Transition Metal Nitrides: Multifunctional Catalysts and Energy Materials with Tailorable Architectures

Transition metal nitrides (TMNs) exhibit notable multifunctionality due to their superior physicochemical and catalytic attributes. This review delineates their crystal architectures, thermodynamic robustness, and inherent merits such as enhanced catalytic activity, sintering resistance, and operational selectivity. Density functional theory analyses have illuminated their electronic, optical, vibrational, plasmonic, mechanical, and morphological characteristics. TMNs, including mono-, bi-, and tri-metallic variants, are synthesized via routes like ammonolysis, chemical vapor deposition, electrodeposition, and pyrolysis. Their structural dimensionality (0D–3D) significantly influences performance, with structural engineering enhancing their functional characteristics. Applications span photocatalysis (hydrogen evolution reaction, oxygen evolution reaction, overall water splitting, hydrogen peroxide production (H₂O₂), carbon dioxide reduction (CO₂RR), and pollutant degradation), electrocatalysis, energy storage (batteries, supercapacitors), and photovoltaics, emphasizing TMNs technological relevance.