Sheikh Muhammad Farhan, Longwei Cheng, Pan Wang, JianJun Yin, Zhijian Chen
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引用次数: 0
Abstract
A sustainable and cost-effective alternative for environmental applications is the use of PGM-free catalysts, which are crucial for pollutant removal. This research employed the sol-gel method to synthesize stable and effective mesoporous CeCuOx mixed oxide catalysts to facilitate the oxidation of CO and C3H6 emissions at lower temperatures. Additionally, pure CeO2 and CuO were also synthesized for comparative analysis. Catalytic performance was considerably increased by doping CeO2 with Cu, whereas pure CuO and CeO2 showed modest activity. XRD, SEM, BET, XPS, Raman spectroscopy, H2-TPR, and CO-TPD showed that increasing Ce content produced a consistent pore structure without aggregation. In contrast, higher Cu concentration resulted in bulk CuO production, which led to decreased catalytic performance. In particular, the production of isolated CuOx species partly covered or clogged pores when the Cu level was above 20 wt%, which reduced the total number of effective sites for O2 activation. Compared to other mixed and pure oxides, the ideal catalyst, Ce7Cu3Ox (T90, CO = 178 °C), showed smaller particle size, higher specific surface area, and a larger lattice oxygen species and oxygen vacancies concentration. Additionally, it showed the best CO and C3H6 conversion due to its high Ce3+ concentration and interfacial active Cu species ratio. H2-TPR and CO-TPD analyses demonstrated that Ce-Cu mixed oxides with optimal Ce/Cu ratios, particularly Ce7Cu3Ox and Ce5Cu5Ox, achieve enhanced reducibility and balanced CO adsorption, which are critical for maximizing catalytic reactivity. The catalytic activity exhibited the following sequence: Ce7Cu3Ox > Ce5Cu5Ox > Ce9Cu1Ox > Ce3Cu7Ox > Ce1Cu9Ox > CuO > CeO2. This investigation offers a valuable perspective on the mechanisms of Ce-Cu interaction, which contributes to developing high-performance CeCuOx catalysts that are free of PGMs and operate under realistic reaction conditions.
期刊介绍：
Catalysis Letters aim is the rapid publication of outstanding and high-impact original research articles in catalysis. The scope of the journal covers a broad range of topics in all fields of both applied and theoretical catalysis, including heterogeneous, homogeneous and biocatalysis.
The high-quality original research articles published in Catalysis Letters are subject to rigorous peer review. Accepted papers are published online first and subsequently in print issues. All contributions must include a graphical abstract. Manuscripts should be written in English and the responsibility lies with the authors to ensure that they are grammatically and linguistically correct. Authors for whom English is not the working language are encouraged to consider using a professional language-editing service before submitting their manuscripts.
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