{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,9]],"date-time":"2026-06-09T07:32:04Z","timestamp":1780990324863,"version":"3.54.1"},"reference-count":38,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2024,4,18]],"date-time":"2024-04-18T00:00:00Z","timestamp":1713398400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Fraunhofer Gesellschaft","award":["03EN5009C"],"award-info":[{"award-number":["03EN5009C"]}]},{"DOI":"10.13039\/501100002347","name":"Federal Ministry of Education and Research","doi-asserted-by":"publisher","award":["03EN5009C"],"award-info":[{"award-number":["03EN5009C"]}],"id":[{"id":"10.13039\/501100002347","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>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\u2212xO4 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 \u00b0C and 450 \u00b0C compared to one of the studied Co3O4 oxides. However, the thermal response of the other Co3O4 was even higher than that of NixCo3\u2212xO4 catalysts (8% at 400 \u00b0C). Furthermore, the modification of Co3O4 with Ni simultaneously brings stability problems at higher operating temperatures (\u2265400 \u00b0C) due to the observed inhomogeneous Ni distribution in the structure of NixCo3\u2212xO4. In particular, the NixCo3\u2212xO4 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 \u00b0C. 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.<\/jats:p>","DOI":"10.3390\/s24082599","type":"journal-article","created":{"date-parts":[[2024,4,18]],"date-time":"2024-04-18T10:30:52Z","timestamp":1713436252000},"page":"2599","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Co3O4-Based Materials as Potential Catalysts for Methane Detection in Catalytic Gas Sensors"],"prefix":"10.3390","volume":"24","author":[{"given":"Olena","family":"Yurchenko","sequence":"first","affiliation":[{"name":"Fraunhofer Institute for Physical Measurement Techniques (IPM), 79110 Freiburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0608-9889","authenticated-orcid":false,"given":"Patrick","family":"Diehle","sequence":"additional","affiliation":[{"name":"Fraunhofer Institute for Microstructure of Materials and Systems (IMWS), 06120 Halle, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Frank","family":"Altmann","sequence":"additional","affiliation":[{"name":"Fraunhofer Institute for Microstructure of Materials and Systems (IMWS), 06120 Halle, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4646-8990","authenticated-orcid":false,"given":"Katrin","family":"Schmitt","sequence":"additional","affiliation":[{"name":"Fraunhofer Institute for Physical Measurement Techniques (IPM), 79110 Freiburg, Germany"},{"name":"Department of Microsystems Engineering (IMTEK), University of Freiburg, 79110 Freiburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3078-8065","authenticated-orcid":false,"given":"J\u00fcrgen","family":"W\u00f6llenstein","sequence":"additional","affiliation":[{"name":"Fraunhofer Institute for Physical Measurement Techniques (IPM), 79110 Freiburg, Germany"},{"name":"Department of Microsystems Engineering (IMTEK), University of Freiburg, 79110 Freiburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,4,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"124009","DOI":"10.1088\/0957-0233\/20\/12\/124009","article-title":"Efficient catalytic combustion in integrated micropellistors","volume":"20","author":"Lucklum","year":"2009","journal-title":"Meas. Sci. Technol."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Szulczy\u0144ski, B., and G\u0119bicki, J. (2017). Currently Commercially Available Chemical Sensors Employed for Detection of Volatile Organic Compounds in Outdoor and Indoor Air. Environments, 4.","DOI":"10.3390\/environments4010021"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"129307","DOI":"10.1016\/j.snb.2020.129307","article-title":"Microhotplate catalytic sensors based on porous anodic alumina: Operando study of methane response hysteresis","volume":"330","author":"Roslyakov","year":"2021","journal-title":"Sens. Actuators B"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"443","DOI":"10.1016\/j.matpr.2019.12.393","article-title":"Al2O3 nanostructured gas sensitive material for silicon based low power thermocatalytic sensor","volume":"30","author":"Samotaev","year":"2020","journal-title":"Mater. Today Proc."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Lorenzo-Bayona, J.L., Le\u00f3n, D., Amez, I., Castells, B., and Medic, L. (2023). Experimental Comparison of Functionality between the Main Types of Methane Measurement Sensors in Mines. Energies, 16.","DOI":"10.3390\/en16052207"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"844","DOI":"10.1016\/j.apcatb.2018.06.050","article-title":"Oxidation of residual methane from VNG vehicles over Co3O4-based catalysts: Comparison among bulk, Al2O3-supported and Ce-doped catalysts","volume":"237","author":"Choya","year":"2018","journal-title":"Appl. Catal. B Environ."