Molybdenum-promoted nickel catalysts for CO₂ methanation: a critical review and informetric perspective

The increasing need for sustainable energy solutions has positioned CO₂ methanation as a key technology for mitigating carbon emissions and storing renewable hydrogen as synthetic natural gas. This review bridges a significant knowledge gap by combining a critical assessment of the catalytic performance of molybdenum (Mo)-promoted nickel catalysts with an informetric analysis of research trends from 1994 to 2023. Using Web of Science, 773 publications were analyzed to identify trends, collaborations, and impactful studies. The review highlights Mo's role in enhancing catalyst stability, activity, and selectivity through properties such as improved hydrogen activation, electron transfer, and the formation of oxygen vacancies. Challenges, including sintering and coke formation, are addressed, with recommendations for optimizing catalyst design and operational conditions. This study concludes by proposing future research directions to further exploit Mo-based systems in achieving low-temperature, energy-efficient CO₂ methanation.