Metal Nitrides

Abstract

Transition metal nitrides are characterized by high melting points, hardness, and resistance to corrosion. These physical properties are desired for catalytic materials that require resistance against attrition and sintering under reaction conditions. Since high specific area materials became available with clean surfaces, they have attracted considerable attention as catalysts for many reactions including hydrotreating (hydrodesulfurization, hydrodenitrogenation, and hydrodeoxygenation) hydrogenation, dehydrogenation, and ammonia synthesis. Metal nitrides demonstrate catalytic advantages over their parent metals in activity, selectivity, and resistance to poisoning. They have been found to be good catalysts for a number of reactions typically catalyzed by noble metals of high cost and limited supply. Structure, bonding, synthesis, and surface reactivity of transition metal carbides are discussed.