The development of carbon nanostructured sensors

[摘要] ENGLISH ABSTRACT: During this research the possibility of using carbon nanostructures in sensorswere investigated. Graphene and carbon nanotubes (CNTs) are the nano-structures that were used in the developed sensors. Graphene is a singleatomic layer of carbon and a carbon nanotube (CNT) is a rolled up sheet ofgraphene that forms a tube. The unique structure and incredible propertiesof both these materials make them ideal to be used in sensory applications. Agraphene sensor was developed and experiments were performed to determinewhether graphene is a viable candidate to be used in a wide range of sensoryapplications. The graphene sensor operated successfully as a humidity sensorand this led to the discovery that humidity can be used to control the bandgapin graphene. The absorption of CO2 in graphene was successfully measuredusing surface acoustic waves. As a result, any gas that graphene absorbs can bedetected using this method. The use of graphene in three liquid applicationswas tested. The graphene showed no potential to be used as a pH sensoror as a ow sensor. An experiment was undertaken to determine whethergraphene can increase the e ciency of a water electrolysis process, but itwas established that the graphene does not make a signi cant di erence. ACNT gas sensor that identi es a gas based on its ionization characteristicswas studied and designed. Due to the insu cient height of the grown CNTs,it was decided to focus on the creation of a model of the sensor that can beused to design it optimally. The results of the experiments con rmed thatcarbon nanostructures such as graphene and CNTs have potential to be usedin future sensing applications.

[发布机构] Stellenbosch University