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"109589","DOI":"10.1016\/j.rser.2019.109589","article-title":"A review on catalytic methane combustion at low temperatures: Catalysts, mechanisms, reaction conditions and reactor designs","volume":"119","author":"He","year":"2020","journal-title":"Renew. Sustain. Energy Rev."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"125911","DOI":"10.1016\/j.cej.2020.125911","article-title":"Reaction mechanism of propane oxidation over Co3O4 nanorods as rivals of platinum catalysts","volume":"402","author":"Ma","year":"2020","journal-title":"Chem. Eng. J."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Wang, B., Zhao, X., Zhang, Y., and Wang, Z. (2024). Research on High Performance Methane Gas Concentration Sensor Based on Pyramid Beam Splitter Matrix. Sensors, 24.","DOI":"10.3390\/s24020602"},{"key":"ref_10","unstructured":"Baker, A. (1963). Apparatus for Detecting Combustible Gases Having an Electrically Conductive Member Enveloped in a Refractory Material. (3,092,799), U.S. Patent."},{"key":"ref_11","unstructured":"White, R. (2024, February 28). The Pellistor Is Dead? Long Live the Pellistor!. Available online: www.envirotech-online.com\/article\/environmental-laboratory\/7\/sgx-sensortech\/the-pellistor-is-dead-nbsplong-live-the-pellistor\/1699."},{"key":"ref_12","unstructured":"Doncaster, A. (2021, March 18). A Discussion on Pellistor Gas Sensor Responses. Annual Buyers Guide. Available online: https:\/\/www.chromatographytoday.com\/article\/gas-detection\/8\/clairair\/a-discussion-on-pellistor-gas-sensor-responses\/467."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Florea, O.G., St\u0103noiu, A., Gheorghe, M., Cobianu, C., Nea\u0163u, F., Trandafir, M.M., Nea\u0163u, \u015e., Florea, M., and Simion, C.E. (2020). Methane Combustion Using Pd Deposited on CeOx-MnOx\/La-Al2O3 Pellistors. Materials, 13.","DOI":"10.3390\/ma13214888"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"14304","DOI":"10.1021\/acscatal.0c03338","article-title":"Low-Temperature Methane Oxidation for Efficient Emission Control in Natural Gas Vehicles: Pd and Beyond","volume":"10","author":"Jiang","year":"2020","journal-title":"ACS Catal."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"62","DOI":"10.1016\/j.apcata.2015.07.040","article-title":"Effect of Co\/Ni ratios in cobalt nickel mixed oxide catalysts on methane combustion","volume":"505","author":"Lim","year":"2015","journal-title":"Appl. Catal. A Gen."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1807519","DOI":"10.1002\/adfm.201807519","article-title":"Bowtie-Shaped NiCo2O4 Catalysts for Low-Temperature Methane Combustion","volume":"29","author":"Dai","year":"2019","journal-title":"Adv. Funct. Mater."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"4490","DOI":"10.1039\/C9RA09544F","article-title":"Combustion of lean methane over Co3O4 catalysts prepared with different cobalt precursors","volume":"10","author":"Zheng","year":"2020","journal-title":"RSC Adv."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"5570","DOI":"10.1002\/cctc.201901382","article-title":"Facet-Dependent Activity of Co3O4 Catalyst for C3H8 Combustion","volume":"11","author":"Yao","year":"2019","journal-title":"ChemCatChem"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Lin, H., Liu, Y., Deng, J., Jing, L., and Dai, H. (2023). Methane Combustion over the Porous Oxides and Supported Noble Metal Catalysts. Catalysts, 13.","DOI":"10.3390\/catal13020427"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"713","DOI":"10.1126\/science.1222887","article-title":"Exceptional activity for methane combustion over modular Pd@CeO2 subunits on functionalized Al2O3","volume":"337","author":"Cargnello","year":"2012","journal-title":"Science"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"65","DOI":"10.1038\/ncomms8798","article-title":"Understanding complete oxidation of methane on spinel oxides at a molecular level","volume":"6","author":"Tao","year":"2015","journal-title":"Nat. Commun."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"3546","DOI":"10.1039\/D0NJ06110G","article-title":"Acid etching induced defective Co3O4 as an efficient catalyst for methane combustion reaction","volume":"45","author":"Bao","year":"2021","journal-title":"New J. Chem."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"3085","DOI":"10.1039\/c3cy00193h","article-title":"Co3O4 nanocrystals and Co3O4\u2013MOx binary oxides for CO, CH4 and VOC oxidation at low temperatures: A review","volume":"3","author":"Liotta","year":"2013","journal-title":"Catal. Sci. Technol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"712","DOI":"10.1016\/j.apcatb.2017.01.055","article-title":"Optimization of Pd catalysts supported on Co3O4 for low-temperature lean combustion of residual methane","volume":"206","author":"Ercolino","year":"2017","journal-title":"Appl. Catal. B Environ."