Modelling of Impulsional pH Variations Using ChemFET-Based Microdevices: Application to Hydrogen Peroxide Detection

Abdou Karim Diallo (1) , Lyas Djeghlaf (1) , Jérôme Launay (1) , Pierre Temple-Boyer (1)

1 LAAS-MICA - Équipe MICrosystèmes d'Analyse

This work presents the modelling of impulsional pH variations in microvolume related to water-based electrolysis and hydrogen peroxide electrochemical oxidation using an ElecFET (Electrochemical Field Effect Transistor) microdevice. This ElecFET device consists of a pH-ChemFET (pH-Chemical FET) with an integrated microelectrode around the dielectric gate area in order to trigger electrochemical reactions. Combining oxidation/reduction reactions on the microelectrode, water self-ionization and diffusion properties of associated chemical species, the model shows that the sensor response depends on the main influential parameters as: (i) polarization parameters on the microelectrode, i.e. voltage (V p) and time (t p), (ii) distance between the gate sensitive area and the microelectrode (d), and (iii) hydrogen peroxide concentration ([H 2 O 2 ]). The model developed can predict the ElecFET response behaviour and creates new opportunities for H 2 O 2 –based enzymatic detection of biomolecules.

Mots clés: H 2 O 2 detection; microelectrode; H 2 O electrolysis; Modelling; ChemFET

Domaines: Micro et nanotechnologies/Microélectronique; Chimie analytique

Abdou Karim Diallo, Lyas Djeghlaf, Jérôme Launay, Pierre Temple-Boyer. Modelling of Impulsional pH Variations Using ChemFET-Based Microdevices: Application to Hydrogen Peroxide Detection. Sensors, 2014, 14 (2), pp.3267-3283. ⟨10.3390/s140203267⟩. ⟨hal-01508071⟩