Robust Ni/ZrO 2 Catalyst Prepared by Sol‐Gel Method for Hydrogen Production from Ammonia Decomposition and Dry Reforming of Methane

Abstract With the growing challenges of global energy demand and environmental protection, hydrogen production has emerged as a key research focus. A robust Ni/ZrO 2 catalyst has demonstrated favorable catalytic activity and stability for hydrogen production via ammonia decomposition and dry reforming of methane (DRM) reactions at relatively low reaction temperatures. The reduced Ni/ZrO 2 catalyst showed a mean ammonia conversion value of 72.9% at 600 °C and could be kept for over 60‐h for ammonia decomposition reaction with a gas hourly space velocity (GHSV) of 20,000 mL·g −1 ·h −1 . In addition, the Ni/ZrO 2 catalyst exhibited a mean CO 2 conversion value of 85.1%, and H 2 /CO ratio of 1.05 at 800 °C, and could be kept for 75‐h for DRM reaction with a GHSV of 68,000 mL·g −1 ·h −1 . Structural characterization revealed that the phase transformation of ZrO 2 from cubic to monoclinic contributed to the enhanced catalyst stability. Additionally, the mesoporous structure facilitated mass transfer, while the strong metal‐support interactions suppressed Ni sintering. Notably, active carbon whiskers formed during DRM further stabilized the catalyst. These findings highlight the role of metal‐support interactions and structural evolution in enhancing the catalytic performance and long‐term stability of Ni/ZrO 2 , making it a promising candidate for high‐temperature catalytic applications.