Biogas, a renewable energy source, is primarily composed of CH4 and CO2. It is a promising alternative to fossil fuels and can be used directly for electricity production as well as heat generation via combustion. Concerns about climate change and a greater emphasis on renewable energy sources have recently increased interest in biogas utilization. In this context, biogas reforming and decomposition (BRD) into synthesis gas and carbon nanofibers (CNFs) is viewed as a new and attractive way of efficiently valorising biogas. In this study, Ni-loaded (i.e., 20, 50 wt%) mesoporous alumina materials were prepared using one-pot evaporation-induced self-assembly method for BRD. Synthesized materials were characterized by various techniques: N2-physisorption, X-ray diffraction, temperature-programmed reduction, scanning electron microscopy, and thermal gravimetric analysis. Results showed that textural and structural properties of synthesised materials differed with Ni loading. High Ni-loaded catalyst displayed higher surface area, pore volume, pore size distribution, and average particle size which is the result of deposition of Ni species outside alumina grains creating thus, surface defects. BRD results were greatly influenced by Ni content with Ni50%Al2O3 reflecting catalytic behaviour similar to those expected for pure methane decomposition. Most importantly, this catalyst was also capable of generating, selectively, interesting carbon nanofibers. (c) 2022 THE AUTHORS. Published by Elsevier BV on behalf of Faculty of Engineering, Alexandria University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).