Visible Light‐Driven p-Type Semiconductor Gas Sensors Based on CaFe2O4 Nanoparticles

In this work, we present conductometric gas sensors based on p-type calcium iron oxide (CaFe2O4) nanoparticles. CaFe2O4 is a metal oxide (MOx) with a bandgap around 1.9 eV making it a suitable candidate for visible light-activated gas sensors. Our gas sensors were tested under a reducing gas (i.e.,...

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Detalles Bibliográficos
Autores: Qomaruddin, Casals Guillén, Olga, Utka, Andris, Granz, Tony, Waag, Andreas, Wasisto, Hutomo Suryo, Prades García, Juan Daniel, Fàbrega Gallego, Cristian
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2020
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/159219
Acceso en línea:https://hdl.handle.net/2445/159219
Access Level:acceso abierto
Palabra clave:Òxid de ferro
Calcita
Òxids metàl·lics
Díodes electroluminescents
Alcohol
Ferric oxide
Calcite
Metallic oxides
Light emitting diodes
Descripción
Sumario:In this work, we present conductometric gas sensors based on p-type calcium iron oxide (CaFe2O4) nanoparticles. CaFe2O4 is a metal oxide (MOx) with a bandgap around 1.9 eV making it a suitable candidate for visible light-activated gas sensors. Our gas sensors were tested under a reducing gas (i.e., ethanol) by illuminating them with different light-emitting diode (LED) wavelengths (i.e., 465-640 nm). Regardless of their inferior response compared to the thermally activated counterparts, the developed sensors have shown their ability to detect ethanol down to 100 ppm in a reversible way and solely with the energy provided by an LED. The highest response was reached using a blue LED (465 nm) activation. Despite some responses found even in dark conditions, it was demonstrated that upon illumination the recovery after the ethanol exposure was improved, showing that the energy provided by the LEDs is sufficient to activate the desorption process between the ethanol and the CaFe2O4 surface.