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. 2024 Apr 18;24(8):2599.
doi: 10.3390/s24082599.

Co3O4-Based Materials as Potential Catalysts for Methane Detection in Catalytic Gas Sensors

Affiliations

Co3O4-Based Materials as Potential Catalysts for Methane Detection in Catalytic Gas Sensors

Olena Yurchenko et al. Sensors (Basel). .

Abstract

The present work deals with the development of Co3O4-based catalysts for potential application in catalytic gas sensors for methane (CH4) detection. Among the transition-metal oxide catalysts, Co3O4 exhibits the highest activity in catalytic combustion. Doping Co3O4 with another metal can further improve its catalytic performance. Despite their promising properties, Co3O4 materials have rarely been tested for use in catalytic gas sensors. In our study, the influence of catalyst morphology and Ni doping on the catalytic activity and thermal stability of Co3O4-based catalysts was analyzed by differential calorimetry by measuring the thermal response to 1% CH4. The morphology of two Co3O4 catalysts and two NixCo3-xO4 with a Ni:Co molar ratio of 1:2 and 1:5 was studied using scanning transmission electron microscopy and energy dispersive X-ray analysis. The catalysts were synthesized by (co)precipitation with KOH solution. The investigations showed that Ni doping can improve the catalytic activity of Co3O4 catalysts. The thermal response of Ni-doped catalysts was increased by more than 20% at 400 °C and 450 °C compared to one of the studied Co3O4 oxides. However, the thermal response of the other Co3O4 was even higher than that of NixCo3-xO4 catalysts (8% at 400 °C). Furthermore, the modification of Co3O4 with Ni simultaneously brings stability problems at higher operating temperatures (≥400 °C) due to the observed inhomogeneous Ni distribution in the structure of NixCo3-xO4. In particular, the NixCo3-xO4 with high Ni content (Ni:Co ratio 1:2) showed apparent NiO separation and thus a strong decrease in thermal response of 8% after 24 h of heat treatment at 400 °C. The reaction of the Co3O4 catalysts remained quite stable. Therefore, controlling the structure and morphology of Co3O4 achieved more promising results, demonstrating its applicability as a catalyst for gas sensing.

Keywords: catalyst; catalytic sensors; cobalt oxide; morphology.

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Conflict of interest statement

The authors declare no conflicts of interest.

Figures

Figure 1
Figure 1
XRD patterns of (a) undoped mCo3O4 and sCo3O4 oxides as well as (b) Ni-doped oxides NiCo2O4 and Ni0.5Co2.5O4; the reference data are listed below.
Figure 2
Figure 2
XRD patterns of the dried and calcined sCo3O4 oxides in comparison; the reference data are listed below.
Figure 3
Figure 3
SE-STEM images of (a) mCo3O4; (b) sCo3O4; (c) NiCo2O4; (d) Ni0.5Co2.5O4 metal-oxides.
Figure 4
Figure 4
SE-STEM (a,c) and HAADF-STEM (b,d) images in comparison with mCo3O4 (a,b) and sCo3O4 (c,d).
Figure 5
Figure 5
SE-STEM (a,c) and HAADF-STEM (b,d) images in comparison with NiCo2O4 (a,b) and Ni0.5Co2.5O4 (c,d).
Figure 6
Figure 6
EDX analysis of Co3O4 catalysts: HAADF-STEM images of mCo3O4 (a) and sCo3O4 (d); the corresponding elemental distribution maps of Co (b,e) and O (c,f) in respective metal-oxides.
Figure 7
Figure 7
EDX analysis of NiCo2O4 catalyst: (a) HAADF-STEM image; (b) overlay of the elemental distribution maps of Ni and Co; the elemental distribution maps of Co (c), Ni (d), and O (e).
Figure 8
Figure 8
EDX analysis of Ni0.5Co2.5O4 catalyst: (a) HAADF-STEM image; (b) overlay of the elemental distribution maps of Ni and Co; the elemental distribution of Co (c), Ni (d), and O (e).
Figure 8
Figure 8
EDX analysis of Ni0.5Co2.5O4 catalyst: (a) HAADF-STEM image; (b) overlay of the elemental distribution maps of Ni and Co; the elemental distribution of Co (c), Ni (d), and O (e).
Figure 9
Figure 9
Temperature-dependent DSC response of the four investigated catalysts to 1% CH4, with error bars giving the standard deviation from three measurements.
Figure 10
Figure 10
Results of the stability investigations: temperature-dependent DSC response of two Co3O4 catalysts to 1% methane measured before and after treatment at 400 °C (a) and at 450 °C (b).
Figure 11
Figure 11
Results of the stability investigations: temperature-dependent DSC response of two NixCo3−xO4 catalysts to 1% methane measured before and after treatment at 400 °C (a) and at 450 °C (b).
Figure 12
Figure 12
Effect of calcination temperature on the temperature-dependent DSC signal to 1% methane, demonstrated for sCo3O4.

References

    1. Bársony I., Ádám M., Fürjes P., Lucklum R., Hirschfelder M., Kulinyi S., Dücső C. Efficient catalytic combustion in integrated micropellistors. Meas. Sci. Technol. 2009;20:124009. doi: 10.1088/0957-0233/20/12/124009. - DOI
    1. Szulczyński B., Gębicki J. Currently Commercially Available Chemical Sensors Employed for Detection of Volatile Organic Compounds in Outdoor and Indoor Air. Environments. 2017;4:21. doi: 10.3390/environments4010021. - DOI
    1. Roslyakov I., Kolesnik I., Evdokimov P., Skryabina O., Garshev A., Mironov S., Stolyarov V., Baranchikov A., Napolskii K. Microhotplate catalytic sensors based on porous anodic alumina: Operando study of methane response hysteresis. Sens. Actuators B. 2021;330:129307. doi: 10.1016/j.snb.2020.129307. - DOI
    1. Samotaev N., Pisliakov A., Gorshkova A., Dzhumaev P., Barsony I., Ducso C., Biro F. Al2O3 nanostructured gas sensitive material for silicon based low power thermocatalytic sensor. Mater. Today Proc. 2020;30:443–447. doi: 10.1016/j.matpr.2019.12.393. - DOI
    1. Lorenzo-Bayona J.L., León D., Amez I., Castells B., Medic L. Experimental Comparison of Functionality between the Main Types of Methane Measurement Sensors in Mines. Energies. 2023;16:2207. doi: 10.3390/en16052207. - DOI

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