Catalytic applications of bimetallic molybdenum nitrides in biomass conversion: Recent advances, challenges and opportunities

The current energy crisis, along with massive atmospheric CO₂ emissions caused by fossil fuel combustion, motivates researchers to search for renewable alternative energy sources with minimal climate impact. Biomass emerges as a promising low-carbon feedstock for biofuel and chemical production, though its efficient conversion requires advanced catalytic systems with high efficiency and stability. Molybdenum nitride-based catalysts, particularly bimetallic variants, have shown exceptional promise in this regard. This study performed a PRISMA systematic review of recent advances in molybdenum nitrides catalysts for biomass conversion, covering the synthetic strategies for tailoring structural and electronic properties through phase control, morphology engineering, metal atom embedding and heteroatom doping etc. The structure-activity relationships in the selective cleavage of C-C/C-O bond with diverse active sites and emerging applications of molybdenum nitrides as catalytic supports are also proposed. This review critically analyzes the unique performance of molybdenum nitrides in biomass conversion for producing bio-fuel and chemicals. Key research frontiers such as active site characterization, catalyst reconstruction mechanisms, regeneration protocols, in situ spectroscopy, and machine learning-assisted design etc. are also proposed to promote the future design and development of multi-metallic molybdenum nitride. The systematic insights provided aim to guide future development of multi-metallic molybdenum nitride catalysts for sustainable biorefining.