Revealing Solvent-free Solid-fed Aerosol Flame Technique to Synthesize Copper Oxide Deposited on Ceria Catalyst for Efficient CO Oxidation Applications
Year: 2026
Type: preprint
Abstract: Developing efficient technologies for CO oxidation is an urgent priority in environmental catalysis. Copper oxide deposited on cerium oxide (CuO/CeO 2 ) has attracted considerable attention as a promising non-precious-metal catalyst for low-temperature CO oxidation. Furthermore, aerosol process emerged as a scalable route to engineer CuO/CeO 2 with tailored structures and interfacial properties, however, popular vapor-fed and liquid-fed aerosol flame approaches remain constrained by precursor requirements (vapor-fed: sufficient vapor pressure; liquid-fed: precursor solubility or dispersibility in carrier solvents). Here, for the first time, we introduce solid-fed aerosol flame synthesis (SAFS) as a single-step, solvent-free route to synthesize heterostructured CuO/CeO 2 catalysts. Through selective vaporization of Cu 2 O followed by heterogeneous nucleation onto solid CeO 2 particles, SAFS produces a well-defined architecture of CuO nanoparticles intimately deposited on CeO 2 supports. By varying the flame conditions and Cu loading, we systematically investigate their effects on particle formation, interfacial properties, and catalytic performance. The highest performance catalyst, synthesized at 2 L/min-CH 4 flame with 2 wt.% Cu 2 O, exhibits the highest CO oxidation activity, achieving a CO oxidation rate of 13.73 mLCO/min·gcat and a turnover frequency of 0.026 s -1 at 120 ºC. This enhanced performance, compared to other as-prepared CuO/CeO 2 samples, arises from an optimal balance between oxygen vacancy generation and metal-support interaction achieved during the SAFS process. Here, oxygen vacancy generation is favored under fuel-rich conditions, whereas metal-support interaction decreases with CeO 2 sublimation and CuO nanoparticle sintering under elevated combustion enthalpy. These findings advance the fundamental understanding of flame-based synthesis and provide a scalable route toward high-performance, cost-effective catalysts for environmental remediation.
Source: ChemRxiv
Institution: Hiroshima University
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
Award: G7919066412
OpenAlex ID: W7216156263