Graphene quantum dots as a novel sensing material for low-cost resistive and fast-response humidity sensors

A room temperature graphene quantum dots (GQDs) based sensing material for relative humidity monitoring is presented. GQDs are synthesized by pyrolysis of citric acid and are deposited on a metallic interdigitated microelectrodes by drop-casting technology. GQDs are nanosheets around 20 nm in averag...

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Detalles Bibliográficos
Autores: Ruiz Fernández, Virginia, Fernández, Iván, Carrasco, Pedro Mª, Cabañero, Germán, Grande, Hans J., Herrán, Jaime
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2015
País:España
Institución:Universidad de Burgos (UBU)
Repositorio:Repositorio Institucional de la Universidad de Burgos (RIUBU)
OAI Identifier:oai:riubu.ubu.es:10259/11062
Acceso en línea:https://hdl.handle.net/10259/11062
Access Level:acceso abierto
Palabra clave:Graphene quantum dots
Humidity sensors
Capillary condensation
Resistive device
Room temperature
Química analítica
Ciencia de materiales
Chemistry, Analytic
Materials science
Descripción
Sumario:A room temperature graphene quantum dots (GQDs) based sensing material for relative humidity monitoring is presented. GQDs are synthesized by pyrolysis of citric acid and are deposited on a metallic interdigitated microelectrodes by drop-casting technology. GQDs are nanosheets around 20 nm in average lateral size and an average height of 2.7 ± 0.9 nm. The response time is around few seconds and the sensitivity shows an exponential relation between 15 and 80% of RH, in resistive configuration device working at room temperature. The electrical changes as a function of the RH are related to the capillary condensation produced on the surface of the GQDs. Due to this physical behavior, a resistive path is formed between the microelectrodes and the condensed water vapor, and the resistivity of the system diminishes as the RH increases. A comparison on real time between the sensor developed and a commercial device corroborates the potential application of the novel sensor presented in this work.