{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:33:54Z","timestamp":1760142834109,"version":"build-2065373602"},"reference-count":35,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2024,1,4]],"date-time":"2024-01-04T00:00:00Z","timestamp":1704326400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>Cobalt-doped alumina catalysts were prepared using different methods, either conventional wet impregnation (WI) and\/or advanced spray impregnation (SI), and they were evaluated as novel oxidation catalysts for CO and MeOH oxidation. The spray impregnation technique was used with the aim of achieving the synthesis of core\u2013shell catalytic nanostructures to secure the chemical\/thermal stability of active sites on the catalyst carrier. The catalysts were further promoted with a low Pd content (0.5 wt.%) incorporated via either incipient wetness impregnation (DI) or spray impregnation. The results revealed the superior performance of the spray-impregnated catalysts (Co\/\u03b3-Al2O3-SI) for both reactions. The deposition of Co oxide on the outer surface of the alumina particle (SEM images) and the availability of the active Co phase resulted in the enhancement of the Co\/\u03b3-Al2O3 catalysts\u2019 oxidation activity. Pd incorporation increased the catalysts\u2019 reducibility (TPR-H2) and improved the catalysts\u2019 performance for both reactions. However, the Pd incorporation method affected the catalytic performance; with the SI method, the active phase of Co3O4 was probably covered with PdO and was not available for the oxidation reactions. On the contrary, the incorporation of Pd with the DI method resulted in a better dispersion of PdO all over the Co\/Al catalyst surface, maintaining available Co active sites and a better Pd-Co interaction. MeOH desorption studies revealed the methanol oxidation mechanism: the Co\/Al catalysts promoted the partial oxidation of MeOH to formaldehyde (HCHO) and dehydration to dimethyl ether (DME), while the Pd-based Co\/Al catalysts enhanced the complete oxidation of methanol to CO2 and H2O.<\/jats:p>","DOI":"10.3390\/nano14010124","type":"journal-article","created":{"date-parts":[[2024,1,4]],"date-time":"2024-01-04T04:05:38Z","timestamp":1704341138000},"page":"124","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Novel Nanostructured Pd\/Co-Alumina Materials for the Catalytic Oxidation of Atmospheric Pollutants"],"prefix":"10.3390","volume":"14","author":[{"given":"Eleni F.","family":"Iliopoulou","sequence":"first","affiliation":[{"name":"Chemical Process and Energy Resources Institute, Centre for Research and Technology Hellas (CPERI), CERTH, Thermi, GR-57001 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eleni","family":"Pachatouridou","sequence":"additional","affiliation":[{"name":"Chemical Process and Energy Resources Institute, Centre for Research and Technology Hellas (CPERI), CERTH, Thermi, GR-57001 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Angelos A.","family":"Lappas","sequence":"additional","affiliation":[{"name":"Chemical Process and Energy Resources Institute, Centre for Research and Technology Hellas (CPERI), CERTH, Thermi, GR-57001 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,1,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3607","DOI":"10.1016\/j.scitotenv.2010.03.046","article-title":"Carbonyl compound emissions from passenger cars fueled with methanol\/gasoline blends","volume":"408","author":"Zhao","year":"2010","journal-title":"Sci. Total Environ."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Su, S., Ge, Y., Wang, X., Zhang, M., Hao, L., Tan, J., Shi, F., Guo, D., and Yang, Z. (2020). Evaluating the in-service emissions of high-mileage dedicated methanol-fueled passenger cars: Regulated and unregulated emissions. Energies, 13.","DOI":"10.3390\/en13112680"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"65","DOI":"10.1016\/j.materresbull.2014.11.025","article-title":"On the promoting effect of the addition of CexZr1\u2212xO2 to palladium-based alumina catalysts for methanol deep oxidation","volume":"62","author":"Luo","year":"2015","journal-title":"Mater. Res. Bull."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"526","DOI":"10.1021\/ie00027a009","article-title":"Mixture Effects and Methanol Oxidation Kinetics over a Palladium Monolith Catalyst","volume":"33","author":"Brewer","year":"1994","journal-title":"Ind. Eng. Chem. Res."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"73","DOI":"10.1016\/S0166-9834(00)80045-7","article-title":"Exhaust-Catalyst Development for Methanol Fueled Vehicles III. Formaldehyde Oxidation","volume":"44","author":"McCabe","year":"1988","journal-title":"Appl. Catal."