Inverse NiAl₂O₄on LaAlO₃–Al₂O₃: Unique Catalytic Structure for Stable CO₂Reforming of Methane

Ni supported on LaAlO 3 –Al 2 O 3 (NLA) perovskite oxide was synthesized for syngas production via DRM and compared with Ni supported on γ-Al 2 O 3 (NA) and La 2 O 3 (NL). The formation of LaAlO 3 perovskite oxide structure involves interaction with octahedral sites of the alumina support, resulting in the enforced Ni–Al interaction with the underlying tetrahedral Al 3+ sites when Ni was impregnated. As a result, the inverse NiAl 2 O 4 spinel structure was formed, and it positively affects the catalytic activity. Catalytic studies show that NLA exhibited the most stable catalytic performance with the lowest carbon deposition. Furthermore, XRD of spent NA catalyst showed phase transformation of support from γ-Al 2 O 3 to α-Al 2 O 3 . Therefore, the enhanced stability of the NLA catalyst throughout the 30 h DRM reaction is attributed to the enhanced lattice stability imparted by the inverse spinel structure and LaAlO 3 nanocrystallites on the alumina support, both of which aid in minimizing agglomeration of Ni particles.