Roles of Al2O3 coating layer on an ordered mesoporous Ni/m-Al2O3 for combined steam and CO2 reforming with CH4. (1st January 2023)

• Record Type: Journal Article
• Authors: Yu, Ji Su; Park, Jae Min; Kwon, Jae Hyeon; Park, Kyung Soo; Choung, Jin Woo; Park, Myung-June; Bae, Jong Wook
• Is Part Of: Fuel. Volume 331:Part 1(2023)
• Publication Date: 2023-01-01
• Subjects: Combined steam and CO2 reforming with CH4 (CSCR) -- Overlayer Al2O3 coating -- Ordered mesoporous Al2O3 (m-Al) -- Thermal stability of Ni nanoparticles -- Resistance to coke formation; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2022.125702
• Languages: English
• ISSNs: 0016-2361

Abstract

Graphical abstract: Highlights: Spatially confined NiO with Al2 O3 overlayer on Ni/m-Al2 O3 showed a superior stability. Optimal amount of Al2 O3 layers was <3 wt% on mesoporous Ni/m-Al structures. Al2 O3 protective overlayers increased long-term stability with small cokes depositions. Abstract: To enhance catalytic and thermal stability of Ni nanoparticles for a combined steam and CO2 reforming with CH4 (CSCR), the utilization of an ordered mesoporous Al2 O3 support with ∼6 nm of average pore diameter (Ni/m-Al) was proposed in terms of spatial confinement effects of the Ni nanoparticles with the help of successive Al2 O3 overlayer protective layers (Ni/m-Al@Al). At an optimal amount of Al2 O3 coating layers less than ∼3 wt%, the much higher catalytic activity and stability were observed on the Ni/m-Al@Al(3). The synergy effects of Al2 O3 overlayers on the ordered mesoporous Ni/m-Al were mainly attributed to the formation of strongly interacted Ni-Al2 O3 interfaces as supported by its higher XPS binding energy in the spatially restricted mesoporous m-Al channels with the protective metal oxide overlayers. Those structures were also responsible for the suppressed migrations of the spatially confined Ni nanoparticles to the outer m-Al surfaces by Al2 O3 protective overlayers, which resulted in an excellent long-term stability with small coke depositions by preserving the original Ni nanoparticle sizes.