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1016\/j.cattod.2009.03.007","article-title":"Catalytic combustion of VOCs on non-noble metal catalysts","volume":"148","author":"Li","year":"2009","journal-title":"Catal. Today"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2649","DOI":"10.1039\/C4CY01733A","article-title":"Low temperature catalytic oxidation of volatile organic compounds: A review","volume":"5","author":"Huang","year":"2015","journal-title":"Catal. Sci. Technol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"325","DOI":"10.1016\/S0926-3373(03)00101-2","article-title":"Toluene combustion over palladium supported on various metal oxide supports","volume":"44","author":"Okumura","year":"2003","journal-title":"Appl. Catal. B Environ."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"937","DOI":"10.1007\/s10562-016-1713-x","article-title":"Silver\u2013Alumina Catalysts for Low-Temperature Methanol Incineration","volume":"146","author":"Nocun","year":"2016","journal-title":"Catal. Lett."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"144","DOI":"10.1016\/j.apcatb.2011.02.019","article-title":"Cu\u2013Mn and Co\u2013Mn catalysts synthesized from hydrotalcites and their use in the oxidation of VOCs","volume":"104","author":"Aguilera","year":"2011","journal-title":"Appl. Catal. B Environ."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Ga\u00e1lov\u00e1, J., and Topka, P. (2021). Gold and Ceria as Catalysts for VOC Abatement: A Review. Catalysts, 11.","DOI":"10.3390\/catal11070789"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"73935","DOI":"10.1007\/s11356-022-20535-0","article-title":"Effect of modified CeO2 on the performance of PdCu\/Ce1\u2212xTixO2 catalyst for methanol purification","volume":"29","author":"Li","year":"2022","journal-title":"Environ. Sci. Pollut. Res. Int."},{"key":"ref_13","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"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"128922","DOI":"10.1016\/j.matlet.2020.128922","article-title":"High CO reactivity of cobalt oxide catalyst deposited on alumina powders by rotary chemical vapor deposition","volume":"284","author":"Hattori","year":"2021","journal-title":"Mater. Lett."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"100198","DOI":"10.1016\/j.mtchem.2019.100198","article-title":"The catalytic activity of cobalt nanoparticles for low-temperature oxidation of carbon monoxide","volume":"14","author":"Dey","year":"2019","journal-title":"Mater. Today Chem."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"330","DOI":"10.1016\/j.apsusc.2018.05.103","article-title":"Reduction-oxidation pretreatment enhanced catalytic performance of Co3O4\/Al2O3 over CO oxidation","volume":"453","author":"Yang","year":"2018","journal-title":"Appl. Surf. Sci."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"118398","DOI":"10.1016\/j.apcata.2021.118398","article-title":"Comparisons on thermal and water-resistance of Ru and Pd supported on cobalt-doped alumina nanosheets for catalytic combustion of propane","volume":"628","author":"Yan","year":"2021","journal-title":"Appl. Catal. A"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"486","DOI":"10.1021\/acsanm.9b02056","article-title":"Size-Controlled Pd Nanoparticles Loaded on Co3O4 Nanoparticles By Calcination for Enhanced CO Oxidation","volume":"3","author":"Huang","year":"2020","journal-title":"ACS Appl. Nano Mater."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"8976","DOI":"10.1021\/acs.jpcc.8b01095","article-title":"PdCu alloy lower-like nanocages with high electrocatalytic performance for methanol oxidation","volume":"16","author":"Chen","year":"2018","journal-title":"J. Phys. Chem. C"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"2652","DOI":"10.1039\/D0CY02339F","article-title":"Applications of bimetallic PdCu catalysts","volume":"11","author":"Gholinejad","year":"2021","journal-title":"Catal. Sci. Technol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1016\/S0169-4332(99)00073-2","article-title":"Inhibition of carbon monoxide on methanol oxidation over g-alumina supported Ag, Pd and Ag\u2013Pd catalysts","volume":"147","author":"Wang","year":"1999","journal-title":"Appl. Surf. Sci."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"329","DOI":"10.1016\/j.cej.2014.12.099","article-title":"On the development of active and stable Pd\u2013Co\/\u03b3-Al2O3 catalyst for complete oxidation of methane","volume":"266","author":"Stefanov","year":"2015","journal-title":"Chem. Eng. J."