Application of TiO₂ nanotubes as bulky supports of highly active CO₂ methanation catalysts prepared via the polygonal barrel-sputtering method

Herein, TiO₂ nanotubes (TiO₂-NTs) were used as bulky supports for the preparation of highly active CO₂ methanation catalysts to maintain the stability of the reaction at high gas flow rates. The nanotube shapes of the prepared TiO₂-NTs remained unchanged at a calcination temperature of 300 °C. The CO₂ methanation reaction on Ru-sputtered catalysts indicated that at high gas flow rates of 10% CO₂/Ar and H₂, some crack-like gaps were formed in the catalyst bed using raw anatase TiO₂ particle supports, whereas no gaps appeared in the case where TiO₂-NTs were used as the support, leading to a stable reaction. This result is attributed to the formation of a sparse catalyst bed owing to the bulky TiO₂-NT supports.