Description of solution

Researchers from ICIQ and URV prepared a new sensor based on multi wall carbon nanotubes (MWCNTs) treated with oxygen plasma and decorated with gold nanoparticles whose surface was functionalized by deep cavitands functionalized with quinoxaline walls. The mechanism of detection of the benzene occurs as depicted in the image below. The sensor is based on a selective molecular receptor of benzene self-assembled onto gold nanoparticles attached to carbon nanotubes forming a resistive electrode. The encapsulation of benzene provokes a change in the shape and electrical resistivity of the carbon nanotube, wich is measured by the electrode.

Advantages and unique selling points

• Highly sensitive and selective: The sensor has showed high response to benzene even in the presence of other similar aromatics with a theoretical limit of detection (LOD) of 600 ppt.
• Low power consumption: the sensing process is reversible at room temperature with the recovery of the resistance baseline upon air flushing, which is important for low power consumption. There is no need to use expensive consumables for each measurement.
• Adaptable: It is suitable for being integrated in hand-held portable analysers, wearable detectors and semi-passive radio frequency identification tags with sensing capabilities or in the nodes of wireless sensor networks.
• Large range of potential applications: The sensor can be used in environmental monitoring, workplace safety or medical devices, among others.
• Low cost commercialization: The simple experimental set-up ensures suitability for low cost commercialization and mass production.

Collaborators

Fundació Institut Català d’Investigació Química (ICIQ), Universitat Rovira i Virgili and Institució Catalana de Recerca i Estudis Avançats (ICREA)