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"443","DOI":"10.1021\/ef201540h","article-title":"Pd\u2212Co Coating onto Cordierite Monoliths as Structured Catalysts for Methane Catalytic Combustion","volume":"26","author":"Li","year":"2012","journal-title":"Energy Fuels"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"3693","DOI":"10.1039\/C5CY00425J","article-title":"Catalytic behaviors of Ni\/\u03b3-Al2O3 and Co\/\u03b3-Al2O3 during the hydrodeoxygenation of palm oil","volume":"5","author":"Srifa","year":"2015","journal-title":"Catal. Sci. Technol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"999","DOI":"10.1007\/s11244-022-01724-0","article-title":"Exploring Synthesis Approaches of Co based Catalysts for the Efficient Oxidation of CH4 and CO","volume":"66","author":"Iliopoulou","year":"2022","journal-title":"Top. Catal."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1","DOI":"10.5897\/JPTAF2015.0122","article-title":"Temperature programme reduction (TPR) studies of cobalt phases in alumina supported cobalt catalysts","volume":"7","author":"James","year":"2016","journal-title":"J. Petrol. Technol. Altern. Fuels"},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Ma, W., Jacobs, G., Shafer, W.D., Ji, Y., Klettlinger, J.L.S., Khalid, S., Hopps, S.D., and Davis, B.H. (2019). Fischer-Tropsch Synthesis: Cd, In and Sn Effects on a 15%Co\/Al2O3 Catalyst. Catalysts, 9.","DOI":"10.3390\/catal9100862"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"11978","DOI":"10.1016\/j.fuel.2020.119780","article-title":"A novel and facile strategy to decorate Al2O3 as an effective support for Co-based catalyst in Fischer-Tropsch synthesis","volume":"289","author":"Guo","year":"2021","journal-title":"Fuel"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"946","DOI":"10.1002\/cjce.20595","article-title":"Co\u2013Pd\/\u03b3-Al2O3 Catalyst for Heavy Oil Upgrading: Desorption Kinetics, Reducibility and Catalytic Activity","volume":"90","author":"Hossain","year":"2011","journal-title":"Can. J. Chem."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"229","DOI":"10.1007\/s10562-005-5861-7","article-title":"Reaction performance and characterization of Co\/Al2O3 Fischer\u2013Tropsch catalysts promoted with Pt, Pd and Ru","volume":"102","author":"Xu","year":"2005","journal-title":"Catal. Lett."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"72","DOI":"10.1016\/j.apcatb.2013.05.003","article-title":"Well-dispersed palladium supported on ordered mesoporous Co3O4 for catalytic oxidation of o-xylene Applied","volume":"142\u2013143","author":"Wang","year":"2013","journal-title":"Catal. B Environ."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"311","DOI":"10.1016\/S0169-4332(98)00351-1","article-title":"Effect of the acid\u2013base properties of Pd\u2013Ca\/Al2O3 catalysts on the selective hydrogenation of phenol to cyclohexanone: FT-IR and TPD characterization","volume":"136","author":"Scire","year":"1998","journal-title":"Appl. Surf. Sci."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"137","DOI":"10.1023\/A:1016715520904","article-title":"Methanol: A \u201csmart\u201d chemical probe molecule","volume":"75","author":"Badlani","year":"2001","journal-title":"Catal. Lett."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"309","DOI":"10.1016\/j.jcat.2009.11.013","article-title":"Methanol oxidation over model cobalt catalysts: Influence of the cobalt oxidation state on the reactivity","volume":"269","author":"Zafeiratos","year":"2010","journal-title":"J. Catal."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"136","DOI":"10.1016\/j.apcatb.2012.11.043","article-title":"Methanol dehydration to dimethylether over Al2O3 catalysts","volume":"145","author":"Akarmazyana","year":"2014","journal-title":"Appl. Catal. B Environ."}],"container-title":["Nanomaterials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2079-4991\/14\/1\/124\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T13:39:50Z","timestamp":1760103590000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2079-4991\/14\/1\/124"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,1,4]]},"references-count":35,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2024,1]]}},"alternative-id":["nano14010124"],"URL":"https:\/\/doi.org\/10.3390\/nano14010124","relation":{},"ISSN":["2079-4991"],"issn-type":[{"type":"electronic","value":"2079-4991"}],"subject":[],"published":{"date-parts":[[2024,1,4]]}}}