Development of a Potentionmetric CO2 Sensor Chip Based on the Solid-Contact Ion-Selecitve Electrodes

In this study, we aimed to develop a pCO
₂
sensor based on the solid-contact ion-selective electrodes (SC-ISEs). With the thermodynamic model, a new type pCO
₂
sensor could be achieved by measuring the electromotive force (EMF) between a pH meter and a carbonate-selective electrode. We fabricated a SC pH meter (sensitivity = 45.35 mV/decade, R
²
= 99.96) and a SC carbonate-selective electrode (sensitivity = 52.78 mV/decade, R
²
= 97.55) for following pCO
₂
sensing. The results showed that the new type pCO
₂
sensor could respond to the change in dissolved CO
₂
while coupling two electrodes, and the sensitivity was 49.27 mV/decade (R
²
= 79.20).