|Title||Metal-organic polyhedra-coated si nanowires for the sensitive detection of trace explosives|
|Author(s)||Cao, Anping; Zhu, Wei; Shang, Jin; Klootwijk, Johan H.; Sudhölter, Ernst J.R.; Huskens, Jurriaan; Smet, Louis C.P.M. de|
|Source||Nano Letters 17 (2017)1. - ISSN 1530-6984 - 7 p.|
|Publication type||Refereed Article in a scientific journal|
|Keyword(s)||Charge-transfer interaction - Explosives detection - Metal-organic polyhedra - Molecular recognition - Silicon nanowire-based field-effect transistor|
Surface-modified silicon nanowire-based field-effect transistors (SiNW-FETs) have proven to be a promising platform for molecular recognition in miniature sensors. In this work, we present a novel nanoFET/device for the sensitive and selective detection of explosives based on affinity layers of metal-organic polyhedra (MOPs). The judicious selection of the \ geometric and electronic characteristics of the assembly units (organic ligands and unsaturated metal site) embedded within the MOP cage allowed for the formation of multiple charge-transfer (CT) interactions to facilitate the selective explosive inclusion. Meanwhile, the host-stabilized CT complex inside the cage acted as an effective molecular gating element to strongly modulate the electrical conductance of the silicon nanowires. By grafting the MOP cages onto a SiNW-FET device, the resulting sensor showed a good electrical sensing capability to various explosives, especially 2,4,6-trinitrotoluene (TNT), with a detection limit below the nanomolar level. Importantly, coupling MOPs-which have tunable structures and properties- to SiNW-based devices may open up new avenues for a wide range of sensing applications, addressing various target analytes.