Improvement of CO2 response: Effect of SnO2 and Ni-doped SnO2 semiconductors on HPTS-basedprobes

Zeyrek Ongun M., Oğuzlar S.

4th International Eurasian Conference on Science, Engineering and Technology (EurasianSciEnTech 2022), Ankara, Turkey, 14 December 2022, (Summary Text)

  • Publication Type: Conference Paper / Summary Text
  • City: Ankara
  • Country: Turkey
  • Dokuz Eylül University Affiliated: Yes

Abstract

Accurate, continuous and precise monitoring of dissolved and gaseous carbondioxide (CO2) is vital in industrial, chemical, medical and atmospheric analysis. In this study, SnO2 and Ni-doped SnO2 powders were added as additives to increase gas sensitivity to 8-hydroxypyrene-1,3,6-trisulfonic acid (HPTS) dye, which is a commercial fluorescent indicator with high sensitivity to CO2 gas. Characterizations of synthesized metal oxide semiconductors (MOSs) were performed using photoluminescence spectroscopy (PL), X-ray photoelectron spectroscopy (XPS), X-ray diffraction spectroscopy (XRD) and scanning electron microscope (SEM). HPTS-based thin films were prepared by immobilizing dye and MOSs additives to ethyl cellulose (EC) matrix. Steady-state measurements, decay time kinetics and kinetic measurements of the sensor agents were measured in the concentration range of 0-100% [CO2]. The addition of SnO2-based semiconductors to the HPTS-based composites has resulted in many improvements in sensor dynamics such as higher sensitivity, relative signal variation and larger linear response range according to the additive-free form. The CO2 sensitivities of HPTS dye were measured as 4.7, 12.6 and 57.5 fold for the undoped and SnO2 and Ni-doped SnO2 doped forms, respectively. The response and recovery times of the HPTS-based sensing slide against CO2 with Ni-doped SnO2 powders were measured as 38 and 156 s. These results make the HPTS fluorophore with SnO2 and Ni-doped SnO2 additives into more advanced sensor agents for sensitivity to CO2 gas and show it as a promising candidate for CO2 probes.