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"6404","DOI":"10.1039\/C9CY01766F","article-title":"Ultrafine PdOx nanoparticles on spinel oxides by galvanic displacement for catalytic combustion of methane","volume":"9","author":"Zhang","year":"2019","journal-title":"Catal. Sci. Technol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"604","DOI":"10.1002\/ente.201600402","article-title":"Low Temperature Complete Combustion of Lean Methane over Cobalt-Nickel Mixed-Oxide Catalysts","volume":"5","author":"Shao","year":"2017","journal-title":"Energy Technol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"150","DOI":"10.1016\/j.apcatb.2015.04.021","article-title":"Low temperature propane oxidation over Co3O4 based nano-array catalysts: Ni dopant effect, reaction mechanism and structural stability","volume":"180","author":"Ren","year":"2016","journal-title":"Appl. Catal. B Environ."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1900641","DOI":"10.1002\/ente.201900641","article-title":"Deactivation Mechanism, Countermeasures, and Enhanced CH4 Oxidation Performance of Nickel\/Cobalt Oxides","volume":"8","author":"Chen","year":"2020","journal-title":"Energy Technol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"94","DOI":"10.1016\/j.apcata.2016.07.009","article-title":"Morphology-dependent performance of Co3O4 via facile and controllable synthesis for methane combustion","volume":"525","author":"Chen","year":"2016","journal-title":"Appl. Catal. A Gen."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"14","DOI":"10.1016\/j.apsusc.2017.02.186","article-title":"Enhanced methane combustion over Co3O4 catalysts prepared by a facile precipitation method: Effect of aging time","volume":"410","author":"Pu","year":"2017","journal-title":"Appl. Surf. Sci."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"37","DOI":"10.5194\/jsss-10-37-2021","article-title":"Impact of particle size and morphology of cobalt oxide on the thermal response to methane examined by thermal analysis","volume":"10","author":"Yurchenko","year":"2021","journal-title":"J. Sens. Sens. Syst."},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Lyu, X., Yurchenko, O., Diehle, P., Altmann, F., W\u00f6llenstein, J., and Schmitt, K. (2023). Accelerated Deactivation of Mesoporous Co3O4-Supported Au\u2013Pd Catalyst through Gas Sensor Operation. Chemosensors, 11.","DOI":"10.3390\/chemosensors11050271"},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Simion, C.E., Florea, O.G., Florea, M., Nea\u0163u, F., Nea\u0163u, \u015e., Trandafir, M.M., and St\u0103noiu, A. (2020). CeO2:Mn3O4 Catalytic Micro-Converters Tuned for CH4 Detection Based on Catalytic Combustion under Real Operating Conditions. Materials, 13.","DOI":"10.3390\/ma13092196"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"9792","DOI":"10.1038\/s41598-023-36878-8","article-title":"Differential thermal analysis techniques as a tool for preliminary examination of catalyst for combustion","volume":"13","author":"Yurchenko","year":"2023","journal-title":"Sci. Rep."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"185","DOI":"10.5194\/jsss-10-185-2021","article-title":"Low-power sensor node for the detection of methane and propane","volume":"10","author":"Bierer","year":"2021","journal-title":"J. Sens. Sens. Syst."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"16136","DOI":"10.1021\/ja806400e","article-title":"Selective Synthesis of Co3O4 Nanocrystal with Different Shape and Crystal Plane Effect on Catalytic Property for Methane Combustion","volume":"130","author":"Hu","year":"2008","journal-title":"J. Am. Chem. Soc."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1049","DOI":"10.1038\/s41563-020-00805-3","article-title":"Opportunities and challenges in the development of advanced materials for emission control catalysts","volume":"20","author":"Datye","year":"2020","journal-title":"Nat. Mater."},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Sanchis, R., Garc\u00eda, A., Ivars-Barcel\u00f3, F., Taylor, S.H., Garc\u00eda, T., Dejoz, A., V\u00e1zquez, M.I., and Solsona, B. (2021). Highly Active Co3O4-Based Catalysts for Total Oxidation of Light C1-C3 Alkanes Prepared by a Simple Soft Chemistry Method: Effect of the Heat-Treatment Temperature and Mixture of Alkanes. Materials, 14.","DOI":"10.3390\/ma14237120"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/24\/8\/2599\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T14:30:13Z","timestamp":1760106613000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/24\/8\/2599"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,4,18]]},"references-count":38,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2024,4]]}},"alternative-id":["s24082599"],"URL":"https:\/\/doi.org\/10.3390\/s24082599","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,4,18]]}}}