Progress in Single/Multi Atoms and 2D-Nanomaterials for Electro/Photocatalytic Nitrogen Reduction: Experimental, Computational and Machine Leaning Developments

The conversion of atmospheric nitrogen (N₂) into ammonia (NH₃), known as nitrogen fixation, plays a crucial role in sustaining life on Earth, facing innovation with electrocatalytic and photocatalytic methods. These approaches promise gentler conversions from atmospheric nitrogen to ammonia, diverging from the energy-intensive Haber-Bosch process, which requires complex plant infrastructure. Vitality lies in eco-friendly, cost-effective, and energy-efficient pathways. The challenge is that electrocatalysts and photocatalysts for nitrogen reduction have shown low Faraday efficiency, hampered by hydrogen evolution. This work delves into recent strides in electro/photo-catalytic nitrogen fixation/reduction, deciphering mechanisms, catalysts, and prospects. By unveiling the core principles steering these processes, it dissects efficiency drivers. Experimental and theoretical studies, ranging from density functional calculations/simulations to machine learning-based catalyst screening, mark the path toward highly efficient catalysts, including single/multi-atom catalysts embedded in 2D materials. The journey explores diverse catalysts, assessing their performance, spotlighting emerging nanomaterials, heterostructures, and co-catalyst techniques. Perspectives on future directions and potential applications of electro/photo-catalytic nitrogen fixation/reduction are offered, by emphasizing their role in sustainable nitrogen management and their implications for global agriculture and environmental sustainability.