{"title":"MnO2和掺杂锰基催化剂增强甲醛氧化:机理和性能的实验和理论见解","authors":"Yuping Huang, Xinwei Zhu, Denghui Wang, Shien Hui","doi":"10.1016/j.envres.2023.117265","DOIUrl":null,"url":null,"abstract":"<div><p>Thermal catalytic degradation of formaldehyde (HCHO) over manganese-based catalysts is garnering significant attention. In this study, both theoretical simulations and experimental methods were employed to elucidate the primary reaction pathways of HCHO on the MnO<sub>2</sub>(110) surface. Specifically, the effects of doping MnO<sub>2</sub> with elements such as Fe, Ce, Ni, Co, and Cu on the HCHO oxidation properties were evaluated. Advanced characterization techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), and X-ray photoelectron spectroscopy (XPS), were employed to discern the physical properties and chemical states of the active components on the catalyst surface. The comprehensive oxidation pathway of HCHO on the MnO<sub>2</sub>(110) surface includes O<sub>2</sub><span> adsorption and dissociation, HCHO adsorption and dehydrogenation, CO</span><sub>2</sub> desorption, H<sub>2</sub>O formation and desorption, oxygen vacancy supplementation, and other elementary reactions. The pivotal rate-determining step was identified as the hydrogen migration process, characterized by an energy barrier of 234.19 kJ mol<sup>−1</sup>. Notably, HCHOO and *CHOO emerged as crucial intermediates during the reaction. Among the doped catalysts, Fe-doped MnO<sub>2</sub><span> outperformed its counterparts doped with Ce, Ni, Co, and Cu. The optimal degradation rate and selectivity were achieved at a molar ratio of Fe: Mn = 0.1. The superior performance of the Fe-doped MnO</span><sub>2</sub> can be ascribed to its large specific surface area, conducive pore structure for HCHO molecular transport, rich surface-adsorbed oxygen species, and a significant presence of oxygen vacancies.</p></div>","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":null,"pages":null},"PeriodicalIF":7.7000,"publicationDate":"2023-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Enhanced formaldehyde oxidation over MnO2 and doped manganese-based catalysts: Experimental and theoretical Insights into mechanism and performance\",\"authors\":\"Yuping Huang, Xinwei Zhu, Denghui Wang, Shien Hui\",\"doi\":\"10.1016/j.envres.2023.117265\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Thermal catalytic degradation of formaldehyde (HCHO) over manganese-based catalysts is garnering significant attention. In this study, both theoretical simulations and experimental methods were employed to elucidate the primary reaction pathways of HCHO on the MnO<sub>2</sub>(110) surface. Specifically, the effects of doping MnO<sub>2</sub> with elements such as Fe, Ce, Ni, Co, and Cu on the HCHO oxidation properties were evaluated. Advanced characterization techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), and X-ray photoelectron spectroscopy (XPS), were employed to discern the physical properties and chemical states of the active components on the catalyst surface. The comprehensive oxidation pathway of HCHO on the MnO<sub>2</sub>(110) surface includes O<sub>2</sub><span> adsorption and dissociation, HCHO adsorption and dehydrogenation, CO</span><sub>2</sub> desorption, H<sub>2</sub>O formation and desorption, oxygen vacancy supplementation, and other elementary reactions. The pivotal rate-determining step was identified as the hydrogen migration process, characterized by an energy barrier of 234.19 kJ mol<sup>−1</sup>. Notably, HCHOO and *CHOO emerged as crucial intermediates during the reaction. Among the doped catalysts, Fe-doped MnO<sub>2</sub><span> outperformed its counterparts doped with Ce, Ni, Co, and Cu. The optimal degradation rate and selectivity were achieved at a molar ratio of Fe: Mn = 0.1. The superior performance of the Fe-doped MnO</span><sub>2</sub> can be ascribed to its large specific surface area, conducive pore structure for HCHO molecular transport, rich surface-adsorbed oxygen species, and a significant presence of oxygen vacancies.</p></div>\",\"PeriodicalId\":312,\"journal\":{\"name\":\"Environmental Research\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":7.7000,\"publicationDate\":\"2023-09-27\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Environmental Research\",\"FirstCategoryId\":\"93\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0013935123020698\",\"RegionNum\":2,\"RegionCategory\":\"环境科学与生态学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"ENVIRONMENTAL SCIENCES\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Environmental Research","FirstCategoryId":"93","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0013935123020698","RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}
Enhanced formaldehyde oxidation over MnO2 and doped manganese-based catalysts: Experimental and theoretical Insights into mechanism and performance
Thermal catalytic degradation of formaldehyde (HCHO) over manganese-based catalysts is garnering significant attention. In this study, both theoretical simulations and experimental methods were employed to elucidate the primary reaction pathways of HCHO on the MnO2(110) surface. Specifically, the effects of doping MnO2 with elements such as Fe, Ce, Ni, Co, and Cu on the HCHO oxidation properties were evaluated. Advanced characterization techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), and X-ray photoelectron spectroscopy (XPS), were employed to discern the physical properties and chemical states of the active components on the catalyst surface. The comprehensive oxidation pathway of HCHO on the MnO2(110) surface includes O2 adsorption and dissociation, HCHO adsorption and dehydrogenation, CO2 desorption, H2O formation and desorption, oxygen vacancy supplementation, and other elementary reactions. The pivotal rate-determining step was identified as the hydrogen migration process, characterized by an energy barrier of 234.19 kJ mol−1. Notably, HCHOO and *CHOO emerged as crucial intermediates during the reaction. Among the doped catalysts, Fe-doped MnO2 outperformed its counterparts doped with Ce, Ni, Co, and Cu. The optimal degradation rate and selectivity were achieved at a molar ratio of Fe: Mn = 0.1. The superior performance of the Fe-doped MnO2 can be ascribed to its large specific surface area, conducive pore structure for HCHO molecular transport, rich surface-adsorbed oxygen species, and a significant presence of oxygen vacancies.
期刊介绍:
The Environmental Research journal presents a broad range of interdisciplinary research, focused on addressing worldwide environmental concerns and featuring innovative findings. Our publication strives to explore relevant anthropogenic issues across various environmental sectors, showcasing practical applications in real-life settings.