor content, making use of an ion‐conducting pathway through the carrier liquid. The mechanisms by which the redox‐active species from the aqueous drop reach the electrode surface were established by a combination of time‐lapse microscopy of the drop shape, chronoamperometric recording of the single drop electrolysis, and modelling of the reaction‐transport problem, showing that partitioning over the liquid‐liquid interface must be a key step in this mechanism. The possibilities of reagent delivery and external triggering of a reaction are expanded by the possibility for controlled addition of further dissolved reactants to the liquid microreactor. Abstract : Drop by drop : Droplets with volumes between fL to μL are generated as liquid reactors in a viscous carrier liquid and guided to the surface of a microelectrode. The analysis of the current transients for a complete electrolysis of the reactor content allowed to reconstruct the mechanisms by which the reactor interacts with the surface.